Abstract:
A gaming machine for conducting a wagering game includes a value input device for receiving a wager, an array of positions for displaying respective randomly selected symbols, and a controller. The displayed symbols include a special symbol and a chain of adjacent symbols at least partially encompassing the special symbol. The controller is operative to progressively move and stop the chain of adjacent symbols at each of a plurality of locations and evaluate the array for any winning combinations of the displayed symbols when the chain of adjacent symbols is stopped at each location.

Description:
CROSS-REFERENCE TO RELATED APPLICATION 
     This application is a U.S. national phase of International Application No. PCT/US2006/019997, filed May 24, 2006, which claims the benefit of priority of U.S. Provisional Patent Application No. 60/684,434, filed May 25, 2005, both of which are incorporated by reference in their entireties. 
    
    
     COPYRIGHT 
     A portion of the disclosure of this patent document contains material which is subject to copyright protection. The copyright owner has no objection to the facsimile reproduction by anyone of the patent disclosure, as it appears in the Patent and Trademark Office patent files or records, but otherwise reserves all copyright rights whatsoever. 
     FIELD OF THE INVENTION 
     The present invention relates generally to gaming machines, and methods for playing wagering games, and more particularly, to a gaming machine having a rotating wild feature. 
     BACKGROUND OF THE INVENTION 
     Gaming machines, such as slot machines, video poker machines and the like, have been a cornerstone of the gaming industry for several years. Generally, the popularity of such machines with players is dependent on the likelihood (or perceived likelihood) of winning money at the machine and the intrinsic entertainment value of the machine relative to other available gaming options. Where the available gaming options include a number of competing machines and the expectation of winning at each machine is roughly the same (or believed to be the same), players are likely to be attracted to the most entertaining and exciting machines. Shrewd operators consequently strive to employ the most entertaining and exciting machines, features, and enhancements available because such machines attract frequent play and hence increase profitability to the operator. Therefore, there is a continuing need for gaming machine manufacturers to continuously develop new games and improved gaming enhancements that will attract frequent play through enhanced entertainment value to the player. 
     One concept that has been successfully employed to enhance the entertainment value of a game is the concept of a “secondary” or “bonus” game that may be played in conjunction with a “basic” game. The bonus game may comprise any type of game, either similar to or completely different from the basic game, which is entered upon the occurrence of a selected event or outcome in the basic game. Generally, bonus games provide a greater expectation of winning than the basic game and may also be accompanied with more attractive or unusual video displays and/or audio. Bonus games may additionally award players with “progressive jackpot” awards that are funded, at least in part, by a percentage of coin-in from the gaming machine or a plurality of participating gaming machines. Because the bonus game concept offers tremendous advantages in player appeal and excitement relative to other known games, and because such games are attractive to both players and operators, there is a continuing need to develop gaming machines with new types of bonus games to satisfy the demands of players and operators. 
     SUMMARY OF THE INVENTION 
     According to one aspect of the present invention, a gaming machine for conducting a wagering game includes a value input device for receiving a wager, an array of positions for displaying respective randomly selected symbols, and a controller. The displayed symbols include a special symbol and a chain of adjacent symbols at least partially encompassing the special symbol. The controller is operative to progressively move and stop the chain of adjacent symbols at each of a plurality of locations and evaluate the array for any winning combinations of the displayed symbols when the chain of adjacent symbols is stopped at each location. 
     According to another aspect of the invention, a method of conducting a wagering game on a gaming machine comprises receiving a wager; displaying randomly selected symbols at respective positions in an array of positions, the displayed symbols including a special symbol and a chain of adjacent symbols at least partially encompassing the special symbol; progressively moving and stopping the chain of adjacent symbols at each of a plurality of locations; and evaluating the array for any winning combinations of the displayed symbols when the chain of adjacent symbols is stopped at each location 
     According to yet another aspect of the invention, a computer readable storage medium is encoded with instructions for directing a gaming device to perform the above method. 
     Additional aspects of the invention will be apparent to those of ordinary skill in the art in view of the detailed description of various embodiments, which is made with reference to the drawings, a brief description of which is provided below. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a perspective view of a gaming machine embodying the present invention; 
         FIG. 2  is a block diagram of a control system suitable for operating the gaming machine; 
         FIG. 3  is a display image associated with wagering game conducted on the gaming machine; 
         FIG. 4  depicts a series of diagrams of available paylines that are enabled according to a player&#39;s wager; 
         FIG. 5  depicts an arrangement of buttons on a button panel of the gaming machine for allowing a player to place a wager; 
         FIGS. 6 through 11  are a series of display images associated with a single rotating wild bonus of the wagering game; and 
         FIGS. 12 through 19  are a series of display images associated with a double rotating wild bonus of the wagering game. 
     
    
    
     DETAILED DESCRIPTION 
     While this invention is susceptible of embodiment in many different forms, there is shown in the drawings and will herein be described in detail preferred embodiments of the invention with the understanding that the present disclosure is to be considered as an exemplification of the principles of the invention and is not intended to limit the broad aspect of the invention to the embodiments illustrated. 
     Referring to  FIG. 1 , a gaming machine  10  is used in gaming establishments such as casinos. With regard to the present invention, the gaming machine  10  may be any type of gaming machine and may have varying structures and methods of operation. For example, the gaming machine  10  may be an electromechanical gaming machine configured to play mechanical slots, or it may be an electronic gaming machine configured to play a video casino game, such as blackjack, slots, keno, poker, blackjack, roulette, etc. 
     The gaming machine  10  comprises a housing  12  and includes input devices, including a value input device  18  and a player input device  24 . For output the gaming machine  10  includes a primary display  14  for displaying information about the basic wagering game. The primary display  14  can also display information about a bonus wagering game and a progressive wagering game. The gaming machine  10  may also include a secondary display  16  for displaying game events, game outcomes, and/or signage information. While these typical components found in the gaming machine  10  are described below, it should be understood that numerous other elements may exist and may be used in any number of combinations to create various forms of a gaming machine  10 . 
     The value input device  18  may be provided in many forms, individually or in combination, and is preferably located on the front of the housing  12 . The value input device  18  receives currency and/or credits that are inserted by a player. The value input device  18  may include a coin acceptor  20  for receiving coin currency (see  FIG. 1 ). Alternatively, or in addition, the value input device  18  may include a bill acceptor  22  for receiving paper currency. Furthermore, the value input device  18  may include a ticket reader, or barcode scanner, for reading information stored on a credit ticket, a card, or other tangible portable credit storage device. The credit ticket or card may also authorize access to a central account, which can transfer money to the gaming machine  10 . 
     The player input device  24  comprises a plurality of push buttons  26  on a button panel for operating the gaming machine  10 . In addition, or alternatively, the player input device  24  may comprise a touch screen  28  mounted by adhesive, tape, or the like over the primary display  14  and/or secondary display  16 . The touch screen  28  contains soft touch keys  30  denoted by graphics on the underlying primary display  14  and used to operate the gaming machine  10 . The touch screen  28  provides players with an alternative method of input. A player enables a desired function either by touching the touch screen  28  at an appropriate touch key  30  or by pressing an appropriate push button  26  on the button panel. The touch keys  30  may be used to implement the same functions as push buttons  26 . Alternatively, the push buttons  26  may provide inputs for one aspect of the operating the game, while the touch keys  30  may allow for input needed for another aspect of the game. 
     The various components of the gaming machine  10  may be connected directly to, or contained within, the housing  12 , as seen in  FIG. 1 , or may be located outboard of the housing  12  and connected to the housing  12  via a variety of different wired or wireless connection methods. Thus, the gaming machine  10  comprises these components whether housed in the housing  12 , or outboard of the housing  12  and connected remotely. 
     The operation of the basic wagering game is displayed to the player on the primary display  14 . The primary display  14  can also display the bonus game associated with the basic wagering game. The primary display  14  may take the form of a cathode ray tube (CRT), a high resolution LCD, a plasma display, an LED, or any other type of display suitable for use in the gaming machine  10 . As shown, the primary display  14  includes the touch screen  28  overlaying the entire monitor (or a portion thereof) to allow players to make game-related selections. Alternatively, the primary display  14  of the gaming machine  10  may include a number of mechanical reels to display the outcome in visual associated to at least one payline  32 . In the illustrated embodiment, the gaming machine  10  is an “upright” version in which the primary display  14  is oriented vertically relative to the player. Alternatively, the gaming machine may be a “slant-top” version in which the primary display  14  is slanted at about a thirty-degree angle toward the player of the gaming machine  10 . 
     A player begins play of the basic wagering game by making a wager via the value input device  18  of the gaming machine  10 . A player can select play by using the player input device  24 , via the buttons  26  or the touch screen keys  30 . The basic game consists of a plurality of symbols arranged in an array, and includes at least one payline  32  that indicates one or more outcomes of the basic game. Such outcomes are randomly selected in response to the wagering input by the player. At least one of the plurality of randomly-selected outcomes may be a start-bonus outcome, which can include any variations of symbols or symbol combinations triggering a bonus game. 
     In some embodiments, the gaming machine  10  may also include a player information reader  52  that allows for identification of a player by reading a card with information indicating his or her true identity. The player information reader  52  is shown in  FIG. 1  as a card reader, but may take on many forms including a ticket reader, bar code scanner, RFID transceiver or computer readable storage medium interface. Currently, identification is generally used by casinos for rewarding certain players with complimentary services or special offers. For example, a player may be enrolled in the gaming establishment&#39;s loyalty club and may be awarded certain complimentary services as that player collects points in his or her player-tracking account. The player inserts his or her card into the player information reader  52 , which allows the casino&#39;s computers to register that player&#39;s wagering at the gaming machine  10 . The gaming machine  10  may use the secondary display  16  or other dedicated player-tracking display for providing the player with information about his or her account or other player-specific information. Also, in some embodiments, the information reader  52  may be used to restore game assets that the player achieved and saved during a previous game session. 
     Turning now to  FIG. 2 , the various components of the gaming machine  10  are controlled by a central processing unit (CPU)  34 , also referred to herein as a controller or processor (such as a microcontroller or microprocessor). To provide gaming functions, the controller  34  executes one or more game programs stored in a computer readable storage medium, in the form of memory  36 . The controller  34  performs the random selection (using a random number generator (RNG)) of an outcome from the plurality of possible outcomes of the wagering game. Alternatively, the random event may be determined at a remote controller. The remote controller may use either an RNG or pooling scheme for its central determination of a game outcome. It should be appreciated that the controller  34  may include one or more microprocessors, including but not limited to a master processor, a slave processor, and a secondary or parallel processor. 
     The controller  34  is also coupled to the system memory  36  and a money/credit detector  38 . The system memory  36  may comprise a volatile memory (e.g., a random-access memory (RAM)) and a non-volatile memory (e.g., an EEPROM). The system memory  36  may include multiple RAM and multiple program memories. The money/credit detector  38  signals the processor that money and/or credits have been input via the value input device  18 . Preferably, these components are located within the housing  12  of the gaming machine  10 . However, as explained above, these components may be located outboard of the housing  12  and connected to the remainder of the components of the gaming machine  10  via a variety of different wired or wireless connection methods. 
     As seen in  FIG. 2 , the controller  34  is also connected to, and controls, the primary display  14 , the player input device  24 , and a payoff mechanism  40 . The payoff mechanism  40  is operable in response to instructions from the controller  34  to award a payoff to the player in response to certain winning outcomes that might occur in the basic game or the bonus game(s). The payoff may be provided in the form of points, bills, tickets, coupons, cards, etc. For example, in  FIG. 1 , the payoff mechanism  40  includes both a ticket printer  42  and a coin outlet  44 . However, any of a variety of payoff mechanisms  40  well known in the art may be implemented, including cards, coins, tickets, smartcards, cash, etc. The payoff amounts distributed by the payoff mechanism  40  are determined by one or more pay tables stored in the system memory  36 . 
     Communications between the controller  34  and both the peripheral components of the gaming machine  10  and external systems  50  occur through input/output (I/O) circuits  46 ,  48 . More specifically, the controller  34  controls and receives inputs from the peripheral components of the gaming machine  10  through the input/output circuits  46 . Further, the controller  34  communicates with the external systems  50  via the I/O circuits  48  and a communication path (e.g., serial, parallel, IR, RC, 10bT, etc.). The external systems  50  may include a gaming network, other gaming machines, a gaming server, communications hardware, or a variety of other interfaced systems or components. Although the I/O circuits  46 ,  48  may be shown as a single block, it should be appreciated that each of the I/O circuits  46 ,  48  may include a number of different types of I/O circuits. 
     Controller  34 , as used herein, comprises any combination of hardware, software, and/or firmware that may be disposed or resident inside and/or outside of the gaming machine  10  that may communicate with and/or control the transfer of data between the gaming machine  10  and a bus, another computer, processor, or device and/or a service and/or a network. The controller  34  may comprise one or more controllers or processors. In  FIG. 2 , the controller  34  in the gaming machine  10  is depicted as comprising a CPU, but the controller  34  may alternatively comprise a CPU in combination with other components, such as the I/O circuits  46 ,  48  and the system memory  36 . 
     According to an embodiment of the present invention, a gaming machine conducts a wagering game called “Wild &amp; Loose.” With respect to the “Wild &amp; Loose” game, the primary display  14  is preferably a video display.  FIG. 3  depicts a display image associated with the “Wild &amp; Loose” game. The game is implemented on a plurality of symbol-bearing reels that, in response to a wager, are rotated and stopped to place symbols at positions  60   a  through  60   n  in an array. Unless a specific position in the array is being specified, the positions  60   a  through  60   n  are referred to herein by reference numeral  60 . The “5-4-5” array of symbol positions  60  may, for example, includes three rows where the top and bottom rows each include five aligned symbol positions  60  and the middle row includes four symbol positions. The top and bottom rows are aligned relative to each other, while the middle row is horizontally offset by one-half symbol position relative to the top and bottom rows. Each position  60  may be associated with a distinct simulated reel such that the fourteen illustrated positions  60  are associated with fourteen respective reels that are spun and stopped to generate symbols at the respective positions  60 . Alternatively, a plurality of groups of multiple positions  60  may be associated with respective simulated reel, e.g. a first reel may generate symbols for the first position in each row, a second reel may generate symbols for the second position in each row, a third reel may generate symbols for the third position in each row, a fourth reel may generate symbols for the fourth position in each row, and a fifth reel may generate symbols for the fifth position in the top and bottom rows. 
     The game generates the symbols in  FIG. 3  in visual associated with a plurality of paylines.  FIG. 4  includes diagrams of the available paylines that are enabled according to a player&#39;s wager. The available paylines include paylines  1  through  20  and a Max Play Bonus Line. For ease of understanding, each payline is illustrated in a separate diagram relative to the array of symbol positions  60 . The Max Play Bonus Line covers the middle row and is free (i.e. no extra wager) when paylines  1  through  20  are enabled, but is otherwise not enabled when less than 20 lines are selected. 
     As noted above, the paylines are enabled according to a player&#39;s wager.  FIG. 5  depicts an arrangement of buttons  62  on a button panel for allowing a player to place a wager. With respect to the “Wild &amp; Loose” game, the video display  14  likewise includes on-screen icons, as shown in  FIG. 3 , which either mimic or abbreviate the ten-button panel in  FIG. 5 . The button panel arrangement includes, for example, ten buttons  62 . Using the ten-button panel, the player selects the number of paylines and credits to wager per game cycle all with the click of one button. For example, selecting the “1” button enables payline  1  and wagers 1 credit; selecting the “9” button enables paylines  1  through  9  inclusive and wagers 9 credits; selecting the “20” button enables paylines  1  through  20  inclusive and the “Max Play Bonus Line” and wagers 20 credits; and so one. Choosing any of the buttons  62  from the upper portion of the ten-button panel selects paylines and wagers credits applying to the base bet only, thereby awarding the base pay for winning combinations occurring for the selected paylines only per game cycle. For example, selecting the “9” button paylines  1  through  9  inclusive and wagers 9 credits. Therefore, a winning combination of three Elephant symbols occurring on any of the selected paylines (i.e.  1  through  9  inclusive) awards 10 credits, which is the inherent award for that symbol combination. Choosing any of the buttons  62  from the lower portion of the ten-button panel selects paylines and wagers credits that apply to both the base bet and the bonus bet. Additionally, multipliers that range from 1 times (1×) to 10 times (10×) the wager are set for potential winning combinations applying to both the base and bonus bet. For example, selecting the “50” button enables all the available paylines (i.e.  1  through  20  inclusive plus the “Max Play Bonus Line”) and wagers 50 credits. The wager is broken down as follows: 20 credits with a multiplier of 2 times (2×) applies towards the base bet and 5 credits with a multiplier of 2 times (2×) applied towards the bonus bet. Selecting the “75” button enables all the available paylines and wagers 75 credits. The wager is broken down as follows: 20 credits with a multiplier of 3 times (3×) applied towards the base bet and 5 credits with a multiplier of 3 times (3×) applied towards the bonus bet. 
     Referring to  FIG. 6 , a Rotating Wild Monkey symbol  64  in position  60   g  or position  62   h  (see  FIG. 3  for specified positions  60   a  through  60   n ) triggers a single Rotating Wild bonus in which the surrounding symbol positions and their occupying symbols link with the Rotating Wild Monkey symbol  64  and rotate as one cohesive chain in a circular, clockwise pattern creating new potential awards. In one embodiment, all paylines must be enabled to qualify for the Rotating Wild bonus. In the illustrated example, a Rotating Wild Monkey symbol  64  appears in position  60   g  and, as a result, positions  60   b ,  60   c ,  60   f ,  60   h ,  60   k , and  60   l  and their occupying symbols link with the Rotating Wild Monkey symbol  64  and rotate as one cohesive chain in a circular, clockwise pattern creating new potential awards. 
     Starting from the initial position in  FIG. 6 , the rotating chain progressively rotates to and stops at each of five different rotational positions shown in  FIGS. 7 through 11  and then returns to the original position in  FIG. 6 . At each stopping position, the symbols in the symbol array are evaluated according to the pay table for any line pays (i.e. winning combinations of line paying symbols along enabled paylines) and scatter pays (i.e. winning combinations of scatter paying symbols in the symbol array, whether or not the symbols appear on an enabled payline). The player is awarded for all such line and scatter pays. The awards generated at the respective rotational positions accrue on a “paid” meter  66  (see  FIG. 3 ) on the display and, at the conclusion of the Rotating Wild bonus, are transferred from the “paid” meter  66  to a “credits” meter  68  (see  FIG. 3 ). 
     Referring to  FIG. 12 , Rotating Wild Monkey symbols  64  in positions  60   g  and  62   h  (see  FIG. 3  for specified positions  60   a  through  60   n ) trigger a Double Rotating Wild bonus in which the surrounding symbol positions  60   b ,  60   c ,  60   d ,  60   f ,  60   i ,  60   k ,  60   l , and  60   m  and their occupying symbols link with the Rotating Wild Monkey symbols  64  and rotate as one cohesive chain in an elliptical, clockwise pattern creating new potential awards. In one embodiment, all paylines must be enabled to qualify for the Double Rotating Wild bonus. 
     Starting from the initial position in  FIG. 12 , the rotating chain progressively rotates to and stops at each of seven different rotational positions shown in  FIGS. 13 through 19  and then returns to the original position in  FIG. 12 . At each stopping position, the symbols in the symbol array are evaluated according to the pay table for any line pays (i.e. winning combinations of line paying symbols along enabled paylines) and scatter pays (i.e. winning combinations of scatter paying symbols in the symbol array, whether or not the symbols appear on an enabled payline). The player is awarded for all such line and scatter pays. The awards generated at the respective rotational positions accrue on a “paid” meter  66  (see  FIG. 3 ) on the display and, at the conclusion of the Double Rotating Wild bonus, are transferred from the “paid” meter  66  to a “credits” meter  68  (see  FIG. 3 ). 
     If each position  60  of the symbol array is associated with a distinct simulated reel, the Rotating Wild bonus causes the reels surrounding the triggering Rotating Wild Monkey symbol(s)  64  to progressively move to and stop at each of the rotational positions shown in the figures. 
     In an alternative embodiment, the “5-4-5” symbol array is replaced with a more conventional array of aligned rows and columns such as a 3×5 array having three rows and five columns. A rotating wild symbol in one of the three interior positions of a 3×5 array may trigger a rotating wild bonus in which the surrounding symbols/positions rotate to and stop at each of seven rotational positions and then return to the original, starting position. A rotating wild symbol in all three of the three interior positions of a 3×5 array may trigger a triple rotating wild bonus in which the surrounding symbols/positions rotate to and stop at each of eleven rotational positions and then return to the original, starting position. A rotating wild symbol in the single interior position of a 3×3 array may trigger a rotating wild bonus in which the surrounding symbols/positions rotate to and stop at each of seven rotational positions and then return to the original, starting position. 
     In another embodiment, a rotating wild bonus may be triggered by a rotating wild symbol in a peripheral position of the array. In this case, a symbol at position  60   j , for example, would rotate to position  60   a  if these positions are part of the rotating chain. Likewise, a symbol at position  60   e  would rotate to position  60   n  if these positions are part of the rotating chain. Alternatively, upon triggering the rotating wild bonus, a random symbol may appear outside the array, e.g. at a position to the left of position  60   f , and become part of the rotating chain to fill in any gaps that would otherwise exist in the chain. 
     In another embodiment, the symbol for triggering the rotating bonus need not be wild or may alternatively be transformed to a wild upon triggering the bonus. 
     In another embodiment, the rotating bonus may be triggered by a symbol or event occurring outside the symbol array such that the bonus is triggered independent from the symbols appearing in the array. 
     In another embodiment, the chain of symbols/positions in the bonus may move along a closed loop path or non-closed path that is neither circular nor elliptical. 
     Each of these embodiments and obvious variations thereof is contemplated as falling within the spirit and scope of the claimed invention, which is set forth in the following claims.