Abstract:
A game system with a high entertainment value, in which a plurality of player character are played by a plurality of players, and a game program for such a game system are provided. A plurality of individual displays provided to players and a common display commonly provided to all players are provided. Each player character is moved between a first game map and a second game map upon satisfaction of a predetermined condition. A player character located on the first game map and at least a part of the first game map are displayed on the common display. A player character located on the second game map and at least a part of the second game map are displayed on an individual display provided to a player operating that player character.

Description:
FIELD OF THE INVENTION  
         [0001]    The present invention relates to game systems and game programs. More specifically, the present invention relates to a game system and a game program having a plurality of display mechanisms.  
         BACKGROUND AND SUMMARY OF THE INVENTION  
         [0002]    A game system having a plurality of display mechanisms is disclosed in Japanese Patent Laid-Open Publication No. 2003-53038. This game system includes a first display for displaying a first game world and second display for displaying a second game world. While a player character is located in the first game world, the player character is displayed on the first display. While a player character is located in the second game world, the player character is displayed on the second display.  
           [0003]    There have been game systems in which a plurality of players operate a plurality of player characters. In such game systems, players play a game influencing each other through cooperation or battle, thereby increasing the game entertainment value.  
           [0004]    The game system disclosed in the above Japanese Patent Laid-Open Publication No. 2003-53038 basically assumes that only one player plays a game. No consideration is given to applying the game system to a case where a plurality of player characters appear.  
           [0005]    Therefore, a feature of the present exemplary embodiments is to provide a game system with a high entertainment value and having a plurality of displays, wherein a plurality of player characters are controlled by a plurality of players, and a game program for such a game system.  
           [0006]    The present exemplary embodiments have the following features to attain the feature mentioned above.  
           [0007]    A first aspect of the present exemplary embodiments is directed to a game system (game system  10 ; hereinafter, a term(s) in parentheses indicate(s) the corresponding component(s) in the embodiment described further below) to be played by a plurality of players. This game system includes a plurality of operating mechanisms (operation switches  36  provided to each of game machines  30   a  through  30   d ) provided to the players, a plurality of individual displays (LCD  35  provided to each of the game machines  30   a  through  30   d ) provided to the players, and a common display (television monitor  60 ) commonly provided to the players. In this game system, a plurality of player characters (player characters  110   a  through  110   d ) appear on game maps, and these player characters are controlled by each corresponding player operating each corresponding operating mechanism. The game system includes: first game map data storage devices (DVD  50  and RAM  22 ) which include locations for storing data for displaying a first game map (ground map  100 ); second game map data storage devices (DVD  50  and RAM  32 ) which include locations for storing data for displaying at least one second game map (dungeon map  200 , house map, or castle map); inter-game-map movement processing control mechanism (CPU  21  executing steps S 107 , S 109 , S 113 , and S 115 ) which moves the player characters individually between the first game map and the second game map upon satisfaction of a predetermined condition; common display control mean mechanism (CPU  21  executing steps S 139  and S 147 ) which displays player characters located on the first game map and at least a part of the first game map on the common display; and individual display control mechanism (CPU  31  executing steps S 217  and S 221 ) which controls the display of a player character located on the second game map and at least a part of the second game map on the individual display provided to a player operating the player character located on the second game map. Note that the number of common displays provided is typically one. Also, in general, the second game map is different from the first game map.  
           [0008]    Each player character is controlled by each of the plurality of players operating each operating mechanism. Also, individual displays are provided for each player. The player character located on the first game map is displayed on the common display, while the player character located on the second game map is displayed on the individual display of the player operating that player character.  
           [0009]    According to the first aspect, it is possible to provide a game with a high entertainment value in which a plurality of player characters can appear and disappear among a plurality of displays. Also, the first game map displayed on the common display and the second game map displayed on the individual displays are provided. The player character that has been displayed on the common display can disappear therefrom and then appear on the individual displays, and the player character that has been displayed on the individual display can disappear therefrom and then appear on the common display. This makes the player feel as if his or her player character is moving among the game maps. Also, with an individual display being provided for each player, each player character can freely move among the game maps.  
           [0010]    In a second aspect, the first game map and the second game map each include at least one connecting point (dungeon entrances  130   a  and  130   b , house entrance  130   c , castle entrance  130   d , or ground-map entrance  230   a ). The connecting point (dungeon entrances  130   a  and  130   b , house entrance  130   c , or castle entrance  130   d ) of the first game map corresponding to a predetermined point (ground-map entrance  230   a , dungeon-map coordinates (X 1 , Y 1 ), ground-map entrance X, or ground-map entrance Y) on the second game map and the connecting point (ground-map entrance  230   a , ground-map entrance X, or ground-map entrance Y) of the second game map corresponding to a predetermined point (dungeon entrances  130   a , house entrance  130   c , or castle entrance  130   d ) on the first game map (FIG. 7). Upon arrival of the player character at the connecting point on the first game map, the inter-game-map movement control mechanism moves the player character to the predetermined point on the second game map corresponding to the connecting point (CPU  21  executing steps S 107  and S 109 ). Also, upon arrival of the player character at the connecting point on the second game map, the inter-game-map movement control mechanism moves the player character to the predetermined point on the first game map corresponding to the connecting point (CPU  21  executing steps S 113  and S 115 ). The connecting point is a point upon arrival at which the player character moves to another game map (a point as an entrance to anther game map).  
           [0011]    According to the second aspect, upon arrival at the connecting point, the player character moves to another game map. This clarifies the condition on which the player character moves, thereby facilitating the progress of the game.  
           [0012]    In a third aspect, the second game map data storage device stores a plurality of said second game maps (dungeon map  200 , house map, and castle map). The connecting point on the first game map corresponds to a predetermined point on any one of the plurality of said second game maps (FIG. 7).  
           [0013]    According to the third aspect, upon arrival at a connecting point on the first game map, the player character does not always move to the same single second game map. Upon arrival at one connecting point, the player character moves to a point on one second game map, but upon arrival at another connecting point, the player character moves to a point on another second game map. With this, it is possible to provide a game with a high entertainment value.  
           [0014]    In a fourth aspect, the second game map data storage means stores a plurality of said second game maps ▭dungeon map  200 , house map, and castle map). Based on a second game map on which a player character is located, the individual display control mechanism selects, from the plurality of said second game maps, the second game map on which the player character is located, and causes the selected second game map to be displayed on the individual display provided to a player who operates the player character located on the second game map.  
           [0015]    According to the fourth aspect, an individual display is provided for each player. Also, each individual display can display each different second game map. Therefore, each player character can freely move to each different second game map. Furthermore, since each display can display various game maps, it is possible to provide a versatile game with a high entertainment value.  
           [0016]    In a fifth aspect, the common display control mechanism determines a display range of the first game map so that all player characters located on the first game map can be displayed on the common display (CPU  21  executing step S 137 ).  
           [0017]    According to the fifth aspect, the common display displays all player characters located on the first game map. Therefore, all player characters are displayed on at least any of the displays, thereby avoiding inconvenience.  
           [0018]    In a sixth aspect, each point on the first game map corresponds to any one point on the second game map. The common display control mechanism generates a predetermined display ( 150   a ,  150   b ) of a player character located on the second game map, at a point on the first game map corresponding to a point on the second game map at which the player character is located (CPU  21  executing step S 141 ).  
           [0019]    According to the sixth aspect, by viewing a game image displayed on the common display, it is possible to know the location of the player character on the second game map. Also, the correspondence between the first game map and the second game map is presented to the user, thereby enabling a game image with a high entertainment value to be displayed.  
           [0020]    In a seventh aspect, in addition to the player characters, an enemy character can appear on the game maps. Also, each point on the first game map corresponds to any one point on the second game map. A player character located on the first game map can have an influence on any other player character and an enemy character located on the second game map, and a player character located on the second game map can have an influence on any other player character and an enemy character located on the first game map (CPU  21  executing step S 125 ).  
           [0021]    According to the seventh aspect, it is possible to provide a game with a high entertainment value in which player characters can have an influence on each other among different game maps.  
           [0022]    In an eighth aspect, the game system further includes a plurality of portable game machines (second game machines  30   a  through  30   d ) provided to the players. The operating switches included in each of the portable game machines functions as the operating mechanisms, and the LCD display included in each of the portable game machines functions as the display.  
           [0023]    According to the eighth aspect, with the use of portable game machines, the game system of the present exemplary embodiments can be easily structured.  
           [0024]    A ninth aspect is directed to a computer-readable recording medium for recording a game program for a game system to be played by a plurality of players. This game system includes a plurality of operating mechanisms provided to the players, a plurality of individual displays provided to the players, and common display commonly provided to the players. In the game system, a plurality of player characters appear on game maps, and these player characters are controlled by each corresponding player operating each corresponding operating mechanisms. The game program causes the game system to function as: first game map data storage device which stores data for displaying a first game map; second game map data storage device which stores data for displaying at least one second game map; inter-game-map movement control mechanism which moves the player characters individually between the first game map and the second game map upon satisfaction of a predetermined condition; a common display control mechanism which displays player characters located on the first game map and at least a part of the first game map on the common display; and individual display control mechanism which displays a player character located on the second game map and at least a part of the second game map on individual displays provided to a player corresponding to the player character located on the second game map.  
           [0025]    According to the ninth aspect, the effects achieved by the first  5  aspect can also be achieved.  
           [0026]    These and other objects, features, aspects and advantages of the present exemplary embodiments will become more apparent from the following detailed description of the present exemplary embodiments when taken in conjunction with the accompanying drawings. 
       
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0027]    [0027]FIG. 1 is an external view of a game system  10  according to one embodiment of the present invention;  
         [0028]    [0028]FIG. 2 is a block diagram illustrating the game system  10 ;  
         [0029]    [0029]FIG. 3 is an illustration for describing a ground map;  
         [0030]    [0030]FIG. 4 is an illustration for describing a movement of a display area  150  upon a movement of a player character  110 ;  
         [0031]    [0031]FIG. 5 is an illustration for describing a change in size of the display area  150  when player characters  110  are distanced far apart from each other;  
         [0032]    [0032]FIG. 6 is an illustration for describing a dungeon map; FIG. 7A and 7B are illustrations for describing tables containing connecting points;  
         [0033]    [0033]FIG. 8 is an illustration showing examples of game images displayed on a television monitor  60  and LCDs  35 ;  
         [0034]    [0034]FIG. 9 is a flowchart of a main process performed by a CPU  21  of a first game machine  20  and a CPU  31  of a second game machine  30 ;  
         [0035]    [0035]FIG. 10 is a flowchart showing a first half of a game process preformed by the CPU  21  of the first game machine  20 ; FIG. 11 is a flowchart showing a latter half of the game process performed by the CPU  21  of the first game machine  20 ; FIG. 12 is a flowchart showing a game process performed by the CPU  31  of the second game machine  31 ; and  
         [0036]    [0036]FIG. 13 is an external view of a system according to a modification of the embodiment of the present invention. 
     
    
     DESCRIPTION OF THE PREFERRED EMBODIMENT  
       [0037]    [0037]FIG. 1 is an external view of a game system  10  according to one embodiment of the present invention. The game system  10  includes a first game machine  20 , second game machines  30   a  through  30   d , cables  40   a  through  40   d  connecting the first game machine  20  and each of the second game machines  30  ( 30   a  through  30   d ), a DVD  50 , a television monitor  60 , and a cable  70  for connecting the first game machine  20  and the television monitor  60  to each other. The first game machine  20  is a fixed-type game machine. The second game machines  30   a  through  30   d  are portable-type game machines. The first game machine  20  has four connectors  27  ( 27   a  through  27   d ) each connectable to a game controller not shown. The game machines  30   a  through  30   d  are connected via the cables  40   a  through  40   d  to these connectors  27   a  through  27   d , respectively. The first game machine  20  has exchangeably inserted therein the DVD  50 . Video and audio outputs from the first game machine  20  are produced via the cable  70  to the television monitor  60 . The second game machines  30   a  through  30   d  each include an LCD  35  and operation switches  36   a  through  36   c.    
         [0038]    [0038]FIG. 2 is a block diagram illustrating the game system  10 . The first game machine  20  includes a CPU  21 , RAM  22 , an image processing unit  23 , a DVD drive  25 , and a communication interface  26 , which are connected to each other via a bus. Furthermore, the image processing unit  23  has connected thereto an encoder  24 , from which a video signal is output via the cable  70  to the television monitor  60 . Still further, the communications interface  26  includes an operation data buffer  261  connected via connectors  27   a  through  27   d  and the cables  40   a  through  40   d  to the second game machines  30   a  through  30   d . Note that the image processing unit  23  is not necessarily required, and its function can be achieved by the CPU  21 .  
         [0039]    The DVD  50  has stored therein a game program and game data for the first game machine  20   b  and a game program and game data for the second game machines  30 . The game program and game data are read by the DVD drive  25  when appropriate, and are then stored in the RAM  22 . The CPU  21  executes a game process based on the data stored in an area of the RAM  22 . Game data resulting from the execution of the game process by the CPU  21  is stored in another area of the RAM  22 . The image processing unit  23  generates display data based on the data generated by the CPU  21  and then stored in the RAM  22 , and then outputs the generated display data to the encoder  24 . The encoder  24  outputs a video signal via the cable  70  to the television monitor  60 .  
         [0040]    Data to be transmitted from the first game machine  20  and the second game machines  30   a  through  30   d  is output from the CPU  21  via the communications interface  26 , the connectors  27   a  through  27   d , and the cables  40   a  through  40   d . Data to be transmitted from the second game machines  30   a  through  30   d  to the first game machine  20  is output to the CPU  21  via the cables  40   a  through  40   d , the connectors  27   a  through  27   d , and the communications interface  26 . Operation data of the operation switches  36  of each of the second game machines  30   a  through  30   d  is transmitted via the cables  40   a  through  40   d  and the connectors  27   a  through  27   d , respectively, for storage in the operation data buffer  261 .  
         [0041]    Each of the second game machines  30  includes a CPU  31 , RAM  32 , an image processing unit  33 , the operation switches  36 , and a communications interface  37 , which are connected to each other via a bus. Furthermore, the image processing unit  33  has connected thereto an LCD driver  34 , to which the LCD  35  is connected. Still further, the communications interface  37  is connected via the connector  38  and the cable  40  to the first game machine  20 .  
         [0042]    Of the data stored in the DVD  50 , the game program and game data for the second game machines  30  is read by the first game machine  20 , transferred to the second game machines  30 , and is then stored in an area of the RAM  32 . The CPU  31  reads the game program and game data stored in the RAM  32  for execution of a game process. At this time, game data newly generated by the CPU  31  is stored in another area of the RAM  32 . The image processing unit  33  generates display data based on the data generated by the CPU  31  and then stored in the RAM  32 , and then outputs the generated display data to the LCD driver  34 . The LCD driver  34  drives the LCD  35  for image display. Data to be transmitted to the first game machine  20  is transmitted from the CPU  31  via the communications interface  27 , the connector  38 , and the cable  40 . Also, data to be transmitted from the first game machine  20  is received by the CPU  31  via the connector  38  and the communications interface  37 . Note that the image processing unit  33  is not necessarily required, and its function can be achieved by the CPU  31 .  
         [0043]    Furthermore, the second game machines  30   a  through  30   d  have the same structure.  
         [0044]    An outline of a game executed in the above-described game system is illustrated in FIGS. 3 through 6, and FIGS. 7A and 7B. This game proceeds with the use of a ground map as a main map, and a dungeon map, a house map, and a castle map as sub-maps, in a manner such that an operation of the control switches  36  by each players controls the movement of each player character so that the player character is appropriately moved among the main map and the sub maps to beat an enemy character or get an item.  
         [0045]    Each player is given a second game machine  30 . Since the second game machine  30  is provided with the LCD  35 , each player has his or her own screen (LCD 35 ). In the present embodiment, it is assumed that there are four players (players a through d) and four player characters  110   a  through  110   d . The player a operating the player character  110   a  is given the second game machine  30   a . The player b operating the player character  110   b  is given the second game machine  30   b . The player c operating the player character  110   c  is given the second game machine  30   c . The player d operating the player character  110   d  is given the second game machine  30   d . Each player operates the operation switches  36  of his or her second game machine  30  to control his or her own player character. The state of the main map is displayed on the television monitor  60 . The state of a sub map is displayed on the LCD  35  of each second game machine  30 .  
         [0046]    While the player character is located on a sub map, the screen (LCD  35 ) dedicated to the player operating the player character has displayed thereon the sub map including the player character. While the player character is located on the main map, the screen (LCD  35 ) dedicated to the player operating the player character may be blank, or may have displayed thereon a sentence such as “the character is on the ground map” or “the character is being displayed on the television monitor”.  
         [0047]    To view the state of the main map (while the player character is located on the main map, for example), each player plays the game as viewing the television monitor  60 . While the player character is located on a sub-map when the player desires to view the state of the sub-map, the player plays the game as viewing a display on the LCD of his or her own second game machine  30 .  
         [0048]    Each player character is displayed on the television monitor  60  while it is located on the main map. When the player character moves from the main map to a sub-map, the player character disappears from the television monitor  60 , and appears instead on the screen (LCD  35 ) dedicated to the player operating that player character. When the player character moves from the sub-map to the main map, the player character disappears from the LCD  35 , and appears instead on the display monitor  60 .  
         [0049]    [0049]FIG. 3 is an illustration showing the ground map  100 , which is an example of a first game map. The ground map is a map mainly used for playing the game. Therefore, in the following description, the ground map is also referred to as a main map. The ground map  100  is extended as shown in FIG. 3, having placed thereon the player characters  110   a  through  110   d  (in FIG. 3, all player characters are on the ground map), an enemy character  120 , dungeon-map entrances  130   a  and  130   b  to a dungeon map, which is one example of connecting points, a house-map entrance  130   c  to a house map, which is another example of connecting points, a castle-map entrance  130   d  to a castle map which is still another example of connecting points, a house object  140   a , and a castle object  140   b . The player characters  110   a  through  110   d  and the enemy character  120  are objects moving on the ground map. The connecting points  130   a  through  130   d , the house object  140   a , and the castle object  140   b  are unmoving objects fixed to each predetermined point on the ground map.  
         [0050]    This ground map is displayed on the television monitor  60 , but not entirely. That is, a partial area is set as a display area  150 , and a part of the ground map within the display area  150  and various objects including player characters placed on that part of the ground map are displayed on the television monitor  60 .  
         [0051]    Taking a predetermined point on the ground map as an origin, ground map coordinates are set. In the example of FIG. 3, the ground map coordinates are two-dimensional coordinates. When the ground map is a three-dimensional map, the ground map coordinates are three-dimensional coordinates.  
         [0052]    The television monitor  60  displays an area surrounding the player characters  110 . Therefore, the display area  150  can move as the player characters  110  move, which is illustrated in FIG. 4. As the player characters  110   a  through  110   d move in a lower-right direction on the ground map, the display area  150  moves in the lower-right direction accordingly.  
         [0053]    Furthermore, the television monitor  60  displays all player characters  110  located on the ground map. Therefore, when the player characters  110  move in different directions to become distanced far apart from each other, the display area  150  becomes enlarged as illustrated in FIG. 5. With such enlargement of the display area  150 , all player characters  110  located on the ground map are displayed on the television monitor  60 . Conversely, when the player characters  110  become less distanced apart from each other, the display area  150  is reduced. Note that the ground map and various objects thereon are displayed so as to become smaller when the display area  150  is enlarged, while they are displayed so as to become larger when the display area  150  is reduced.  
         [0054]    [0054]FIG. 6 is an illustration showing a dungeon map  200 , which is one example of a second game map. FIG. 6 illustrates a state of the dungeon map  200  changed from the state illustrated in FIG. 3 after the player characters  110   a  through  110   c  have moved thereto. In this state, the dungeon map  200  has placed thereon the player characters  110   a  and  110   c , the enemy character  120 , and a ground-map entrance  230   a  to the ground map. The player characters  110  and the enemy character  120  are moving objects, while the ground-map entrance  230   a  is an unmoving object fixed to a predetermined point on the dungeon map.  
         [0055]    The dungeon map is displayed on screens (LCDs  35 ) dedicated to the players operating the player characters located on that dungeon map. Here, what is displayed on each LCD  35  is not the entire dungeon map, but only a part thereof. In the state illustrated in FIG. 6, an area  240   a  covering a certain area surrounding the player character  110   a  is displayed on the screen (LCD  35  of the second game machine  30   a ) dedicated to the player a operating the player character  110   a . Also, an area  240   c  covering a certain area surrounding the player character  110   c  is displayed on the LCD  35  of the second game machine  30   c  dedicated to the player c operating the player character  110   c . The display area  240  moves as the corresponding player characters move. However, the size of the display area does not have to be changed.  
         [0056]    Taking a predetermined point on the dungeon map as an origin, dungeon map coordinates are set. In the example of FIG. 6, the dungeon map coordinates are two-dimensional coordinates. When the dungeon map is a three-dimensional map, the dungeon map coordinates are three-dimensional coordinates. The origin of the dungeon map corresponds to a predetermined point on the ground map. For example, the origin of the dungeon map corresponds to a point ( 20 ,  10 ) on the ground map (that is, X= 20 , Y=10). With this correspondence, it is possible to relate points on the dungeon map to points on the ground map. That is, in this example, a point (Xd, Yd) on the dungeon map corresponds to a point (Xd+20, Yd+10).  
         [0057]    The structures of the house map and the castle map are similar to that of the dungeon map, and therefore are not described herein.  
         [0058]    When the player character  110  on the ground map comes to the dungeon-map entrance  130   a  or  130   b , the player character  110  moves to the dungeon map illustrated in FIG. 6. Also, when the player character  110  on the dungeon map comes to the ground-map entrance  230   a , the player character  110  moves to the ground map illustrated in FIG. 3.  
         [0059]    Specifically, a process of moving upon coming to a connecting point is performed with reference to tables of FIGS. 7A and 7B. FIG. 7A is a table which defines points on the sub-maps to which the player character  110  moves upon coming to connecting points on the ground map. That is, the player character  110  moves from the ground map to any one of the sub-maps in accordance with this table. Specifically, upon coming to the point  130   a  on the ground map, the player-character  110  moves to the point  230   a  on the dungeon map. Upon coming to the point  130   b , the player character  110  moves to a point represented by coordinates (XI, Y 1 ) on the dungeon map. Furthermore, this table is referred to when the player character  110  comes to the house-map entrance  130   c  or the castle-map entrance  130   d  for moving to the corresponding point on the house map or the castle map.  
         [0060]    [0060]FIG. 7B is a table that defines points on the ground map to which the player character moves upon coming to connecting points on sub-maps. That is, the player character  110  moves from a sub-map to the ground map in accordance with this table. Specifically, upon coming to the point  230   a  on the dungeon map, the player character  110  moves to the point  130   a . Furthermore, this table is referred to when the player character  110  comes to a connecting point on the house map or the castle map for moving to the corresponding point on the ground map. Note that the player character can move from the point  130   b  to the dungeon map, but cannot return to the point  130   b  after moving from the point  130   b  to the dungeon map.  
         [0061]    [0061]FIG. 8 is an illustration showing examples of game images displayed on a television monitor  60  and LCDs  35  of the second game machines  30   a  through  30   d . The television monitor  60  displays a partial area of the ground map  100  (an area surrounding player characters located on the ground map) as a display area. Specifically, all player characters located on the ground map (in FIG. 8, the player characters  110   b  and  110   d ) are displayed. Furthermore, of the enemy characters  120  located on the ground map, an enemy character  120  located within the display area is displayed. Still further, of other objects (objects other than player characters and enemy characters) located on the ground map, an object located within the display area (in FIG. 8, the dungeon-map entrance  130   a ) is displayed. Still further, a part of the ground map within the display area is displayed.  
         [0062]    Also, the television monitor  60  may display marks  150   a  and  150   c  at locations on the ground map that correspond to the locations of player characters on a sub-map (in FIG. 8, the player characters  110   a  and  110   c , respectively). These marks  150  make it possible to achieve image representations such that the player characters located on the sub-map can be transparently viewed from the ground map (or such that the player characters located on the sub-map cast their shadows on the ground map). As described above, the locations on the ground map that correspond to those on the sub-map are calculated based on the correspondence of map coordinates. The mark  150   a  is a mark indicative of a location on the ground map corresponding to the location of the player character  110   a  located on the dungeon map. Similarly, the mark  150   c  is a mark indicative of a location on the ground map corresponding to the location of the player character  110   c  located on the dungeon map.  
         [0063]    Regarding the player characters  110  located on the sub-map (in FIG. 8, the player characters  110   a  and  110   c ), the screens dedicated to the players operating these player characters (in FIG. 8, the LCDs  35  of the second game machines  30   a  and  30   c ) each display the corresponding player character, a part of the dungeon map within an area surrounding the player character, and, any enemy character, any other player characters, and any other objects within that area.  
         [0064]    The screens dedicated to the players operating the player characters on the ground map (in FIG. 8, the player characters  110   b  and  110   d ), that is, the LCDs of the second game machines  30   b  and  30   d  in FIG. 8, do not display anything.  
         [0065]    In FIG. 8, the player characters  110   a  and  110   c  are located on the same sub-map (dungeon map). Alternatively, the player characters can be located on different sub-maps. For example, the player character  110   a  can be located on the dungeon map, while the player character  110   c  can be located on the castle map. In this case, the LCD  35  of the second game machine  30   a  displays the dungeon map, while the LCD  35  of the second game machine  30   c  displays the castle map.  
         [0066]    Furthermore, in FIG. 8, when the player characters  110   a  and  110   c  are coming close to each other within a predetermined distance on the dungeon map, the LCD  35  of the second game machine  30   a  may display the player character  110   c , while the LCD  35  of the second game machine  30   c  may display the player character  110   a.    
         [0067]    Still further, in FIG. 8, when the player character  110   b  moves to the dungeon-map entrance  130   a , the player character  110   b  disappears from the television monitor  60 , and then appears on the LCD  35  of the second game machine  30   b  together with the dungeon map.  
         [0068]    Still further, in FIG. 8, when the player character  110   a  moves to the ground-map entrance  230   a  illustrated in FIG. 6, the player character  110   a  disappears from the LCD  3  of the second game machine  30   a , and then appears on the television monitor  60 .  
         [0069]    [0069]FIG. 9 shows flowcharts for processes of programs executed on the first game machine  20  and each of the second game machines  30 . A flowchart shown on left in FIG. 9 shows a process of a program executed by the CPU  21  of the first game machine  20 , while a flowchart shown on right therein shows a process of a program executed by the CPU  31  of each of the second game machines  30 .  
         [0070]    In FIG. 9, when the first game machine  20  is powered on, an initializing process is performed. Then, in step S 1 , the game program and game data for the second game machines (for example, sub-map data) is read from the DVD  50 , and is then transmitted to the second game machines  30 . Subsequent to step S 1 , in step S 3 , the type of the player character is determined for each second game machine  30 . Then, in step S 5 , the determined type of the player character is transmitted to the respective second game machines  30 . Subsequent to step S 5 , it is determined in step S 7  whether all of the second game machines  30   a  through  30   d  have been processed in steps S 1  to S 5 . If they have not yet been processed, the procedure returns to step S 1  for processing a second game machine  30  not yet processed. That is, by repeating a series of steps S 1  to S 7 , the game program and game data for all of the second game machines  30   a  through  30   d  are transmitted, and the type of the player character of each of the second game machines  30   a  through  30   d  are determined and then transmitted. Then, the procedure goes to step S 9 .  
         [0071]    In step S 9 , the game program and game data (for example, ground map data) for the first game machine is read from the DVD  50 , and is then stored in the RAM  22 . Subsequent to step S 9 , in step S 11 , a game process is executed, which will be described further below with reference to FIGS. 10 and 11.  
         [0072]    In FIG. 9, when the second game machine  30  is powered on, an initializing process is performed. Then, in step S 21 , a process of receiving the game program and game data for the second game machines transmitted in the above-described step S 1  from the first game machine  20 , and storing the received program and data in the RAM  32  is performed. Subsequent to step S 21 , in step S 23 , a process of receiving the type of the player character transmitted in the above-described step S 5  from the first game machine  20  is performed. Subsequent to step S 23 , in step S 25 , each of the second game machines  30   a  through  30   d  causes its own LCD to perform a displaying process for presenting the type of the player character received in step S 23  to the player. Specifically, a name of the type of the player character, an image of the player character, and colors representing the player character are displayed to present, to the player, the type of the character which the player is going to operate. Subsequent to step S 25 , in step S 27 , a game process is performed, which will be described further below with reference to FIG. 12.  
         [0073]    [0073]FIGS. 10 and 11 is a flowchart showing the game process preformed in the above-described step  511  of FIG. 9 by the CPU  21  of the first game machine  20 . In this game process, first in step S 101 , the CPU  21  reads operation data of a second game machine  30   x  (first, a process is performed for a case where x=a, that is, operation data of the second game machine  30   a  is read, then x=b, x=c, and x=d. Hereinafter, descriptions are made for an example where x=a). Subsequent to step S 101 , it is determined in step S 103  whether the operation data read in step S 101  is operation data of the cross key (the operation switch  36   a  in FIG. 1). If the read operation data is the operation data of the cross key, the procedure goes to step S 105 , wherein a control of the movement of the player character a is performed based on the operation data. Specifically, a process of moving the player character upward, downward, rightward, or leftward on the game map, in accordance with an upward, downward, rightward, or leftward operation of the cross key. If the read operation data is not the operation data of the cross key, the procedure goes to step S 119 .  
         [0074]    Subsequent to step S 105 , it is determined in step S 107  whether the player character a has come to a connecting point on the ground map (for example, the dungeon-map entrance  130   a  in FIG. 3). If the player character a has come to a connecting point, the procedure goes to step S 109 , wherein a sub-map to which the player character is to move is determined with reference to the tables of FIG. 7A to move the player character a to the corresponding point on the sub-map. Subsequent to step S 109 , in step S 1 , a process of instructing the second game machine  30   a  to start processing and transmitting the type of the destination sub-map determined in step S 109  to the second game machine  30   a  is performed. If the player character a has not come to a connecting point or Subsequent to step S 11 , the procedure goes to step S 113 .  
         [0075]    In step S 113 , it is determined whether the player character a has come to a connecting point on the sub-map (for example, the ground-map entrance  230   a  in FIG. 6). If the player character a has come to a connecting point, the procedure goes to step S 115 , wherein the corresponding point on the ground map to which the player character is to move is determined with reference to the tables of FIG. 7B to move the player character a to the corresponding point is performed. Subsequent to step S 115 , in step S 117 , a process of instructing the second game machine  30   a  to end processing is performed. If the player character a has not come to a connecting point or Subsequent to step S 117 , the procedure goes to step S 119 .  
         [0076]    In step S 119 , it is determined whether the operation data read in step S 101  is the operation data of the A button (the operation switch  36   b  in FIG. 1). If the read operation data is the operation data of the α button, the procedure goes to step S 121 , wherein it is determined whether the player character a is located on the ground map. If the player character a is located on the ground map, the procedure goes to step S 123 , wherein it is determined whether any other character (any other player character or any enemy character) is located at the corresponding point on any sub-map. If it is determined that any other character is located at the corresponding point, the procedure goes to step S 125 , wherein a process of damaging that character (impairing its life, which is one of its attributes) is performed. If it is determined in step S 119  that the operation data is not the operation data of the A button, if it is determined in step S 121  that the player character a is not located on the ground map, if it is determined in step S 123  that no other character is located, or Subsequent to step S 125 , the procedure goes to step S 127 .  
         [0077]    If the player character a is located on the sub-map when the A button is operated, a process of damaging the other character located at the corresponding point on the ground map may be performed.  
         [0078]    In step S 127 , it is determined whether the process of step S 101  to S 125  has been performed on all of the second game machines  30   a  through  30   d . If any one of the second game machines has not yet been processed, the procedure returns to step S 101  for processing that unprocessed second game machine (the process is performed with x=a, then x=b, x=c, and x=d).  
         [0079]    If it is determined in step S 127  that all of the second game machines  30   a  through  30   d  have been processed, the procedure goes to step S 129  of FIG. 11, wherein a process of controlling the movement of the enemy character is performed. The movement of the enemy character is automatically controlled based on a predetermined algorithm defined in the game program. Subsequent to step S 129 , it is determined in step S 131  whether a player character x (first, a process is performed for a case where x=a, then x=b, x=c, and x=d. Hereinafter, descriptions are made for an example where x=a) is located on any sub-map. If it is determined that the player character a is located on any sub-map, the procedure goes to step S 133 , wherein a process of transmitting the location (X and Y coordinates) of the player character a on the sub-map, a location of any other player character on the same sub-map, and a location of any enemy character on the same sub-map to the second game machine  30   a  is performed.  
         [0080]    Subsequent to step S 133 , it is determined in step S 135  whether the process of steps S 131  and S 133  has been performed on all of the player characters a through d. If any of the player characters a through d has not yet been processed, the procedure returns to step S 131  for processing unprocessed player character (the process is performed with x=b, then x=c and x=d).  
         [0081]    If it is determined in step S 135  that all player characters have been processed, the procedure goes to step S 137 , wherein a process of setting the location and size of an area of the ground map to be displayed on the television monitor  60  (the display area  150  in FIG. 3) is performed. Specifically, the display area is set so as to satisfy both of the following conditions: ( 1 ) all player characters located on the ground map are displayed on the television monitor  60 , and ( 2 ) all marks corresponding to the player characters located on any sub-map (the marks  150  in FIG. 8) are displayed on the television monitor  60 . Furthermore, specifically, four corners of the display area  150  are determined based on maximum and minimum values of the X and Y coordinates of the location of the player character on the ground map and the locations on the ground map that correspond to the locations of the player characters on the sub-map.  
         [0082]    Subsequent to step S 137 , in step S 139 , a process of displaying the player character(s) on the ground map on the television monitor  60  is performed. Subsequent to step S 139 , in step S 141 , a process of transforming the location of the player character located on the sub-map to the corresponding point on the ground map and then displaying the mark  150  as illustrated in FIG. 8 on the television monitor  60  is performed.  
         [0083]    Subsequent to step S 141 , in step S 143 , an enemy character located on the ground map within the display area set in step S 137  is displayed on the television monitor  60 . Subsequent to step S 143 , in step S 145 , other objects located on the ground map within the display area set in step S 137  are displayed on the television monitor  60 . Subsequent to step S 145 , in step S 147 , the ground map within the display area set in step S 137  is displayed on the television monitor  60 . Subsequent to step S 147 , it is determined in step S 149  whether or not the game has been cleared or over. If the game has been cleared or over, the game process ends. Otherwise, the procedure returns to step S 101  of FIG. 10 for repeating the process.  
         [0084]    [0084]FIG. 12 is a flowchart showing the details of the game process performed in the above-described step S 27  of FIG. 9 by the CPU  31  of the second game machine  30 . In this game process, the CPU  31  first determines in step S 201  whether a process start instruction to be transmitted in step S 111  of FIG. 10 from the first game machine  20  has been received. If such an instruction has not yet been received, the procedure goes to step S 203 , wherein a process of transmitting the operation data (data of the operation switches  36   a  through  36   c ) to the first game machine  20  is performed. That is, until receiving a process start instruction from the first game machine  20 , the second game machine  30  merely performs the process of transmitting the operation data to the first game machine  30 .  
         [0085]    If a process start instruction has been received, on the other hand, the procedure goes to step S 205 , wherein a process of receiving the type of the sub-map transmitted in the above-described step S 111  of FIG. 10 from the first game machine  20  and then selecting that sub-map from a plurality of sub-maps (the dungeon map, the house map, and the castle map) is performed. Subsequent to step S 205 , it is determined in step S 207  whether a process end instruction to be transmitted in the above-described step S 117  of FIG. 10 from the first game machine  20  has been received. If a process end instruction has been received, the procedure goes to step S 209 , wherein a process of clearing the screen is performed. If a process end instruction has not yet been received, the procedure goes to step S 211 , wherein a process of transmitting the operation data to the first game machine  30  is performed. Subsequent to step S 211 , in step S 213 , the second game machine  30  receives the data transmitted in above-described step S 133  of FIG. 11, that is, the location of the relevant player character, a location of any other player character on the same sub-map, and a location of an enemy character on the same sub-map.  
         [0086]    Subsequent to step S 213 , in step S 215 , a certain area centering on the location of the player character on the sub-map is set as a display area (the display area  240  of FIG. 6). Subsequent to step S 215 , in step S 217 , the relevant player character is displayed on the LCD  35 . Subsequent to step S 217 , in step S 219 , any other player character, any enemy character, and other objects located on the sub-map within the display area set in step S 215  are displayed. Further, in step S 221 , the sub-map within the display area set in step S 215  is displayed. Subsequent to step S 221 , it is determined in step S 223  whether or not the game has been cleared or over. If the game has been cleared or over, the game process ends. Otherwise, the procedure returns to step S 201  of FIG. 12 for repeating the process.  
         [0087]    As has been described above, in the present embodiment, the program for the second game machine as well as the program for the first game machine is stored in the DVD  50 . Then, prior to start a game process, the program for the second game machine is transferred to the second game machine. Alternatively, the program for the second game machine can be stored in a game cartridge removably inserted in the second game machine.  
         [0088]    In the above embodiment, the movement of every player character is controlled by the first game machine  20 . Alternatively, each second game machine  30  can control the movement of every player character, and then transmit the control results to the first game machine.  
         [0089]    Still further, in the above embodiment, the game system is configured by the first game machine  20  and the second game machine  30 . Alternatively, as illustrated in FIG. 13, a controller  80  having an LCD  81  is used instead of the second game machine  30  for configuring the game system. In this case, the image displayed on the LCD  35  in the above embodiment is displayed on the LCD  81 . The image data for display on the LCD  81  is generated by the CPU  21  of the first game machine  20  executing a game program (having a function of both the program for the first game machine and the program for the second game machine in the present embodiment). The generated image data is transferred through a cable to the controller  80 .  
         [0090]    While the invention has been described in detail, the foregoing description is in all aspects illustrative and not restrictive. It is understood that numerous other modifications and variations can be devised without departing from the scope of the invention.