Patent Publication Number: US-2012028705-A1

Title: Game machine, performance control method, and performance control program

Description:
BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The present invention relates to a game machine, a performance control method, and a performance control program. 
     2. Description of the Prior Art 
     With the recent improvement of computer performance, there have been disclosed a lot of technologies for creating a three-dimensional virtual space just like a real space by using computer graphics. 
     Technologies to display a performance image on such a display screen of game machines typified by a pachinco machine have also been disclosed. The performance image is obtained by mapping a three-dimensional object arranged in a three-dimensional virtual space from the point of view of a virtual camera placed in a predetermined position in the virtual space. 
     For example, Japanese Patent Application Laid-Open No. 2006-099636 discloses a technology for updating and displaying a video picture (image) from the point of view of the virtual camera in real time when the point of view of the virtual camera or the position of the three-dimensional object is moved. 
     Here, the position of the three-dimensional object arranged in the three-dimensional virtual space is expressed by a three-dimensional coordinate system. 
     When the virtual camera (point of view) moves in the three-dimensional virtual space, the distance between the virtual camera and the three-dimensional object is calculated on the basis of the three-dimensional coordinate system. 
     As mentioned above, the distance between the three-dimensional object arranged in the three-dimensional virtual space and the virtual camera is calculated by using the coordinates in the three dimensional space after the identification of the coordinate position of the three-dimensional object arranged in the three-dimensional virtual space. It is therefore not easily possible to calculate the distance between the three-dimensional object and the virtual camera, or to identify the point of view (direction) of the virtual camera. 
     SUMMARY OF THE INVENTION 
     It is thus an object of the present invention to provide a game machine, a performance control method, and a performance control program that make it possible by simple processing to identify the distance between a three-dimensional object and a virtual camera and the point of view of the virtual camera, and make it possible to provide a highly amusing game by means of the player&#39;s operations on the virtual camera. 
     To achieve the foregoing object, the invention according to claim  1  includes: map information storing means for storing map information that is constituted by at least one section; layer information storing means for storing layer information that has a plurality of layers set for the section of the map information stored in the map information storing means, a performance object being placed in at least one of the layers in the at least one section, the performance object specifying a performance mode in a game using a game medium; layer change operation accepting means for accepting a layer change operation for changing a layer of the section to be displayed on a display device among the layers that are set for the section by the layer information stored in the layer information storing means; and performance means for providing a performance in the performance mode specified by the performance object when the layer is changed to where the performance object is placed, by the layer change operation accepted by the layer change operation accepting means. 
     The invention according to claim  2  is the invention according to claim  1 , further including section change operation accepting means for accepting a section change operation for changing the section to be displayed on the display device among the sections constituting the map information, and wherein the performance means provides a performance in the performance mode specified by the performance object when the section is changed to the section that has the layer where the performance object is placed, by the section change operation accepted by the section change operation accepting means, and the layer is changed to where the performance object is placed, by the layer change operation. 
     The invention according to claim  3  is the invention according to claim  1  or  2 , including: distance measuring means for measuring a distance between the section before the section change operation of the section change operation accepting means and the section that has the layer where the performance object is placed; and layer change operation enabling means for enabling the layer change operation of the layer change operation accepting means if two sections are decided to be the same from the distance measured by the distance measuring means. 
     The invention according to claim  4  is the invention according to any one of claims  1  to  3 , further including: deciding means for deciding a result of drawing whether or not to perform a jackpot game in the game; and section change control means for disabling the changing of the section to the section that has the layer where the performance object is placed, by the section change operation accepted by the section change operation accepting means if the decision means decide that the result of drawing is not to perform the jackpot game, and enabling the changing of the section to the other section if the result of drawing is to perform the jackpot game, and wherein the performance means provides a performance in the performance mode specified by the performance object if the changing of the section to the other section is enabled by the section change control means, a display range is changed to the other section, and the layer is changed to where the performance object is placed among the layers set for the other section. 
     The invention according to claim  5  includes: as map information storing means, storing map information that is constituted by at least one section; as layer information storing means, storing layer information that has a plurality of layers set for the section of the map information stored in the map information storing means, a performance object being placed in at least one of the layers in the at least one section, the performance object specifying a performance mode in a game using a game medium; as layer change operation accepting means, accepting a layer change operation for changing a layer of the section to be displayed on a display device among the layers that are set for the section by the layer information stored in the layer information storing means; and as performance means, providing a performance in the performance mode specified by the performance object when the layer is changed to where the performance object is placed, by the layer change operation accepted by the layer change operation accepting means. 
     The invention according to claim  6  causes a computer to function as: map information storing means for storing map information that is constituted by at least one section; layer information storing means for storing layer information that has a plurality of layers set for the section of the map information stored in the map information storing means, a performance object being placed in at least one of the layers in the at least one section, the performance object specifying a performance mode in a game using a game medium; layer change operation accepting means for accepting a layer change operation for changing a layer of the section to be displayed on a display device among the layers that are set for the section by the layer information stored in the layer information storing means; and performance means for providing a performance in the performance mode specified by the performance object when the layer is changed to where the performance object is placed, by the layer change operation accepted by the layer change operation accepting means. 
     According to the present invention, there are provided the effects that it is possible by simple processing to identify the distance between a three-dimensional object and the virtual camera and the point of view of the virtual camera, and it is possible to provide a highly amusing game by means of the player&#39;s operations on the virtual camera. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a front view of a game machine which is configured through the application of the game machine, the performance control method, and the performance control program according to an embodiment of the present invention; 
         FIG. 2  is a perspective view of the game machine which is configured through the application of the game machine, the performance control method, and the performance control program according to the embodiment of the present invention, where a glass frame arranged on the front side is opened; 
         FIG. 3  is a perspective view of the back side of the game machine which is configured through the application of the game machine, the performance control method, and the performance control program according to the embodiment of the present invention; 
         FIG. 4  is a block diagram showing the detailed configuration of the entire game machine which is configured through the application of the game machine, the performance control method, and the performance control program according to the embodiment of the present invention; 
         FIG. 5  is a block diagram showing the detailed configuration of an image control board which constitutes the block diagram of the entire game machine shown in  FIG. 4 ; 
         FIG. 6  is a block diagram showing the detailed configuration of a performance control unit which is configured through the application of the game machine, the performance control method, and the performance control program according to the embodiment of the present invention; 
         FIG. 7  is a diagram showing an example of two-dimensional map information; 
         FIG. 8  is a diagram showing a control panel including a performance button and arrow keys; 
         FIG. 9  is a flowchart showing the detailed procedure of main processing to be performed by a main control board which constitutes the block diagram of the entire game machine shown in  FIG. 4 ; 
         FIG. 10  is a flowchart showing the detailed procedure of timer interrupt processing to be performed by the main control board which constitutes the block diagram of the entire game machine shown in  FIG. 4 ; 
         FIG. 11  is a flowchart showing the detailed procedure of special symbol special electric control processing to be performed by the main control board which constitutes the block diagram of the entire game machine shown in  FIG. 4 ; 
         FIG. 12  is a flowchart showing the detailed procedure of special symbol storing and judgment processing to be performed by the main control board which constitutes the block diagram of the entire game machine shown in  FIG. 4 ; 
         FIG. 13  is a flowchart showing the detailed procedure of main processing to be performed by a performance control board which constitutes the block diagram of the entire game machine shown in  FIG. 4 ; 
         FIG. 14  is a flowchart showing the detailed procedure of timer interrupt processing to be performed by the performance control board which constitutes the block diagram of the entire game machine shown in  FIG. 4 ; 
         FIG. 15  is a flowchart showing the detailed procedure of command analysis processing to be performed by the performance control board which constitutes the block diagram of the entire game machine shown in  FIG. 4 ; 
         FIG. 16  is a flowchart showing the detailed procedure continued from that of the command analysis processing to be performed by the performance control board shown in  FIG. 15 ; 
         FIG. 17  is a flowchart showing the detailed procedure of main processing to be performed by the image control board; 
         FIG. 18  is a flowchart showing the detailed procedure of performance control processing to be performed by the performance control unit of the game machine which is configured through the application of the game machine, the performance control method, and the performance control program according to the embodiment of the present invention; 
         FIG. 19  is a flowchart showing the detailed procedure of setting processing which appears in  FIG. 18 ; 
         FIG. 20  is a flowchart showing the detailed procedure of the setting processing which appears in  FIG. 18 ; 
         FIG. 21  is a diagram showing an example of two-dimensional map information; 
         FIG. 22  is a diagram showing an example of two-dimensional map information; 
         FIG. 23  is a diagram showing an example of two-dimensional map information; 
         FIG. 24  is a diagram showing layer information which is set for each section; 
         FIG. 25  is a diagram showing a control panel including a performance button and a joystick; and 
         FIG. 26  is a diagram showing a state where reservation images are displayed on the display device of the game machine according to the embodiment of the present invention. 
     
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
     Hereinafter, an embodiment of the game machine, the performance control method, and the performance control program according to the present invention will be described in detail with reference to the accompanying drawings. 
     Embodiment 
       FIG. 1  is an example of an apparatus configuration diagram showing a game machine that is configured through the application of the game machine, the performance control method, and the performance control program according to the embodiment of the present invention.  FIG. 2  is a perspective view of the game machine  1  according to the present invention where a glass frame is opened.  FIG. 3  is a perspective view of the back side of the game machine  1 . 
     The game machine  1  includes an outer frame  60  which is attached to island facilities in a game parlor, and a glass frame  50  which is rotatably supported by the outer frame  60  (see  FIGS. 1 and 2 ). The outer frame  60  is equipped with a game panel  2  which has a game field  6  for game balls to cascade down. The glass frame  50  is provided with: an operating handle  3  which is rotationally operated to shoot game balls toward the game field  6 ; sound output devices  32  which are composed of speakers; performance illumination devices  34  which include a plurality of lamps; and a performance button  35  which is intended to change a performance mode by a depressing operation. 
     As shown in  FIG. 8 , up, down, right, and left arrow keys  35 - 1  may be arranged around the performance button  35 . As shown in FIG.  25 , joystick  37  may be arranged next to the performance button, the joystick is an operation lever. There need to be provided at least either the arrow keys  35 - 1  or the joystick  37 . 
     The glass frame  50  also has a tray  40  for storing a plurality of game balls. The tray  40  is inclined downward so that game balls flow down toward the operating handle  3  (see  FIG. 2 ). An inlet port for accepting game balls is formed at the end of inclination of the tray  40 . Game balls taken into the inlet port are driven by a ball feed solenoid  4   b  and sent to a ball feed opening  41  formed in the back side of the glass frame  50  one by one. 
     The game ball sent to the ball feed opening  41  is guided through a shoot rail  42 , which is inclined toward a flipper member  4 c, to the end of inclination of the shoot rail  42 . A stopper  43  for stopping and retaining a game ball is arranged above the end of inclination of the shoot rail  42 . A single game ball sent from the ball feed opening  41  is stopped and retained at the end of inclination of the shoot rail  42  (see  FIG. 2 ). 
     When the player rotates the operating handle  3 , a shoot volume  3   b  directly connected to the operating handle  3  is also rotated. The shoot volume  3   b  adjusts the shooting strength of the game ball, and the flipper member  4   c  which is directly connected to a shooting solenoid  4   a  is rotated by the adjusted shooting strength. When the flipper member  4   c  is rotated, the flipper member  4   c  shoots off the game ball stored at the end of inclination of the shoot rail  42 , and the game ball is shot into the game field  6 . 
     The game ball shot from the shoot rail  42  as described above ascends between rails  5   a  and  5   b , passes a backflow prevention piece  5   c  to reach the game field  6 , and then cascades down within the game field  6 . Here, the game ball falls in an unpredictable manner because of a plurality of pins and pinwheels arranged on the game field  6 . 
     A plurality of general prize holes  12  are formed in the game field  6 . The general prize holes  12  are provided with respective general prize hole detection switches  12   a . When the general prize hole detection switches  12   a  detect the entry of a game ball, predetermined winning balls (for example, ten game balls) are dispensed. 
     A first start hole  14 , a second start hole  15 , and a second bonus prize hole  17  are formed in the lower central area of the game field  6 . The first start hole  14  and the second start hole  15  constitute start areas which game balls can enter. The second bonus prize hole  17  also allows the entry of game balls. 
     The second start hole  15  has a pair of movable pieces  15   b . The second start hole  15  is motion-controlled between a first mode where the pair of movable pieces  15   b  are maintained in a closed state and a second mode where the pair of movable pieces  15   b  are in an open state. When the second start hole  15  is controlled to the first mode, the winning members of the second bonus prize hole  17  arranged directly above the second start hole  15  function as an obstacle to the acceptance of game balls. 
     On the other hand, when the second start hole  15  is controlled to the second mode, the pair of movable pieces  15   b  function as a tray, facilitating the entry of game balls into the second start hole  15 . That is, if the second start hole  15  is in the first mode, there is no chance for game balls to enter. If the second start hole  15  is in the second mode, there is a higher chance for game balls to enter. 
     Here, the first start hole  14  is provided with a first start hole detection switch  14   a  which detects the entry of a game ball. The second start hole  15  is provided with a second start hole detection switch  15   a  which detects the entry of a game ball. When the first start hole detection switch  14   a  or the second start hole detection switch  15   a  detects the entry of a game ball, a special symbol judgment random number value and the like are acquired to perform drawing for the right to play a jackpot game to be described later (hereinafter, referred to as “jackpot drawing”). 
     Predetermined winning balls (for example, three game balls) are also dispensed when the first start hole detection switch  14   a  or the second start hole detection switch  15   a  detects the entry of a game ball. 
     The second bonus prize hole  17  includes an opening formed in the game panel  2 . The second bonus prize hole  17  has on its lower part a second bonus prize hole opening and closing door  17   b  which can be protruded from the game panel side toward a glass plate  52 . The second bonus prize hole opening and closing door  17   b  is motion-controlled between an open state of being protruded from the game panel side and a closed state of sinking into the game panel side. 
     When protruded from the game panel side, the second bonus prize hole opening and closing door  17   b  functions as a tray that guides game balls into the second bonus prize hole  17 , so that game balls can enter the second bonus prize hole  17 . The second bonus prize hole  17  is provided with a second bonus prize hole detection switch  17   a . When the second bonus prize hole detection switch  17   a  detects the entry of a game ball, predetermined winning balls (for example,  15  game balls) are dispensed. 
     A normal symbol gate  13  which constitutes a normal area where game balls can pass and a first bonus prize hole  16  which game balls can enter are formed in the right area of the game field  6 . 
     Such a configuration prevents game balls from passing or entering the normal symbol gate  13  or the first bonus prize hole  16  unless the operating handle  3  is largely rotated to launch the game balls by strong force. 
     In particular, with such a configuration, game balls cascading down the left area of the game field  6  will not pass the normal symbol gate  13  even in a Jitan (quick) game state to be described later. Since the pair of movable pieces  15   b  on the second start hole  15  will not enter the open state, it is difficult for game balls to enter the second start hole  15 . 
     The normal symbol gate  13  is provided with a gate detection switch  13   a  which detects the passage of a game ball. When the gate detection switch  13   a  detects the passage of a game ball, a normal symbol judgment random number value is acquired to perform “normal symbol drawing” to be described later. 
     The first bonus prize hole  16  is usually maintained in the closed state by a first bonus prize hole opening and closing door  16   b , thereby precluding the entry of game balls. When a special game to be described later is started, the first bonus prize hole opening and closing door  16   b  is opened. The first bonus prize hole opening and closing door  16   b  functions as a tray that guides game balls into the first bonus prize hole  16 , so that game balls can enter the first bonus prize hole  16 . The first bonus prize hole  16  is provided with a first bonus prize hole detection switch  16   a . When the first bonus prize hole detection switch  16   a  detects the entry of a game ball, predetermined winning balls (for example, 15 game balls) are dispensed. 
     An out hole  11  is formed in the bottom area of the game field  6 . The out hole  11  is intended to drain game balls that fail to enter any of the general prize holes  12 , the first start hole  14 , the second start hole  15 , the first bonus prize hole  16 , and the second bonus prize hole  17 . 
     A decoration member  7  which has an influence on the cascading of game balls is provided in the center of the game field  6 . A liquid crystal display (LCD)  31  is arranged generally in the center area of the decoration member  7 . A belt-shaped performance drive device  33  is arranged above the liquid crystal display  31 . 
     The liquid crystal display  31  displays images on standby when no game is being played, and displays images according to the progress of a game. In particular, the liquid crystal display  31  displays three performance symbols  36  for notifying the result of jackpot drawing to be described later. A certain combination of performance symbols  36  (such as  777 ) remains to be displayed to notify of hitting a jackpot as the result of jackpot drawing. 
     More specifically, when a game ball enters the first start hole  14  or the second start hole  15 , each of the three performance symbols  36  is scrolled each. After a lapse of predetermined time, each of them stopped scrolling to display the performance symbols  36 . While the display of the performance symbols  36  is changing, a variety of images, characters, and the like are displayed in order to give the player a sense of high anticipation of hitting a jackpot. 
     The performance drive device  33  is intended to give the player a sense of anticipation by means of its operating mode. For example, the performance drive device  33  makes an operation such that the belt moves downward, or a rotating member rotates in the belt center. Such modes of operation of the performance drive device  33  are intended to give the player various feelings of anticipation. 
     In addition to the various types of performance devices described above, the sound output devices  32  enables audio performance by outputting the characters&#39; voice, background music (BGM), sound effects (SE), and the like. The performance illumination devices  34  change the direction of light projection and the color of each lamp for illumination-based performances. 
     The performance button  35 , the arrow keys  35 - 1 , and/or the joystick  37  are enabled, for example, only when a message to operate the performance button  35 , the arrow keys  35 - 1 , and/or the joystick  37  appears on the liquid crystal display  31 . The performance button  35  is provided with a performance button detection switch  35   a . The arrow keys are provided with not-shown arrow key detection switches. The joystick  37  is provided with a joystick detection switch  35   b . When such detection switches detect the player&#39;s operation, an additional performance is executed according to the operation. 
     A first special symbol display device  20 , a second special symbol display device  21 , a normal symbol display device  22 , a first special symbol reservation indicator  23 , a second special symbol reservation indicator  24 , and a normal symbol reservation indicator  25  are arranged on the lower right of the game field  6 . 
     The first special symbol display device  20  is intended to notify of the result of jackpot drawing that is performed when a game ball enters the first start hole  14 . The first special symbol display device  20  is composed of a 7-segment LED. More specifically, there are provided a plurality of special symbols corresponding to results of jackpot drawing. The first special symbol display device  20  displays a special symbol corresponding to a result of jackpot drawing, thereby notifying the player of the result of drawing. For example, “7” appears when a jackpot is hit, and “−” appears when not. Such “7” and “−” displayed are the special symbols. The special symbols are not immediately displayed, but are stopped and displayed after showing variations for a predetermined time. 
     Here, the “jackpot drawing” refers to the processing of acquiring a special symbol judgment random number value and judging whether the special symbol judgment random number value acquired is the one corresponding to a “jackpot” or the one corresponding to a “small jackpot” when a game ball enters the first start hole  14  or the second start hole  15 . The result of jackpot drawing is not immediately notified to the player. The first special symbol display device  20  displays the special symbol with variations such as blinking, and after a lapse of a predetermined variation time, the special symbol corresponding to the result of jackpot drawing is displayed without variations to notify the player of the result of drawing. 
     The second special symbol display device  21  is intended to notify of the result of jackpot drawing that is performed when a game ball enters the second start hole  15 . The display mode is the same as that of the special symbols on the first special symbol display device  20 . 
     In the present embodiment, the “jackpot” refers to winning the right to play a jackpot game in the jackpot drawing that is performed when a game ball enters the first start hole  14  or the second start hole  15 . In the “jackpot game,” a total of 15 round games are played where the first bonus prize hole  16  or the second bonus prize hole  17  is opened up. The maximum open time of the first bonus prize hole  16  or the second bonus prize hole  17  in each round game is set to a predetermined time. A single round game ends if a predetermined number of game balls (for example, nine) enter the first bonus prize hole  16  or the second bonus prize hole  17  during that period. 
     That is, in the “jackpot game,” game balls enter the first bonus prize hole  16  or the second bonus prize hole  17  and the player can win balls according to the entering balls. 
     The normal symbol display device  22  is intended to notify the result of normal symbol drawing which is performed when a game ball passes the normal symbol gate  13 . As will be detailed later, the normal symbol display device  22  is lit when hitting a win in the normal symbol drawing. The second start hole  15  is then controlled to the second mode for a predetermined time. 
     Here, the “normal symbol drawing” refers to the processing of acquiring a normal symbol judgment random number value and determining whether the normal symbol judgment random number value acquired is one corresponding to “winning” when a game ball passes the normal symbol gate  13 . Again, the result of normal symbol drawing is not notified immediately after a game ball passes the normal symbol gate  13 . The normal symbol display device  22  displays the normal symbol with variations such as blinking, and after a lapse of a predetermined variation time, the normal symbol corresponding to the result of normal symbol drawing is displayed without variations to notify the player of the result of drawing. 
     The right for jackpot drawing is reserved under a certain condition when a game ball entering the first start hole  14  or the second start hole  15  unable to perform jackpot drawing immediately, such as during a special symbol is being displayed with variations and when during a special game as described later. 
     More specifically, the special symbol judgment random number value that is acquired when a game ball enters the first start hole  14  is stored as a first reservation. The special symbol judgment random number value that is acquired when a game ball enters the second start hole  15  is stored as a second reservation. 
     The maximum number of each reservation is set to four. The numbers of reservations are displayed on the first special symbol reservation indicator  23  and the second special symbol reservation indicator  24 , respectively. 
     If there is one first reservation, the left LED of the first special symbol reservation indicator  23  is lit. If there are two first reservations, the two LEDs of the first special symbol reservation indicator  23  are lit. If there are three first reservations, the left LED of the first special symbol reservation indicator  23  is blinked and the right LED is lit. If there are four first reservations, the two LEDs of the first special symbol reservation indicator  23  are blinked. 
     The second special symbol reservation indicator  24  displays the number of second reservations as mentioned in the first special symbol reservation. 
     The maximum number of normal symbol reservations is also set to four. The number of reservations is displayed on the normal symbol reservation indicator  25  in the same way as with the first special symbol reservation indicator  23  and the second special symbol reservation indicator  24 . 
     The glass frame  50  supports the glass plate  52  in front (player side) of the game panel  2 . The game field  6  is visibly covered with the glass plate  52 . The glass plate  52  is detachably fixed to the glass frame  50 . 
     The glass frame  50  is coupled to the outer frame  60  via hinge mechanism parts  51  on either one of the lateral sides (for example, the left side when the game machine  1  is viewed from the front). The glass frame  50  is configured so that the other lateral side (for example, the right side when the game machine  1  is viewed from the front) can be rotated about the hinge mechanism parts  51  in an opening direction from the outer frame  60 . The glass frame  50  covers the game panel  2  along with the glass plate  52 , and can be rotated about the hinge mechanism parts  51  in a door-like manner, thereby the interior of the outer frame  60  including the game panel  2  can be exposed. 
     The other end of the glass frame  50  is provided with a lock mechanism which fixes the other end of the glass frame  50  to the outer frame  60 . The fixing of the lock mechanism can be released by a dedicated key. The glass frame  50  is provided with a door open switch  133  which detects whether the glass frame  50  is opened from the outer frame  60 . 
     As shown in  FIG. 3 , a main control board  110 , a performance control board  120 , a dispensing control board  130 , a power supply board  170 , a game information output terminal strip  30 , and the like are arranged on the back side of the game machine  1 . The power supply board  170  has a power plug  171  for supplying power to the game machine  1 , and a not-shown power supply switch. 
     Next, control means for controlling the game progress will be described with reference to a block diagram of the entire game machine  1  of  FIG. 4 . 
     The main control board  110  is main control means for controlling basic operations of the game. The main control board  110  drives the first special symbol display device  20 , a first bonus prize hole opening and closing solenoid  16   c , and the like for game control, when various types of detection signals are input from the first start hole detection switch  14   a  and the like. 
     The main control board  110  includes at least a one-chip microcomputer  110   m  which is composed of a main CPU  110   a , a main ROM  110   b , and a main RAM  110   c , and input ports and output ports (not shown) for main control. 
     The input ports for main control are connected to: the dispensing control board  130 ; the general prize hole detection switches  12   a  which detect the entry of a game ball into the general prize holes  12 ; the gate detection switch  13   a  which detects the entry of a game ball into the normal symbol gate  13 ; the first start hole detection switch  14   a  which detects the entry of a game ball into the first start hole  14 ; the second start hole detection switch  15   a  which detects the entry of a game ball into the second start hole  15 ; the first bonus prize hole detection switch  16   a  which detects the entry of a game ball into the first bonus prize hole  16 ; and the second bonus prize hole detection switch  17   a  which detects the entry of a game ball into the second bonus prize hole  17 . Various signals are input to the main control board  110  through the input ports for main control. 
     The output ports for main control are connected to: the dispensing control board  130 ; a start hole opening and closing solenoid  15   c  which operates to open and close the pair of movable pieces  15   b  on the second start hole  15 ; the first bonus prize hole opening and closing solenoid  16   c  which operates the first bonus prize hole opening and closing door  16   b ; a second bonus prize hole opening and closing solenoid  17   c  which operates the second bonus prize hole opening and closing door  17   b ; the first special symbol display device  20  and the second special symbol display device  21  which display special symbols; the normal symbol display device  22  which displays a normal symbol; the first special symbol reservation indicator  23  and the second special symbol reservation indicator  24  which indicate the numbers of balls reserved for special symbols; the normal symbol reservation indicator  25  which indicates the number of balls reserved for normal symbols; and the game information output terminal strip  30  which outputs external information signals. Various signals are output through the output ports for main control. 
     The main CPU  110   a  reads a program stored in the main ROM  110   b  and performs arithmetic processing on the basis of the input signals from the detection switches and timers. The main CPU  110   a  also controls the devices and indicators directly, and transmits commands to other boards depending on the result of arithmetic processing. 
     The main CPU  110   a  can perform jackpot drawing for a reserved ball prior to the drawing processing corresponding to the reserved ball, thereby pre-acquiring (pre-reading) the result of drawing beforehand. Here, the main CPU  110   a  transmits the pre-acquired result of drawing to the image control board  150  through the performance control board  120 . 
     The main ROM  110   b  of the main control board  110  stores programs for game control, and data and tables necessary for making various game determinations. For example, the main ROM  110   b  stores: a jackpot judgment table referenced for jackpot drawing; a winning judgment table referenced for normal symbol drawing; a symbol determination table to determine the special symbols to remain to be displayed; a jackpot game end time setting data table for determining the game state after the end of a jackpot; a special electrical gadget start mode determination table to determine the opening and closing conditions of the bonus prize hole opening and closing doors; a bonus prize hole open mode table; a variation pattern determination table to determine the variation pattern of the special symbols; and so on. 
     The tables mentioned above are just a few examples of characteristic tables among the tables according to the present embodiments. A lot of other not-shown tables and programs are provided for game progresses. 
     The main RAM  110   c  of the main control board  110  functions as a data work area in the arithmetic processing of the main CPU  110   a , and includes a plurality of storing areas. 
     For example, the main RAM  110   c  has a normal symbol reserved number (G) storing area, a normal symbol reservation storing area, a normal symbol data storing area, a first special symbol reserved number (U 1 ) storing area, a second special symbol reserved number (U 2 ) storing area, a first special symbol random number value storing area, a second special symbol random number value storing area, a round game number (R) storing area, an open number (K) storing area, a bonus prize hole entering ball number (C) storing area, a game state storing area (a high probability game flag storing area and a quick game flag storing area), a high probability game number (X) counter, a quick number (J) counter, a game state buffer, a stop symbol data storing area, a performance transmission data storage area, a special symbol time counter, a special game timer counter, and various other timer counters. The storing areas mentioned above are just a few examples, and there are provided a lot of other storing areas are provided. 
     The game information output terminal strip  30  is a substrate for outputting the external information signals generated by the main control board  110  to a hall computer or the like of the game parlor. The game information output terminal strip  30  is wired and connected to the main control board  110 , and has connectors for connecting to the hall computer or the like in the game parlor, which transmits and receives external information. 
     The power supply board  170  includes a capacitor-based backup power supply, and supplies a power supply voltage to the game machine  1 . The power supply board  170  monitors the power supply voltage supplied to the game machine  1 , and if the power supply voltage falls to or below a predetermined value and below, outputs an electricity disconnection detection signal to the main control board  110 . More specifically, the electricity disconnection detection signal of high level activates the main CPU  110   a . The electricity disconnection detection signal of low level deactivates the main CPU  110   a . The backup power supply is not limited to the capacitor. For example, a battery may be used. Both of the capacitor and the battery may be used. 
     The performance control board  120  mainly controls performances during a game, on standby, and the like. The performance control board  120  includes a sub CPU  120   a , a sub ROM  120   b , and a sub RAM  120   c . The performance control board  120  is connected with the main control board  110  to allow one-way communication from the main control board  110  to the performance control board  120 . The sub CPU  120   a  reads a program stored in the sub ROM  120   b  and performs arithmetic processing on the basis of a command transmitted from the main control board  110 , or an input signal from the performance button detection switch  35   a , the arrow key detection switches, the joystick detection switch  35   b , or a timer. On the basis of the processing, the sub CPU  120   a  transmits corresponding data to the lamp control board  140  or the image control board  150 . The sub RAM  120   c  functions as a data work area in the arithmetic processing of the sub CPU  120   a.    
     For example, the sub CPU  120   a  of the performance control board  120  receives a variation pattern specification command which specifies the mode of variation of the special symbols from the main control board  110 . Then, the sub CPU  120   a  analyzes the content of the variation pattern specification command received, and generates data allowing the liquid crystal display  31 , the sound output devices  32 , the performance drive device  33 , and the performance illumination devices  34  to execute predetermined performances. The sub CPU  120   a  transmits the above-mentioned data to the image control board  150  and the lamp control board  140 . 
     The sub ROM  120   b  of the performance control board  120  stores programs for performance control, and data and tables necessary for making various game determinations. 
     For example, the sub ROM  120   b  stores a performance pattern determination table for determining a performance pattern on the basis of the variation pattern specification command received from the main control board, a performance symbol determination table for determining the combination of performance images  36  to remain to be displayed, and the like. 
     The tables mentioned above are just a few examples of characteristic tables among the tables according to the present embodiment. A lot of other not-shown tables and programs are provided for game progress. 
     The sub RAM  120   c  of the performance control board  120  functions as a data work area in the arithmetic processing of the sub CPU  120   a , and includes a plurality of storing areas. 
     The sub RAM  120   c  has a game state storing area, a performance mode storing area, a performance pattern storing area, a performance symbol storing area, and the like. The storing areas mentioned above are just a few examples, and there are provided a lot of other storing areas are provided. 
     The dispensing control board  130  performs a dispensing control on game balls. The dispensing control board  130  includes a one-chip microcomputer that is composed of a not-shown dispensing CPU, dispensing ROM, and dispensing RAM. The dispensing control board  130  is connected to the main control board  110  so as to be capable of two-way communications. The dispensing CPU reads a program stored in the dispensing ROM and performs arithmetic processing on the basis of input signals from a dispensed ball count detection switch  132  which detects whether game balls are dispensed, the door open switch  133 , and timers. On the basis of the processing, the dispensing CPU transmits corresponding data to the main control board  110 . 
     A dispensing motor  131  of a dispensing device for dispensing a predetermined number of game balls from the game ball reservoir is connected to the output side of the dispensing control board  130 . On the basis of a dispensing number specification command transmitted from the main control board  110 , the dispensing CPU reads a predetermined program from the dispensing ROM, performs arithmetic processing, and controls the dispensing motor  131  of the dispensing device to dispense predetermined game balls. 
     Here, the dispensing RAM functions as a data work area in the arithmetic processing of the dispensing CPU. 
     The lamp control board  140  performs a lighting control on the performance illumination devices  34  arranged on the game panel  2 , and performs a drive control on motors for changing the directions of light projection. The lamp control board  140  also performs an energization control on drive sources such as solenoids and motors that actuate the performance drive device  33 . The lamp control board  140  is connected to the performance control board  120 , and performs the foregoing controls on the basis of various commands transmitted from the performance control board  120 . 
     The image control board  150  is connected to the liquid crystal display  31  and the sound output devices  32 . On the basis of various commands transmitted from the performance control board  120 , the image control board  150  controls an image display on the liquid crystal display  31  and a sound output on the sound output devices  32 . 
     The image control board  150  will be detailed below with reference to a block diagram of the image control board of  FIG. 5 . 
     The image display control will now be described with reference to the block diagram of the image control board  150  of  FIG. 5 . 
     The image control board  150  includes a host CPU  150   a , a host RAM  150   b , a host ROM  150   c , a CG ROM  151 , a quartz oscillator  152 , a VRAM  153 , and a VDP (Video Display Processor)  2000  which are intended for the image display control on the liquid crystal display  31 , and a sound control circuit  3000 . 
     The host CPU  150   a  instructs the VDP  2000  to display image data stored in the CG ROM  151  on the liquid crystal display  31  on the basis of a performance pattern specification command received from the performance control board  120 . Such an instruction is given by setting data into control registers of the VDP  2000  and outputting a display list including a group of drawing control commands. 
     On receiving a V blank interrupt signal or a drawing end signal from the VDP  2000 , the host CPU  150   a  performs interrupt processing if necessary. 
     On the basis of the performance pattern specification command received from the performance control board  120 , the host CPU  150   a  also instructs the sound control circuit  3000  to make the sound output devices  32  output predetermined sound data. 
     The host RAM  150   b  that is built in the host CPU  150   a  functions as a data work area in the arithmetic processing of the host CPU  150   a , and temporarily stores data that is read from the host ROM  150   c.    
     The host ROM  150   c  that is made of a mask ROM stores programs for the control processing of the host CPU  150   a , a display list generation program for generating a display list, an animation pattern for displaying an animated performance pattern, animation information, and so on. 
     The animation pattern is referenced when displaying the animated performance pattern. The animation pattern stores a combination of pieces of animation scene information to be included in the performance pattern, the order of display of the pieces of animation scene information, and the like. The animation scene information stores such information as wait frame (display time), target data (sprite ID number, transmission source address, and the like), parameters (sprite display position, transmission destination address, and the like), and the method of drawing. 
     The CG ROM  151  that is constituted by a flash memory, EEPROM, EPROM, mask ROM, or the like. The CG ROM  151  stores compressed image data (sprite, movie) and so on which includes pixel information on a predetermined area of pixels (for example, 32×32 pixels). The pixel information is composed of color number information that specifies a color number for each pixel, and an a value that indicates the transparency of the image. 
     The CG ROM  151  also stores space information on a three-dimensional virtual space using a three-dimensional coordinate system, and object information (object shape, color, and the like) on three-dimensional objects to be arranged in the three-dimensional virtual space. 
     The CG ROM  151  further stores uncompressed palette data which associates color number information for specifying color numbers with display color information for actual color display. 
     The CG ROM  151  may store partly compressed but not entirely compressed image data. Various known compression methods such as MPEG-4 may be used for the movie compression. 
     The quartz oscillator  152  outputs a pulsed signal to the VDP  2000 . The frequency-divided pulsed signal allows to generate a system clock for the VDP  2000  for controlling and synchronizing signals intended for synchronization with the liquid crystal display  31 , and the like. 
     The VRAM  153  is made of an SRAM which is capable of writing and reading image data at high speed. 
     The VRAM  153  includes: a display list storing area  153   a  which temporarily stores a display list that is output from the host CPU  150   a ; a decompression storing area  153   b  which stores image data that is decompressed by a decompression circuit; and a first frame buffer  153   c  and a second frame buffer  153   d  which are intended to draw or display an image. The VRAM  153  also stores the palette data. 
     The two frame buffers are switched alternately between a “drawing frame buffer” and a “display frame buffer” each time on starting to draw. 
     The VDP  2000  is a so-called image processor. The VDP  2000  reads image data from either one of the frame buffers (display frame buffer) on the basis of an instruction from the host CPU  150   a , and generates a video signal (such as RGB signal) and outputs the same to the liquid crystal display on the basis of the read image data. 
     The VDP  2000  includes a performance control unit  200  as well as not-shown control registers, a CG bus I/F, a CPU I/F, a clock generation circuit, a decomposition circuit, a drawing circuit, a display circuit, and a memory controller, which are connected by a bus. The procedure of the processing to be performed by the performance control unit  200  is shown in  FIGS. 18 and 19 , which will be described later. 
     The control registers are registers allowing the VDP  2000  to control drawing and display. The drawing control and display control are performed by writing and reading data to/from the control registers. The host CPU  150   a  can write and read data to/from the control registers through the CPU I/F. 
     The control registers are composed of six types of registers, including: a system control register for making basic settings necessary for the operation of the VDP  2000 ; a data transfer register for making a setting necessary for data transfer; a drawing register for making a setting for drawing control; a bus interface register for making a setting necessary for bus access; a decompression register for making a setting necessary for the decompression of a compressed image; and a display register for making a setting for display control. 
     The CG bus I/F is an interface circuit for communication with the CG ROM  151 . The image data from the CG ROM  151  is input to the VDP  2000  through the CG bus I/F. 
     The CPU I/F is an interface circuit for communication with the host CPU  150   a . The host CPU  150   a  outputs a display list to the VDP  2000 , accesses the control registers, and receives various interrupt signals from the VDP  2000  through the CPU I/F. 
     The data transfer circuit performs data transfer between various types of devices. 
     Specifically, the data transfer circuit performs data transfer between the host CUP  150   a  and the VRAM  153 , data transfer between the CG ROM  151  and the VRAM  153 , and mutual data transfer between various storing areas of the VRAM  153  (including the frame buffers). 
     The clock generation circuit inputs the pulsed signal from the quartz oscillator  152 , and generates the system clock which determines the arithmetic processing speed of the VDP  2000 . The clock generation circuit also generates a synchronizing signal generating clock, and outputs synchronizing signals to the liquid crystal display  31  through the display circuit. 
     The decompression circuit is a circuit for decompressing the compressed image data in the CG ROM  151 . The decompression circuit stores the decompressed image data into the expansion storing area  153   b.    
     The drawing circuit is a circuit for performing a sequence control based on a display list which is composed of a group of drawing control commands. 
     The display circuit is a circuit that generates a video signal, or an RGB signal (analog signal) which shows color data on the image, from the image data (digital signal) stored in the “display frame buffer” of the VRAM  153 . The display circuit outputs the generated video signal (RGB signal) to the liquid crystal display  31 . The display circuit also outputs the synchronizing signals intended for synchronization with the liquid crystal display  31  (such as a vertical synchronizing signal and a horizontal synchronizing signal) to the liquid crystal display  31 . 
     In the present embodiment, the analog RGB signal converted from the digital signal is output to the liquid crystal display  31  as the video signal. However, the digital signal itself may be output as the video signal. 
     The memory controller controls to switch between the “drawing frame buffer” and the “display frame buffer” when an instruction for frame buffer switching is given from the host CPU  150   a.    
     The sound control circuit  3000  includes a sound ROM which stores a lot of sound data. The sound control circuit reads a predetermined program on the basis of a command transmitted from the performance control board  120 , and performs sound output of the sound output devices  32 . 
       FIG. 6  is a block diagram showing the detailed configuration of the performance control unit which is configured through the application of the game machine, the performance control method, and the performance control program according to the embodiment of the present invention. 
     In  FIG. 6 , the performance control unit  200  constitutes part of the VDP  2000  of the image control board  150  shown in  FIG. 5 . The performance control unit  200  includes a receiving unit  201 , a condition decision unit  202 , a condition storing unit  203 , a performance processing control unit  204 , an information read unit  205 , a map information storing unit  206 , a performance information storing unit  207 , a section setting unit  208 , a layer setting unit  209 , a distance calculation unit  210 , an operation accepting unit  211 , a position information association unit  212 , and a display control unit  213 . 
     The host CPU  150   a  of the image control board  150  receives data (performance pattern specification command) for providing a predetermined performance from the performance control board  120  which controls performances during a game, on standby, and the like. The host CPU  150   a  issues an instruction to the VDP  2000  to display image data stored in the CG ROM  151  on the liquid crystal display  31 . The instruction is received by the receiving unit  201  of the performance control unit  200 . 
     The receiving unit  201  transmits data based on the instruction to the condition decision unit  202 . 
     The condition decision unit  202  decides whether the data transmitted from the receiving unit  201  is a display request for a performance that uses a performance image mapped by arranging three-dimensional objects in a three-dimensional virtual space and imaging the three-dimensional objects with a virtual camera. 
     The three-dimensional virtual space is also called “three-dimensional virtual environment.” In the environment, virtual reality information on “length,” “breadth,” and “height” is spatially rendered so that objects are presented to the player as if in the real space. The information on “length” and “breadth” will also be referred to as information on “width” and “depth.” 
     Three-dimensional objects are arranged in the three-dimensional virtual space to reproduce a virtual reality space. 
     The player can operate the virtual camera by using the performance button  35  and the arrow keys  35 - 1  which are arranged along with the performance button  35  as shown in  FIG. 8 . The player can also operate the virtual camera in the three-dimensional virtual space by using the joystick  37  such as shown in  FIG. 25  instead of the arrow keys  35 - 1  shown in  FIG. 8 . 
     Here, the virtual camera defines the point of view when displaying the three-dimensional objects arranged in the three-dimensional virtual space as a performance image on the liquid crystal display  31 . The player operates the virtual camera which is the point of view of a character. The character is expressed as a three-dimensional object when applied to the three-dimensional virtual space. Hereinafter, such an object will be referred to as a “character object.” 
     If the condition decision unit  202  decides that the data is a display request for a performance image that is mapped by imaging three-dimensional objects arranged in the three-dimensional virtual space with the virtual camera, the condition decision unit  202  issues a request for performance processing to the performance processing control unit  204 . The condition decision unit  202  also instructs the information read unit  205  to read information, and instructs the section setting unit  208  to set the section where to place the item object. 
     The performance processing control unit  204  initially acquires performance information based on the processing-requested performance from the performance information storing unit  207 , and performs performance processing based on the performance information. 
     In the performance processing, the performance processing control unit  204  decides the performance contents, and transmits information for generating a performance image based on the decided performance contents to the display control unit  213  as a display instruction. 
     Based on the display instruction, the display control unit  213  reads the object information in the three-dimensional virtual space stored in the CG ROM  151 , and arranges three-dimensional objects in the three-dimensional virtual space in a three-dimensional world coordinate system. The display control unit  213  also performs a display control on the performance image which is obtained by imaging the three-dimensional objects arranged in the three-dimensional virtual space, followed by mapping. 
     Accepting an operation on the virtual camera, or the point of view of the character object, from the operation accepting unit  211 , the display control unit  213  draws (renders) the performance image imaged and mapped by the virtual camera and displays the performance image on the liquid crystal display  31 . 
     The drawing processing initially performs processing to determine the point of view which is defined by the virtual camera. The processing is intended to determine the range of sight from the camera. After the determination of the point of view, the display position on the display screen is determined when drawing the display image from the determined point of view. 
     Directional information on the camera, the degrees of magnification (zoom values), and the aspect ratio of the display screen are determined as the display position. In the three-dimensional virtual space, the zoom values to be set include a zoom value in the horizontal direction (horizontal zoom value) and a zoom value in the vertical direction (vertical zoom value). The horizontal zoom value can be expressed as a zoom value on the “X-Y plane,” and the horizontal zoom value as a zoom value on the “X-Z plane.” 
     After the determination of the display position on the display screen, objects to be seen are determined. That is, objects that are out of sight (not visible) from the point of view of the camera are excluded. 
     Parameter information for forming a display image to be displayed on the display screen is thus determined. Then, the coordinates of the apexes of geometric figures (also referred to as “primitives”) or components that constitute the visible objects, such as polygons, are transformed from the coordinate systems of the object spaces of the respective objects into the coordinate system of a world space. 
     Subsequently, the coordinates of the objects transformed into the coordinate system of the world space are transformed into the coordinate system of a camera space that is in sight from the point of view of the camera. The camera space is a virtual space that depends on the camera which defines the point of view (the point of origin in the coordinate space) of the scene to be narrated by the display image. 
     Here, processing may be performed to increase or decrease the apex coordinates of the primitives (polygons) of the objects in the coordinate system of the camera space. Such processing can be performed by software such as a “geometry shader.” 
     Culling processing is performed to delete geometric figures that are no longer needed in the camera space as a result of the coordinate transformation into the coordinate system of the camera space, from among the polygons or other primitives that constitute the three-dimensional objects. Clipping processing is also performed to clip only three-dimensional objects to be displayed on the display screen. That is, the areas other than clipped by the clipping processing will not be displayed. 
     The culling processing and clipping processing are not absolutely necessary, and are performed for the sake of reducing the load of rendering processing. 
     Subsequently, the apexes of the geometric figures (primitives) or components that constitute the three-dimensional objects are projected to map the spatial coordinates in the camera space onto two-dimensional screen space coordinates. This generates coordinates in a two-dimensional space. As mentioned above, the mapping processing may be performed before the culling processing and clipping processing. 
     After the transformation of the three-dimensional objects into the screen space coordinates in the two-dimensional space, the coordinates are subjected to rasterization processing. The rasterization processing associates the polygons constituting the three-dimensional objects with pixels on the display screen so that the polygons can be displayed on the display screen as display images. 
     Shading processing (light source setting processing) is then performed to shade the rasterized display images. It is possible to perform alpha blending of multiplying the display images by a values to superpose a plurality of semitransparent images and Z-buffer processing of drawing only near side objects by using a depth information storing area (Z-buffer) may also be performed if necessary. 
     Through such processing, the display images are rendered. 
     The display images rendered are displayed on the display screen of the display device, whereby the image from the point of view of the camera is displayed. 
     In this way, the rendering processing by the display control unit  213  is performed each time the player makes an input operation on the performance button, arrow keys, and the like. That is, the rendering processing is performed for display each time a three-dimensional object moves. 
     When imaging the three-dimensional virtual space with the virtual camera, position information on the virtual camera (character object) is managed by using two-dimensional information. Processing is also performed to grasp the point of view of the virtual camera. 
     The processing is started when the condition decision unit  202  instructs the information read unit  205  to read information and the section setting unit  208  to set the section to place the item object. When instructed by the condition decision unit  202  to read information, the information read unit  205  reads “two-dimensional map information”stored in the map information storing unit  206 . The information read unit  205  also reads information on the location of the virtual camera (character object), stored in the performance information storing unit  207 . 
     The information read by the information read unit  205  is transmitted to the section setting unit  208 . 
     The two-dimensional map information describes a vertical and horizontal two-dimensional plane of the three-dimensional virtual space as divided into a plurality of sections (also referred to as “blocks”), and defines the range of movement of the character object. The two-dimensional map information is also referred to as a “2D map.” Examples of such information are shown in  FIGS. 7 ,  21 ,  22 , and  23 . 
     When the section setting unit  208  is instructed by the condition decision unit  202  to set the section to place the item object and information is transmitted from the information read unit  205 , the section setting unit  208  sets any one of the sections constituting the two-dimensional map information as the section to place the item object. Here, the section setting unit  208  sets a section that is based on the performance information transmitted from the information read unit  205 , to be the section to place the item object. 
     For example, (1) suppose that a reach performance is being given in a drawing state (reach state) of making drawing whether or not to enter a jackpot game state, with all performance symbols but one in a predetermined combination according to variations of the performance symbols in a normal game state. If the result of drawing is specified in the performance information, the section setting unit  208  sets a predetermined section based on the result of drawing to be the section to place the item object. 
     If the result of drawing hits a “jackpot” and the game state shifts to the jackpot game state, the section setting unit  208  allocates the section to place the item object to any one of the sections to which the virtual camera (character object) can move during the reach performance.  FIG. 7  shows an example of the two-dimensional map information which is configured by dividing the vertical and horizontal two-dimensional plane of the three-dimensional virtual space into a plurality of sections (also referred to as “blocks”). 
       FIG. 7  shows the section to which the virtual camera (character object) belongs, the section in which the item object is placed, and the positional relationship between the sections. The performance button  35  and the arrow keys  35 - 1  such as shown in  FIG. 8  or the joystick  37  such as shown in  FIG. 25  can be operated to move the virtual camera (character object) in the three-dimensional space. The virtual camera (character object) can be moved to sections corresponding to the vertical and horizontal two-dimensional plane of the three-dimensional virtual space, i.e., any of eight sections that adjoin vertically, horizontally, or diagonally. 
     In the example shown in  FIG. 7 , the section to which the virtual camera (character object) belongs and the section in which the item object is placed are in a positional relationship such that the item object is placed two sections to the right and three sections vertically away from the section where the virtual camera (character object) is located. 
     Assuming that a move as much as one section in any of the vertical, horizontal, and diagonal directions can be made for each variation, the item object can be reached in a minimum of three moves. 
     The item object will be relocated to a section closer to where the virtual camera belongs as the reach performance time elapses. When the remaining time of the reach performance falls below a predetermined time (such as 5 sec), the item object is relocated to the same section as where the virtual camera belongs. 
     On the other hand, if the result of drawing is not a “jackpot,” the item object is placed in a section to which the virtual camera (character object) cannot move during the reach performance. Again, assume that a move as much as one section in any of the vertical, horizontal, and diagonal directions can be made for each variation. In the example of  FIG. 7 , the item object is then placed in a not-shown section that is like ten sections to the right and ten sections vertically away from where the virtual camera (character object) is located. 
     (2) Suppose that a game ball has entered a start hole and performance symbols are under variation when another game ball enters the start hole and the variations of the performance symbols based on the entry are reserved (reserved state). If the pre-read result of pre-read processing to acquire (pre-acquire) the result of drawing for the reserved variations in advance is specified in the performance information, the section setting unit  208  sets a predetermined section based on the pre-read result as the section to place the item object. 
     Suppose the pre-read result is such that four reservation images which indicate the state of reservation are lit on the display screen of the display device such as shown in  FIG. 26  and the result of drawing for the variations of the fourth reservation hits a “jackpot”so that the game state enters the jackpot game state. In such a case, the section setting unit  208  sets any one of sections to which the virtual camera can be moved within five variations including the current one (current variation), to be the section to place the item object. 
     If the pre-read result shows that none of the results of drawing for the reserved variations hits a “jackpot,” the section setting unit  208  sets any one of sections to which the virtual camera cannot be moved as the section to place the item object. 
     After the section to place the item object is set by the section setting unit  208 , the layer setting unit  209  sets a layer to place the item object. 
     The sections constituting the two-dimensional map information have a plurality of layers each. In each section, the point of view of the virtual camera (character object) can be changed and operated upward or downward to change the direction of the virtual camera to any one of the layers. 
       FIG. 24  shows an example of the layers in each section. The layer information shown in  FIG. 24  includes three layers, or a first layer, a second layer, and a third layer. 
     By initial setting, the point of view of the virtual camera is directed to the intermediate second layer (second point of view). When changed upward, the point of view of the virtual camera is directed to the third layer (third point of view). When changed downward, the point of view of the virtual camera is directed to the first layer (first point of view). 
     After the item object is placed in any one of the layers in any one of the sections constituting the two-dimensional map information, the distance calculation unit  210  calculates the distance from the section to which the virtual camera (character object) currently belongs (block-to-block distance), and the distance from the layer to which the point of view is currently directed (layer distance). 
     When the operation accepting unit  211  accepts a camera operation on the virtual camera, the position information association unit  212  performs mapping processing to identify the section of the two-dimensional map information corresponding to the position of the virtual camera in the three-dimensional virtual space on the basis of the position moved by the camera operation, the position being expressed by three-dimensional coordinates in the three-dimensional virtual space. The display control unit  210  calculates the distance between that section and the section where the item object is placed. 
     The distance calculation unit  210  transmits the information on the calculated distance to the performance processing control unit  204 . The performance processing control unit  204  provides a performance on the basis of the distance information transmitted. 
     The mapping processing is intended to identify the section of the two-dimensional map information that corresponds to a set of three-dimensional coordinates in the three-dimensional virtual space. Specifically, the section of the two-dimensional map information is identified on the basis of the horizontal and vertical coordinates on the X-Y plane in the three-dimensional coordinates. 
     If the block-to-block distance calculated is “0,” i.e., [vertical 0, horizontal 0] and the distance between the layer of the point of view of the virtual camera and the layer where the item object is placed is “0,” the distance calculation unit  210  notifies the performance processing control unit  204  of it. Consequently, the performance processing control unit  204  provides a performance for the situation when the character object (virtual camera) wins the item object. For example, the performance processing control unit  204  provides a progressive jackpot performance. 
     Next, the progress of a game with the game machine  1  will be described with reference to flowcharts. 
     Referring to  FIG. 9 , the main processing of the main control board  110  will be described. 
     When power is supplied from the power supply board  170 , a system reset occurs in the main CPU  110   a . The main CPU  110   a  performs the following main processing. 
     Initially, at step S 10 , the main CPU  110   a  performs initialization processing. In the processing, the main CPU  110   a  loads a startup program from the main ROM  110   b  in response to the power-on, and performs processing to initialize flags and the like stored in the main RAM  110   c.    
     At step S 20 , the main CPU  110   a  performs performance random number value update processing to update a reach judgment random number value and a special symbol variation random number value which are intended to determine the variation mode (variation time) of special symbols. 
     At step S 30 , the main CPU  110   a  updates a special symbol judgment initial random number value, a jackpot symbol initial random number value, a small jackpot symbol initial random number value, and a normal symbol judgment initial random number value. Subsequently, the main CPU  110   a  repeats the processing of steps S 20  and S 30  until predetermined interrupt processing is performed. 
     Referring to  FIG. 10 , timer interrupt processing of the main control board  110  will be described. 
     A resetting clock pulse generation circuit provided on the main control board  110  generates a clock pulse at predetermined intervals (4 ms), which initiates the following timer interrupt processing. 
     Initially, at step S 100 , the main CPU  110   a  saves the information stored in the registers of the main CPU  110   a  into a stack area. 
     At step S 110 , the main CPU  110   a  performs time control processing to update various types of timer counters. The time control processing includes the processing of updating the special symbol time counter, the processing of updating the special game timer counter which pertains to the open time of special electrical gadgets and the like, the processing of updating a normal symbol time counter, and the processing of updating a normal electric open time counter. Specifically, the main CPU  110   a  performs processing to subtract  1  from each of the special symbol time counter, the special game timer counter, the normal symbol time counter, and the normal electric open time counter. 
     At step S 120 , the main CPU  110   a  performs random number update processing on the special symbol judgment random number value, the jackpot symbol random number value, the small jackpot symbol random number value, and the normal symbol judgment random number value. 
     Specifically, the main CPU  110   a  adds 1 to the random number values and random number counters for update. If an added random number counter exceeds the maximum value of its random number range (when the random number counter goes around), the main CPU  110   a  resets the random number counter to 0 and updates the random number values anew from the respective initial random number values at that time. 
     At step S 130 , the main CPU  110   a  performs initial random number value update processing to update the special symbol judgment initial random number value, the jackpot symbol initial random number value, the small jackpot symbol initial random number value, and the normal symbol judgment initial random number value as in step S 30 . 
     At step S 200 , the main CPU  110   a  performs input control processing. 
     In the processing, the main CPU  110   a  performs input processing to determine whether there is an input to each of the general prize hole detection switch  12   a , the first bonus prize hole detection switch  16   a , the second bonus prize hole detection switch  17   a , the first start hole detection switch  14   a , the second start hole detection switch  15   a , and the gate detection switch  13   a.    
     Specifically, when various detection signals are input from the general prize hole detection switch  12   a , the first bonus prize hole detection switch  16   a , the second bonus prize hole detection switch  17   a , the first start hole detection switch  14   a , and the second start hole detection switch  15   a , the main CPU  110   a  adds predetermined data to each of winning ball counters for update. The winning ball counters are arranged for the each prize holes and used for winning balls. 
     If the detection signal from the first start hole detection switch  14   a  is input and the data set in the first special symbol reserved number (U 1 ) storing area is smaller than  4 , the main CPU  110   a  adds 1 to the first special symbol reserved number (U 1 ) storing area. The main CPU  110   a  then acquires the special symbol judgment random number value, the jackpot symbol random number value, the small jackpot symbol random number value, the reach judgment random number value, and the special symbol variation random number value, and stores the acquired various random number values into a predetermined storing section (zeroth storing section to fourth storing section) in the first special symbol random number value storing area. 
     Similarly, if the detection signal from the second start hole detection switch  15   a  is input and the data set in the second special symbol reserved number (U 2 ) storing area is smaller than 4, the main CPU  110   a  adds 1 to the second special symbol reserved number (U 2 ) storing area. The main CPU  110   a  then acquires the special symbol judgment random number value, the jackpot symbol random number value, the small jackpot symbol random number value, the reach judgment random number value, and the special symbol variation random number value, and stores the acquired various random number values into a predetermined storing section (zeroth storing section to fourth storing section) in the second special symbol random number value storing area. 
     If the detection signal from the gate detection switch  13   a  is input and the data set in the normal symbol reserved number (G) storing area is smaller than 4, the main CPU  110   a  adds 1 to the normal symbol reserved number (G) storing area. The main CPU  110   a  then acquires the normal symbol judgment random number value, and stores the acquired normal symbol judgment random number value into a predetermined storing section (zeroth storing section to fourth storing section) in the normal symbol reservation storing area. 
     If the detection signal from the first bonus prize hole detection switch  16   a  or the second bonus prize hole detection switch  17   a  is input, the main CPU  110   a  adds 1 to the bonus prize hole entering ball number (C) storing area for update. The bonus prize hole entering ball number (c) storing area is intended to count game balls entering the first bonus prize hole  16  or the second bonus prize hole  17 . 
     At step S 300 , the main CPU  110   a  performs special symbol special electric control processing for performing jackpot drawing and controlling the special electrical gadget and the game state. 
     At step S 400 , the main CPU  110   a  performs normal symbol normal electric control processing for performing normal symbol drawing and controlling the normal electrical gadgets. 
     Specifically, the main CPU  110   a  initially determines if value of one or higher is set in the normal symbol reserved number (G) storing area. The main CPU  110   a  ends the normal symbol normal electric control processing this time unless value of one or higher is set in the normal symbol reserved number (G) storing area. 
     If value of one or higher is set in the normal symbol reserved number (G) storing area, the main CPU  110   a  subtracts  1  from the value stored in the normal symbol reserved number (G) storing area. The main CPU  110   a  then shifts the normal symbol judgment random number values stored in the first to fourth storing sections of the normal symbol reservation storing area to the respective preceding storing sections. This shift results in overwriting and erasing the normal symbol judgment random number value that is previously written in the zeroth storing section. 
     The main CPU  110   a  then performs processing to determine whether the normal symbol judgment random number value stored in the zeroth storing section of the normal symbol reservation storing area corresponds to a “win.” Subsequently, the normal symbol display device  22  displays normal symbols with variations and after a lapse of the normal symbol variation time displays without variations the normal symbol that corresponds to the result of normal symbol drawing. If the normal symbol judgment random number value referenced hits a “win,” the start hole opening and closing solenoid  15   c  is driven to control the second start hole  15  to the second mode for a predetermined open time. 
     When in a non-quick game state, the normal symbol variation time is set to 29 sec. If “win,” the second start hole  15  is controlled to the second mode for 0.2 sec. On the other hand, when in the quick game state, the normal symbol variation time is set to 0.2 sec. If “win, ” the second start hole  15  is controlled to the second mode for 3.5 sec. 
     At step S 500 , the main CPU  110   a  performs dispensing control processing. 
     In the dispensing control processing, the main CPU  110   a  refers to the respective winning ball counters to generate dispensing number specification commands corresponding to the respective prize holes, and transmits the generated dispensing number specification commands to the dispensing control board  130 . 
     At step S 600 , the main CPU  110   a  performs processing to generate external information data, start hole opening and closing solenoid data, first bonus prize hole opening and closing solenoid data, second bonus prize hole opening and closing solenoid data, special symbol display device data, normal symbol display device data, and data on a stored number specification command. 
     At step S 700 , the main CPU  110   a  performs output control processing. In the processing, the main CPU  110   a  performs port output processing to output the signals of the external information data, the start hole opening and closing solenoid data, the first bonus prize hole opening and closing solenoid data, and the second bonus prize hole opening and closing solenoid data which are created in the foregoing step S 600 . 
     In order to light the LEDs of the first special symbol display device  20 , the second special symbol display device  21 , and the normal symbol display device  22 , the main CPU  110   a  performs display device output processing to output the special symbol display device data and the normal symbol display device data which are created in the foregoing step S 600 . 
     The main CPU  110   a  also performs command transmission processing to transmit commands set in the performance transmission data storage area of the main RAM  110   c  to the performance control board  120 . 
     At step S 800 , the main CPU  110   a  restores the information saved in step S 100  into the registers of the main CPU  110   a.    
     Referring to  FIG. 11 , the special symbol special electric control processing of the main control board  110  will be described. 
     Initially, at step S 301 , the main CPU  110   a  loads the value of special symbol special electric processing data. At step S 302 , the main CPU  110   a  refers to a branch address included in the special symbol special electric processing data loaded. If the special symbol special electric processing data=0, the main CPU  110   a  shifts the processing to special symbol storing and judgment processing (step S 310 ). If the special symbol special electric processing data=1, the main CPU  110   a  shifts the processing to special symbol variation processing (step S 320 ). If the special symbol special electric processing data=2, the main CPU  110   a  shifts the processing to special symbol stop processing (step S 330 ). If the special symbol special electric processing data=3, the main CPU  110   a  shifts the processing to jackpot game processing (step S 340 ). If the special symbol special electric processing data=4, the main CPU  110   a  shifts the processing to jackpot game end processing (step S 350 ). If the special symbol special electric processing data=5, the main CPU  110   a  shifts the processing to small jackpot game end processing (step S 360 ). 
     The “special symbol special electric processing data” is set in each subroutine of the special symbol special electric control processing when necessary, so that subroutines necessary for a game are processed appropriately. 
     In the special symbol storing and judgment processing of step S 310 , the main CPU  110   a  performs such processing as jackpot judgment processing, special symbol determination processing for determining a special symbol to remain to be displayed, and variation time determination processing for determining the special symbol variation time. Referring to  FIG. 12 , the special symbol storing and judgment processing will now be described in the concrete. 
       FIG. 12  is a flowchart showing the special symbol storing and judgment processing of the main control board  110 . 
     Initially, at step S 311 , the main CPU  110   a  judges whether data of 1 or higher is set in the first special symbol reserved number (U 1 ) storing area or the second special symbol reserved number (U 2 ) storing area. 
     If data of 1 or higher is set in neither of the first special symbol reserved number (U 1 ) storing area or the second special symbol reserved number (U 2 ) storing area, the main CPU  110   a  ends the special symbol storing and judgment processing this time while maintaining the special symbol special electric processing data=0. 
     On the other hand, if data of 1 or higher is set in the first special symbol reserved number (U 1 ) storing area or the second special symbol reserved number (U 2 ) storing area, the main CPU  110   a  shifts the processing to step S 312 . 
     At step S 312 , the main CPU  110   a  performs the jackpot judgment processing. 
     Specifically, if data of 1 or higher is set in the second special symbol reserved number (U 2 ) storing area, the main CPU  110   a  subtracts 1 from the value stored in the second special symbol reserved number (U 2 ) storing area. The main CPU  110   a  then shifts the various random number values stored in the first to fourth storing sections of the second special symbol random number value storing area to the respective preceding storing sections. This overwrites and erases the various random number values that are previously written in the zeroth storing section. The main CPU  110   a  then judges whether the special symbol judgment random number value stored in the zeroth storing section of the second special symbol random number value storing area corresponds to a “jackpot,” or whether the random number value corresponds to a “small jackpot.” 
     If data of 1 or higher is not set in the second special symbol reserved number (U 2 ) storing area and data of 1 or higher is set in the first special symbol reserved number (U 1 ) storing area, the main CPU  110   a  subtracts  1  from the value stored in the first special symbol reserved number (U 1 ) storing area. The main CPU  110   a  then shifts the various random number values stored in the first to fourth storing sections of the first special symbol random number value storing area to the respective preceding storing sections. Again, this overwrites and erases the various random number values that are previously written in the zeroth storing section. The main CPU  110   a  then judges whether the special symbol judgment random number value stored in the zeroth storing section of the first special symbol random number value storing area corresponds to a “jackpot,” or whether the random number value corresponds to a “small jackpot.” 
     In the present embodiment, the random number values stored in the second special symbol random number value storing area are shifted (consumed) with priority over those stored in the first special symbol random number value storing area. 
     However, this is not restrictive. The first special symbol random number value storing area and the second special symbol random number value storing area may be shifted in order of entry into the start holes. The first special symbol random number value storing area may be shifted with priority over the second special symbol random number value storing area. 
     At step S 313 , the main CPU  110   a  performs the special symbol determination processing for determining the type of the special symbol to remain to be displayed. 
     In the special symbol determination processing, the main CPU  110   a  determines a jackpot symbol on the basis of the jackpot symbol random number value stored in the zeroth storing section of the first special symbol random number value storing area if the foregoing jackpot judgment processing (step S 312 ) results in a “jackpot.” If the foregoing jackpot judgment processing (step S 312 ) results in a “small jackpot,” the main CPU  110   a  determines a small jackpot symbol on the basis of the small jackpot symbol random number value stored in the zeroth storing section of the first special symbol random number value storing area. If the foregoing jackpot judgment processing (step S 312 ) results in a “miss,” the main CPU  110   a  determines a miss symbol. 
     The main CPU  110   a  then stores stop symbol data corresponding to the determined special symbol into the stop symbol data storing area. 
     At step S 314 , the main CPU  110   a  performs the variation time determination processing for the special symbol. 
     Specifically, the main CPU  110   a  determines the variation pattern of special symbols on the basis of the reach judgment random number value and the special symbol variation random number value stored in the zeroth storing section of the first special symbol random number value storing area. Subsequently, the main CPU  110   a  determines the special symbol variation time corresponding to the variation pattern of special symbols determined. The main CPU  110   a  then performs processing to set the special symbol time counter to a counter value corresponding to the special symbol variation time determined. 
     At step S 315 , the main CPU  110   a  sets variation display data for making the first special symbol display device  20  or the second special symbol display device  21  display special symbols with variations (LED blinking), into a predetermined processing area. With the variation display data set in the predetermined processing area, data for turning on/off the LEDs is appropriately created in the foregoing step S 600 . The created data is output at step S 700 , whereby the first special symbol display device  20  or the second special symbol display device  21  makes a display with variations. 
     When starting to display special symbols with variations, the main CPU  110   a  sets a special symbol variable pattern specification command (first special symbol variation pattern specification command or second special symbol variation pattern specification command) that corresponds to the variation pattern of special symbols determined in the foregoing step S 314 , into the performance transmission data storage area of the main RAM  110   c.    
     At step S 316 , the main CPU  110   a  changes “the special symbol special electric processing data=0” to “the special symbol special electric processing data=1,” thereby preparing for a shift into the subroutine for the special symbol variation processing. The main CPU  110   a  then ends the special symbol storing and judgment processing. 
     Referring to  FIG. 13 , the main processing of the performance control board  120  will be described. 
     At step S 1000 , the sub CPU  120   a  performs initialization processing. In the processing, the sub CPU  120   a  loads a main processing program from the sub ROM  120   b  in response to the power-on, and performs processing to initialize and set flags and the like stored in the sub RAM  120   c . After the end of the processing, the sub CPU  120   a  shifts the processing to step S 1400 . 
     At step S 1100 , the sub CPU  120   a  performs performance random number update processing. In the processing, the sub CPU  120   a  performs processing to update random numbers (such as performance random number value 1, performance random number value 2, performance symbol determination random number value, and performance mode determination random number value) stored in the sub RAM  120   c . Subsequently, the sub CPU  120   a  repeats the processing of the step S 1100  described above until predetermined interrupt processing is performed. 
     Referring to  FIG. 14 , timer interrupt processing of the performance control board  120  will be described. 
     A not-shown resetting clock pulse generation circuit provided on the performance control board  120  generates a clock pulse at predetermined intervals (2 ms). A timer interrupt processing program is loaded, and the timer interrupt processing of the performance control board is performed. 
     Initially, at step S 1400 , the sub CPU  120   a  saves the information stored in the registers of the sub CPU  120   a  to a stack area. 
     At step S 1500 , the sub CPU  120   a  performs processing to update various timer counters that are used in the performance control board  120 . 
     At step S 1600 , the sub CPU  120   a  performs command analysis processing. In the processing, the sub CPU  120   a  performs processing to analyze a command that is stored in a reception buffer of the sub RAM  120   c . The command analysis processing will be detailed later with reference to  FIGS. 15 and 16 . When the performance control board  120  receives a command transmitted from the main control board  110 , not-shown command reception interrupt processing occurs in the performance control board  120 , whereby the received command is stored into the reception buffer. Subsequently, the processing of analyzing the received command is performed in this step S 1600 . 
     At step S 1700 , the sub CPU  120   a  checks for the signal of the performance button detection switch  35   a , and performs performance input control processing on the performance button  35 . 
     At step S 1800 , the sub CPU  120   a  performs data output processing to transmit various types of commands set in a transmission buffer of the sub RAM  120   c  to the lamp control board  140  and the image control board  150 . 
     At step S 1900 , the sub CPU  120   a  restores the information saved in step S 1400  to the registers of the sub CPU  120   a.    
     Referring to  FIGS. 15 and 16 , the command analysis processing of the performance control board  120  will be described. It should be appreciated that the command analysis processing  2  of  FIG. 16  is performed in succession to the command analysis processing  1  of  FIG. 15 . 
     At step S 1601 , the sub CPU  120   a  checks for the presence or absence of a command in the reception buffer, thereby checking for command reception. 
     If there is no command in the reception buffer, the sub CPU  120   a  ends the command analysis processing. If there is a command in the reception buffer, the sub CPU  120   a  shifts the processing to step S 1610 . 
     At step S 1610 , the sub CPU  120   a  checks whether the command stored in the reception buffer is a demo specification command. 
     If the command stored in the reception buffer is a demo specification command, the sub CPU  120   a  shifts the processing to step S 1611 . If not a demo specification command, the sub CPU  120   a  shifts the processing to step S 1620 . 
     At step S 1611 , the sub CPU  120   a  performs demo performance pattern determination processing to determine a demo performance pattern. 
     Specifically, the sub CPU  120   a  determines the demo performance pattern, and sets the determined demo performance pattern into the performance pattern storing area. To transmit the information on the determined demo performance pattern to the image control board  150  and the lamp control board  140 , the sub CPU  120   a  further sets a performance pattern specification command based on the determined demo performance pattern into the transmission buffer of the sub RAM  120   c.    
     At step S 1620 , the sub CPU  120   a  checks whether the command stored in the reception buffer is a special symbol storing specification command. 
     If the command stored in the reception buffer is a special symbol storing specification command, the sub CPU  120   a  shifts the processing to step S 1621 . If not a special symbol storing specification command, the sub CPU  120   a  shifts the processing to step S 1630 . 
     At step S 1621 , the sub CPU  120   a  performs special symbol stored number determination processing. In the processing, the sub CPU  120   a  analyzes the special symbol storing specification command to determine the number of special symbol reservation images for the liquid crystal display  31  to display, and transmits a special symbol display number specification command corresponding to the determined number of special symbol reservation images to display to the image control board  150  and the lamp control board  140 . 
     At step S 1630 , the sub CPU  120   a  checks whether the command stored in the reception buffer is a performance symbol specification command. 
     If the command stored in the reception buffer is a performance symbol specification command, the sub CPU  120   a  shifts the processing to step S 1631 . If not a performance symbol specification command, the sub CPU  120   a  shifts the processing to step S 1640 . 
     At step S 1631 , the sub CPU  120   a  performs performance symbol determination processing to determine the performance symbol  36  to be stopped and displayed on the liquid crystal display  31  on the basis of the content of the performance symbol specification command received. 
     Specifically, the sub CPU  120   a  analyzes the performance symbol specification command to determine performance symbol data that constitutes a combination of performance symbols  36  depending on the presence or absence of a jackpot and the type of the jackpot. The sub CPU  120   a  sets the determined performance symbol data into the performance symbol storing area. To transmit the performance symbol data to the image control board  150  and the lamp control board  140 , the sub CPU  120   a  also sets a stop symbol specification command that indicates the performance symbol data into the transmission buffer of the sub RAM  120   c.    
     At step S 1632 , the sub CPU  120   a  performs performance mode determination processing. In the processing, the sub CPU  120   a  acquires a random number value from the performance mode determination random number values updated in the foregoing step S 1100 , and determines a performance mode from among a plurality of performance modes (such as normal performance mode and chance performance mode) on the basis of the performance mode determination random number value acquired and the performance symbol specification command received. The determined performance mode is set into the performance mode storing area. 
     At step S 1640 , the sub CPU  120   a  checks whether the command stored in the reception buffer is a variation pattern specification command. 
     If the command stored in the reception buffer is a variation pattern specification command, the sub CPU  120   a  shifts the processing to step S 1641 . If not a variation pattern specification command, the sub CPU  120   a  shifts the processing to step S 1650 . 
     At step S 1641 , the sub CPU  120   a  performs variation performance pattern determination processing. In the processing, the sub CPU  120   a  acquires a random number value from the performance random number values 1 updated in the foregoing step S 1100 , and determines a variation performance pattern from among a plurality of variation performance patterns on the basis of the performance random number value 1 acquired, the variation pattern specification command received, and the performance mode set in the performance mode storing area. 
     Subsequently, the liquid crystal display  31 , the sound output devices  32 , the performance drive device  33 , and the performance illumination devices  34  are controlled on the basis of the performance pattern. It should be noted that the variation mode of the performance symbols  36  is determined on the basis of the variation performance pattern determined here. 
     At step S 1650 , the sub CPU  120   a  checks whether the command stored in the reception buffer is a symbol fix command. 
     If the command stored in the reception buffer is a symbol fix command, the sub CPU  120   a  shifts the processing to step S 1651 . If not a symbol fix command, the sub CPU  120   a  shifts the processing to step S 1660 . 
     At step S 1651 , the sub CPU  120   a  performs performance symbol stop display processing. In the processing, the sub CPU  120   a  sets a stop specification command for displaying without variations a performance symbol into the transmission buffer of the sub RAM  120   c  in order to stop and display a performance symbol  36 . 
     At step S 1660 , the sub CPU  120   a  judges whether the command stored in the reception buffer is a game state specification command. 
     If the command stored in the reception buffer is a game state specification command, the sub CPU  120   a  shifts the processing to step S 1661 . If not a game state specification command, the sub CPU  120   a  shifts the processing to step S 1670 . 
     At step S 1661 , the sub CPU  120   a  sets data that indicates the game state based on the received game state specification command, into the game state storing area of the sub RAM  120   c.    
     At step S 1670 , the sub CPU  120   a  checks whether the command stored in the reception buffer is an opening command. 
     If the command stored in the reception buffer is an opening command, the sub CPU  120   a  shifts the processing to step S 1671 . If not an opening command, the sub CPU  120   a  shifts the processing to step S 1680 . 
     At step S 1671 , the sub CPU  120   a  performs winning start performance pattern determination processing to determine a winning start performance pattern. 
     Specifically, the sub CPU  120   a  determines the winning start performance pattern on the basis of the opening command, and sets the determined winning start performance pattern into the performance pattern storing area. To transmit the information on the determined winning start performance pattern to the image control board  150  and the lamp control board  140 , the sub CPU  120   a  further sets a performance pattern specification command based on the determined winning start performance pattern into the transmission buffer of the sub RAM  120   c.    
     At step S 1680 , the sub CPU  120   a  checks whether the command stored in the reception buffer is a bonus prize hole open specification command. 
     If the command stored in the reception buffer is a bonus prize hole open specification command, the sub CPU  120   a  shifts the processing to step S 1681 . If not a bonus prize hole open specification command, the sub CPU  120   a  shifts the processing to step S 1690 . 
     At step S 1681 , the sub CPU  120   a  performs jackpot performance pattern determination processing to determine a jackpot performance pattern. 
     Specifically, the sub CPU  120   a  determines the jackpot performance pattern on the basis of the bonus prize hole open specification command, and sets the determined jackpot performance pattern into the performance pattern storing area. To transmit the information on the determined jackpot performance pattern to the image control board  150  and the lamp control board  140 , the sub CPU  120   a  further sets a performance pattern specification command based on the determined jackpot performance pattern into the transmission buffer of the sub RAM  120   c.    
     At step S 1690 , the sub CPU  120   a  determines whether the command stored in the reception buffer is an ending command. 
     If the command stored in the reception buffer is the ending command, the sub CPU  120   a  shifts the processing to step S 1691 . If not an ending command, the sub CPU  120   a  ends the command analysis processing. 
     At step S 1691 , the sub CPU  120   a  performs winning end performance pattern determination processing to determine a winning end performance pattern. 
     Specifically, the sub CPU  120   a  determines the winning end performance pattern on the basis of the ending command, and sets the determined winning end performance pattern into the performance pattern storing area. To transmit the information on the determined winning end performance pattern to the image control board  150  and the lamp control board  140 , the sub CPU  120   a  further sets a performance pattern specification command based on the determined winning end performance pattern into the transmission buffer of the sub RAM  120   c . After the completion of the processing, the command analysis processing ends. 
     Referring to  FIG. 17 , the main processing of the image control board  150  will be described. 
     When power is supplied from the power supply board  170 , system reset occurs in the host CPU  150   a . The host CPU  150   a  performs the following main processing. 
     At step S 1710 , the host CPU  150   a  performs initialization processing. In the processing, the host CPU  150   a  loads a main processing program from the host ROM  150   c  in response to the power-on, and gives instructions for the initial setting of various modules of the host CPU  150   a  and the VDP  2000 . 
     For the initial setting of the VDP  2000 , the host CPU  150   a  performs following steps.
     (1) Giving an instruction to generate a video signal (set 1 into the zeroth bit of the display register) in order to instruct the display circuit to create and output a video signal.   (2) Setting predetermined initial value data into the decompression register in order to make the decompression circuit decompress and expand frequently-used image data (such as image data on the performance symbols  36 ) into the expansion storing area  153   b  of the VRAM  153 .   (3) Outputting an initial value display list in order to make the drawing circuit draw initial value image data (such as a text image “Starting up”).   

     At step S 1720 , the host CPU  150   a  performs drawing execution start processing. In the processing, the host CPU  150   a  sets drawing execution start data into the drawing register in order to instruct the VDP  2000  to execute drawing based on the previously-output display list. 
     More specifically, on startup, the VDP  2000  is instructed to execute drawing based on the initial value display list that is output in the foregoing step S 1710 . In normal routine processing, the VDP  2000  is instructed to execute drawing based on a display list that is output at S 1750  to be described later. 
     At step S 1730 , the host CPU  150   a  performs performance instruction command analysis processing to analyze a performance instruction command transmitted from the performance control board  120  (command stored in a reception buffer of the host RAM  150   b ). 
     When the image control board  150  receives a command transmitted from the performance control board  120 , not-shown command reception interrupt processing occurs in the image control board  150 , whereby the received command is stored into the reception buffer. Subsequently, the processing of analyzing the received command is performed in this step S 1730 . 
     The performance instruction command analysis processing determines whether a performance instruction command is stored in the reception buffer. If there is no performance instruction command stored in the reception buffer, the host CPU  150   a  simply shifts the processing to step S 1740 . 
     If a performance instruction command is stored in the reception buffer, the host CPU  150   a  reads the new performance instruction command. On the basis of the loaded performance instruction command, the host CPU  150   a  determines one or a plurality of animation groups to perform, and determines an animation pattern from each animation group. After the determination of the animation pattern(s), the host CPU  150   a  erases the loaded performance instruction command. 
     At step S 1740 , the host CPU  150   a  performs animation control processing. In the processing, the host CPU  150   a  updates the addresses of various animation scenes on the basis of a scene “switch counter,” the “wait frame,” and a “frame counter” which are updated in step S 2210  to be described later, and the animation pattern(s) determined in the foregoing step S 1730 . 
     At step S 1750 , the host CPU  150   a  generates a display list from single-frame display information (sprite ID number, display position, and the like) on the animation scenes at the updated addresses, depending on the priority (order of drawing) of the animation groups to which the animation scenes belong. 
     After the generation of the display list is completed, the host CPU  150   a  outputs the display list to the VDP  2000 . 
     The display list output here is stored into the display list storing area  153   a  of the VRAM  153  through the CPU I/F of the VDP  2000 . 
     At step S 1760 , the host CPU  150   a  determines whether “FB switch flag=01” or not. 
     The “FB switch flag=01” holds if the drawing of the previous display list has been completed by a V blank interrupt which occurs at intervals of 1/60 sec (approximately 16.6 ms). That is, at step S 1760 , the host CPU  150   a  determines whether the previous drawing has been completed. 
     If “FB switch flag=01,” the host CPU  150   a  shifts the processing to step S 1770 . If “FB switch flag=00,” the host CPU  150   a  waits until “FB switch flag=01.” 
     At step S 1770 , the host CPU  150   a  sets “FB switch flag=00” (resets the FB switch flag “off”), and shifts the processing to step S 1720 . 
     Subsequently, the host CPU  150   a  repeats the processing of steps S 1720  to S 1770  until a predetermined interrupt occurs. 
       FIG. 18  is a flowchart showing the detailed procedure of performance control processing to be performed by the performance control unit of the game machine which is configured through the application of the game machine, the performance control method, and the performance control program according to the embodiment of the present invention. 
     In  FIG. 18 , the performance control unit  200  decides whether the display request received is one for a performance using a three-dimensional performance image that is obtained by imaging and mapping three-dimensional objects arranged in the three-dimensional virtual space from the point of view of the virtual camera (S 1801 ). 
     The point of view of the virtual camera refers to the line of sight of the operation target, such as that of a character object in the case of a performance where the character object is operated. The “three-dimensional objects” refer to what can be seen from the character object. 
     If the display request received is other than for a three-dimensional image (NO at S 1801 ), the performance control unit  200  performs display processing to draw the performance image based on the display request and display the performance image on the display (S 1802 ). 
     On the other hand, if the display request received is for a three-dimensional image (YES at S 1801 ), the performance control unit  200  reads the “two-dimensional map information” (hereinafter, also referred to as “2D map”) which shows the range of movement on a vertical and horizontal two-dimensional plane where the character object having the point of view resulting from the virtual camera in the three-dimensional virtual space moves in the three-dimensional virtual space (S 1803 ). 
     Examples of the two-dimensional map information include the map information shown in  FIGS. 7 ,  21 ,  22 , and  23 . The map information is configured by dividing the vertical and horizontal two-dimensional plane in the three-dimensional virtual space into a plurality of sections (also referred to as “blocks”). 
     Reading the two-dimensional map information, the performance control unit  200  then reads the position information on the location of the virtual camera which serves as the point of view of the character object (S 1804 ). 
     The position information on the virtual camera may be position information that is given by initial setting in advance, or position information that is stored after the virtual camera is moved and operated by other display requests. The position information is specified in terms of three-dimensional coordinates in the three-dimensional virtual space, or specified by a section of the two-dimensional map information to which the virtual camera belongs. 
     When specified in terms of three-dimensional coordinates, the position information on the virtual camera is expressed like “coordinates (X,Y,Z),” for example. When specified by the section of the two-dimensional map information, it is expressed by a “section number” that identifies the section. 
     Next, the performance control unit  200  places the item object in any one of the sections constituting the two-dimensional map information (S 1805 ). The detailed procedure of the setting processing is shown in the flowcharts of  FIGS. 19 and 20 , which will be described later. 
     After the section to place the item object is set by such processing, the performance control unit  200  sets the layer to place the item object among the layers that constitute the section (S 1806 ). Here, the performance control unit  200  may select and set the layer to place the item object at random. The layer to place the item object may be set to one specified in advance. 
     After the setting of the section and layer to place the item object, the performance control unit  200  enables the acceptance of operations on the virtual camera (character object) (S 1807 ). 
     In such a state, the performance control unit  200  decides whether a camera operation is made by the player (S 1808 ). If the virtual camera is operated (YES at S 1808 ), the performance control unit  200  calculates the “block-to-block distance” between the section to which the virtual camera operated and moved belongs and the section in which the item object is placed (S 1809 ). The block-to-block distance can be expressed by the vertical distance and the horizontal distance in the two-dimensional map information. For example, a block-to-block distance of [vertical 2, horizontal 3] indicates that the section of the item object and the section to which the virtual camera belongs have a distance of two sections in the vertical direction and a distance of three sections in the horizontal direction. 
     The performance control unit  200  determines whether the “block-to-block” distance calculated is “0” (S 1810 ). If the “block-to-block distance” is “0,” i.e., if the block-to-block distance is expressed as [vertical 0, horizontal 0] in the vertical and horizontal directions, the performance control unit  200  then calculates the “layer distance” between the layer where the point of view of the virtual camera is and the layer where the item object is placed (S 1811 ). 
     The performance control unit  200  decides whether the layer distance is “0” (S 1812 ). If the point of view of the virtual camera is changed to the layer where the item object is placed and the layer distance is thus “0” (YES at S 1812 ), i.e., if the point of view of the virtual camera is in the layer where the item object is placed, the performance control unit  200  determines that the character object with the point of view of the virtual camera wins the item object (S 1813 ). 
     The performance control unit  200  then decides whether it is specified to provide a “special performance” in response to the winning of the item object (S 1814 ). If it is decided to be specified to provide a “special performance” (YES at S 1814 ), the performance control unit  200  displays a performance image for the “special performance” (S 1815 ). 
     If it is not specified to provide a “special performance” (NO at S 1814 ), the performance control unit  200  provides a normal performance. 
     After the end of such a performance, the performance control unit  200  disables operations on the virtual camera (S 1816 ), and ends the processing of this flowchart. 
     Now, take the following cases including a case where a camera operation on the virtual camera (character object) is enabled, and the decision whether or not an operation on the virtual camera is accepted (S 1808 ) shows that no operation on the virtual camera is accepted (NO at S 1808 ); a case where camera operation on the virtual camera is accepted, and the “block-to-block distance” between the section to which the virtual camera operated and moved belongs and the section in which the item object is placed is not “0” (NO at S 1810 ); and a case where the “block-to-block distance” is “0” but the “layer distance” is not (NO at S 1812 ). In such cases, the performance control unit  200  then decides whether a performance based on the display request is continuing (S 1817 ). 
     If the performance based on the display request is decided to be continuing (YES at S 1817 ), the performance control unit  200  decides whether the performance continuing is a specific performance (S 1821 ). The specific performance refers to a reach performance that precedes a “progressive jackpot performance” or the like to be provided when the character object wins the item object. The performance control unit  200  decides whether such a reach performance is continuing. 
     If the performance based on the display request is not decided to be continuing (NO at S 1817 ), the performance control unit  200  decides whether a termination condition for the performance based on the display request is satisfied (S 1818 ). The termination condition applies in cases such as when ending the game. If the game is to be ended (YES at S 1818 ), the performance control unit  200  disables camera operations (S 1816 ) and ends the processing of this flowchart. 
     If the termination condition is not satisfied (NO at S 1818 ), the performance control unit  200  stores the position information on the virtual camera (S 1819 ), initializes the position of the point of view of the virtual camera to the initial position (S 1820 ), and ends the processing of this flowchart. 
     If the specific performance is not continuing (NO at S 1821 ), the performance control unit  200  repeats the processing to decide whether an operation on the virtual camera is accepted (S 1808 ) and the subsequent processing. 
     If the decision whether the specific performance is continuing shows that the specific performance is continuing (YES at S 1821 ), the performance control unit  200  then decides whether the remaining time to the end of the specific performance is less than or equal to a predetermined time specified in advance (S 1822 ). If the remaining time is not less than nor equal to the predetermined time (NO at S 1822 ), i.e., the remaining time is more than the predetermined time and the character object can win the item object by operations on the virtual camera, then the performance control unit  200  repeats the processing to decide whether an operation on the vertical camera is accepted (S 1808 ) and the subsequent processing. 
     On the other hand, if the remaining time to the end of the specific performance is less than or equal to the predetermined time (YES at S 1822 ), the performance control unit  200  decides whether the item object needs to be won in order to provide a performance that follows the specific performance (S 1823 ). 
     If the item object needs to be won (YES at S 182 ), i.e., if the performance that follows the specific performance is provided when the character object wins the item object, the performance control unit  200  moves the virtual camera, or the point of view of the character object, to the section where the item object is placed, and changes the point of view of the virtual camera to the layer where the item object is placed (S 1824 ). 
     This makes the character object win the item object (S 1813 ). Subsequently, the performance control unit  200  provides the performance for the situation where the item object is won. 
     If it is not decided necessary to win the item object (NO at S 1823 ), the performance control unit  200  displays a performance image for the “specific performance” (S 1815 ). 
       FIG. 19  is a flowchart showing the detailed procedure of processing to place the item object into any one of the sections constituting the two-dimensional map information, the processing being included in the performance control processing shown in  FIG. 18 . 
     In  FIG. 19 , the performance control unit  200  decides whether the display request is given during a reach performance (S 1901 ). If the display request is not given during a reach performance (NO at S 1901 ), the performance control unit  200  selects any one of sections specified in advance (S 1902 ). 
     On the other hand, if the display request is given during a reach performance (YES at S 1901 ), the performance control unit  200  acquires the result of drawing of the drawing processing in the reach performance (S 1903 ). 
     The performance control unit  200  decides whether the result of drawing hits a “jackpot” or not (S 1904 ). If a “jackpot” (YES at S 1904 ), the performance control unit  200  selects any one of sections that are accessible by the player&#39;s operations on the virtual camera (S 1905 ). 
     On the other hand, if the result of drawing is not a “jackpot” (NO at S 1904 ), the performance control unit  200  selects any one of sections that are not accessible by operating the virtual camera (S 1906 ). 
     That is, the winning of the item object is precluded even with the movement of the virtual camera (character object). 
       FIG. 20  is a flowchart showing the detailed procedure of processing to place the item object into any one of the sections constituting the two-dimensional map information, the processing being included in the performance control processing shown in  FIG. 18 .  FIG. 20  shows another example of the processing shown in  FIG. 19 . 
       FIG. 20  deals with the procedure that includes pre-read processing. Suppose that game balls enter a start hole and the processing to draw a combination of performance symbols for the entries of the game balls is reserved (reserved state). The pre-read processing refers to pre-reading the results of drawing in such a case by performing the processing of reserved combination drawing in advance. 
     In  FIG. 20 , the performance control unit  200  initially pre-reads the results of reserved combination drawing (S 2101 ), and decides whether the results of drawing pre-read include a “jackpot” (S 2102 ). 
     If the pre-read results of combination drawing are decided to include a “jackpot” (YES at S 2102 ), the performance control unit  200  acquires reservation information which describes the reserved state corresponding to the result of drawing of the “jackpot” (S 2103 ). The reservation information includes information that shows the reserved combination drawing of what number wins the result of drawing of the “jackpot” among all the reservations for the combination drawing corresponding to the entries of game balls into the start hole. 
     The performance control unit  200  then determines a section that can be accessed by the character object when the virtual camera (character object) is operated by the player as many times as the number of reservations in the reservation information, as the section to place the item object (S 2104 ). 
     If the results of drawing pre-read do not include a “jackpot” at all (NO at S 2102 ), the performance control unit  200  selects any one of a plurality of sections specified in advance (S 2105 ). 
       FIGS. 21 ,  22 , and  23  show two-dimensional map information divided in a plurality of sections on which the vertical and horizontal two-dimensional plane where the character object having the point of view of the virtual camera in the three-dimensional virtual space moves in the three-dimensional virtual space is superposed. 
     In the diagrams, the diagonally shaded areas represent, for example, building objects in the three-dimensional virtual space. The character represents the virtual camera (character object) in the three-dimensional virtual space. The diagrams show that when the virtual camera is moved in the three-dimensional virtual space, the character moves on the map information. The character can move to areas where no building object is placed. 
     For example,  FIG. 21  shows five routes for the character object to move along, namely, “route  1 - 1 , ” “route  1 - 2 , ” “route  1 - 3 , ” “route  1 - 4 , ” and “route  1 - 5 .” The “route  1 - 1 ”shows the path of movement to a vertically upper section in the sections of the two-dimensional map information. The “route  1 - 2 ”shows the path of movement to a diagonally upper right section in the sections of the two-dimensional map information. The “route  1 - 3 ”shows the path of movement to a horizontally right section in the sections of the two-dimensional map information. The “route  1 - 4 ”shows the path of movement to a diagonally lower right section in the sections of the two-dimensional map information. The “route  1 - 5 ”shows the path of movement to a vertically lower section in the sections of the two-dimensional map information. 
       FIG. 22  shows the state when the “route  1 - 2 ” is selected from the routes of  FIG. 21 . Here, the character object is moved one section to the right and one section vertically upward from the one to which the character object of  FIG. 21  belongs. 
     Like  FIG. 21 ,  FIG. 22  shows six routes for the character object to move along, “route  2 - 1 , ” “route  2 - 2 , ” “route  2 - 3 ,” “route  2 - 4 , ” “route  2 - 5 ,” and “route  2 - 6 .” 
       FIG. 23  shows the state when the “route  2 - 1 ” is selected from the routes of  FIG. 22 . The character object is moved one section vertically upward from the section to which the character object of  FIG. 22  belongs. 
     Like  FIGS. 21 and 22 ,  FIG. 23  shows five routes for the character object to move along, “route  3 - 1 ,” “route  3 - 2 ,” “route  3 - 3 ,” “route  3 - 4 ,” and “route  3 - 5 .” 
     Of the five routes, the “route  3 - 2 ” can be taken to reach the section where the item object is placed. 
     Each of the sections constituting the two-dimensional map information of  FIGS. 21 ,  22 , and  23  seen above has layers like shown in  FIG. 24 . Such layers represent the positions of the point of view of the virtual camera when the virtual camera is directed upward, horizontally, and downward in the three-dimensional virtual space. 
     For example,  FIG. 24  shows the layers of the section where the item object is placed in  FIGS. 21 ,  22 , and  23 . The three layers are composed of a first layer at the bottom, a second layer in the middle, and a third layer at the top. 
     By initial setting, the virtual camera is directed to the second layer in front. The performance button  35  shown in  FIGS. 8 and 25  can be depressed to change the layer of the point of view of the virtual camera in each section. When the performance button  35  is depressed with the point of view set to the second layer, the point of view is initially changed to the first point of view where the first layer is seen. The next depression of the performance button  35  changes the point of view to the second point of view where the second layer is seen. The next depression of the performance button  35  changes the point of view to the third point of view where the third layer is seen. The next depression changes the point of view to the second point of view where the second layer is seen. 
     That is, the layers are changed like “the second layer→the first layer→the second layer→the third layer→the second layer→the first layer→the second layer→the third layer→the second layer→the first layer→ . . . ” in succession. 
     The item object is placed in the third layer. In the state shown in  FIG. 23 , the “route  3 - 2 ” can be taken to reach that section, and the performance button  35  can be depressed “three times” successively to change the point of view of the virtual camera to the first layer. 
     Consequently, the virtual camera (character object) wins the item object, and the performance based on the item object is provided. 
     The embodiment described above is just one embodiment of the present invention. The present invention is not limited to such an embodiment, and modifications may be made as appropriate without changing the gist of the invention. 
     It should be noted that the present invention may also provide a computer that performs the foregoing processing, by installing programs for implementing the foregoing means from a recording medium (such as CD-ROM and DVD-ROM) storing the programs into the computer and executing the same. Such a computer includes a CPU (Central Processing Unit), a ROM (Read Only Memory), a RAM (Random Access Memory), and a hard disk which are connected through a system bus. The CPU performs processing according to the programs stored in the ROM or the hard disk, using the RAM as the work area. 
     The medium for supplying the programs may be a communication medium (a medium that temporarily or fluidly retains the programs, such as a communication line and a communication system). For example, the programs may be posted to a BBS (Bulletin Board Service) of a communication network and distributed through communication lines.