Patent Publication Number: US-11043073-B2

Title: Symbol interchange method, gaming machine, and computer readable media

Description:
RELATED APPLICATIONS 
     This application is a continuation of U.S. patent application Ser. No. 15/670,393 having a filing date of Aug. 7, 2017, which is a continuation of U.S. patent application Ser. No. 13/114,621 having a filing date of May 24, 2011, which claims priority to U.S. Provisional Application No. 61/348,087 having a filing date of May 25, 2010, all of which are hereby incorporated herein by reference in their entirety. 
    
    
     BACKGROUND OF THE INVENTION 
     The present invention relates to a method of gaming, a gaming system, and a game controller. 
     In many gaming venues, gaming systems are provided in the form of gaming machines. A popular game available on such gaming machines is a spinning-reel type game. In a 5×3 spinning-reel type game, five reels are displayed to a player, each of the reels corresponding to a column of three display positions. Typically, a player initiates a play of the game by placing a wager and causing all the reels to spin. When the spinning reels stop, they reveal a symbol for each display position of each reel, and an award is provided to the player if the displayed symbols comprise a winning symbol combination. 
     While such gaming systems provide players with enjoyment, a need exists for alternative gaming systems in order to maintain or increase player enjoyment. 
     BRIEF SUMMARY OF THE INVENTION 
     In a first aspect, the invention provides an electronic method of gaming comprising: 
     selecting a symbol for display at each display position of a plurality of sets of display positions; 
     modifying the displayed symbols by interchanging a first set of symbols displayed at a first set of display positions with a second set of symbols displayed at a second set of display positions; and 
     determining whether to make an award based on the symbols displayed at the plurality of sets of display positions as modified. 
     In an embodiment, each set of display positions comprises a column of display positions. 
     In an embodiment, the method further comprises determining whether to make another award based on the symbols displayed at the plurality of sets of display positions prior to modifying the displayed symbols. 
     In an embodiment, the method further comprises determining whether a modification condition is met and modifying the displayed symbols upon the modification condition being met. 
     In an embodiment, the modification condition is that an award is to be made. 
     In an embodiment, the modification condition is that an award is not to be made. 
     In an embodiment, the modification condition is that an ante bet has been made. 
     In an embodiment, the determination of whether the modification condition is met is performed randomly. 
     In an embodiment, after it has been determined that awards may be made both before and after modification, the method further comprises displaying an option to select either the award determined before modification or the award determined after modification. 
     In an embodiment, modifying the displayed symbols further comprises interchanging a third set of symbols displayed at a third set of display positions with a fourth set of symbols displayed at a fourth set of display positions. 
     In an embodiment, the method further comprises: conducting a further round of symbol modification involving two different sets of symbols displayed at two different sets of display positions; and 
     determining whether to make an award based on the symbols displayed at the plurality of sets of display positions as twice modified. 
     In an embodiment, the method further comprises selecting one of the plurality of sets of display positions to be the first set of display positions and another one of the plurality of sets of display positions to be the second set of display positions. 
     In an embodiment, the first set of display positions and the second set of display positions are selected randomly. 
     In an embodiment, the modification of symbols comprises displaying symbols displayed at different display positions swapping with one another. 
     In an embodiment, the modification of symbols comprises displaying symbols hopping from one display position to another display position. 
     In an embodiment, the modification of symbols comprises displaying symbols sliding from one display position to another display position. 
     In an embodiment, the modification of symbols comprises displaying symbols flipping from one symbol to another symbol. 
     In a second aspect, the invention provides a gaming system comprising: 
     a display; 
     a symbol selector arranged to select a symbol for display at each display position of a plurality of sets of display positions on the display; 
     a display modifier arranged to modify the displayed symbols by interchanging a first set of symbols displayed at a first set of display positions with a second set of symbols displayed at a second set of display positions; and 
     an award determiner arranged to determine whether to make an award based on the symbols displayed at the plurality of sets of display positions as modified. 
     In an embodiment, each set of display positions is displayed as a column of display positions on the display. 
     In an embodiment, the award determiner is arranged to determine whether to make an award based on the symbols displayed at the plurality of sets of display positions prior to modification of the displayed symbols. 
     In an embodiment, the display modifier comprises a modification condition determiner arranged to determine whether a modification condition is met and the display modifier is arranged to modify the displayed symbols upon the modification condition being met. 
     In an embodiment, the modification condition is that an award is to be made. 
     In an embodiment, the modification condition is that an award is not to be made. 
     In an embodiment, the modification condition is that an ante bet has been made. 
     In an embodiment, the display modifier is arranged to randomly determine whether the modification condition is met. 
     In an embodiment, after the award determiner has determined that awards may be made both before and after modification, an option to select either the award determined before modification or the award determined after modification is displayed on the display. 
     In an embodiment, the display modifier is arranged to further modify the displayed symbols by interchanging a third set of symbols displayed at a third set of display positions with a fourth set of symbols displayed at a fourth set of display positions. 
     In an embodiment, the display modifier is arranged to conduct a further round of symbol modification involving two different sets of symbols displayed at two different sets of display positions, and wherein the award determiner is arranged to determine whether to make an award based on the symbols displayed at the plurality of sets of display positions as twice modified. 
     In an embodiment, the display modifier comprises a display position selector arranged to select one of the plurality of sets of display positions to be the first set of display positions and another one of the plurality of sets of display positions to be the second set of display positions. 
     In an embodiment, the display position selector is arranged to select the first set of display positions and the second set of display positions randomly. 
     In an embodiment, the modification of symbols comprises displaying symbols displayed at different display positions swapping with one another on the display. 
     In an embodiment, the modification of symbols comprises displaying symbols hopping from one display position to another display position on the display. 
     In an embodiment, the modification of symbols comprises displaying symbols sliding from one display position to another display position on the display. 
     In an embodiment, the modification of symbols comprises displaying symbols flipping from one symbol to another symbol on the display. 
     In a third aspect, the invention provides a game controller for a gaming system, the game controller configured to: 
     select a symbol for display at each display position of a plurality of sets of display positions on a display; 
     modify the displayed symbols by interchanging a first set of symbols displayed at a first set of display positions with a second set of symbols displayed at a second set of display positions; and 
     determine whether to make an award based on the symbols displayed at the plurality of sets of display positions as modified. 
     In an embodiment, each set of display positions comprises a column of display positions. 
     In an embodiment, the game controller is configured to determine whether to make another award based on the symbols displayed at the plurality of sets of display positions prior to modifying the displayed symbols. 
     In an embodiment, the game controller is configured to determine whether a modification condition is met and to modify the displayed symbols upon the modification condition being met. 
     In an embodiment, the modification condition is that an award is to be made. 
     In an embodiment, the modification condition is that an award is not to be made. 
     In an embodiment, the modification condition is that an ante bet has been made. 
     In an embodiment, the determination of whether the modification condition is met is performed randomly. 
     In an embodiment, the game controller is configured to, after it has been determined that awards may be made both before and after modification, display an option to select either the award determined before modification or the award determined after modification. 
     In an embodiment, modifying the displayed symbols further comprises interchanging a third set of symbols displayed at a third set of display positions with a fourth set of symbols displayed at a fourth set of display positions. 
     In an embodiment, the game controller is configured to: 
     conduct a further round of symbol modification involving two different sets of symbols displayed at two different sets of display positions; and 
     determine whether to make an award based on the symbols displayed at the plurality of sets of display positions as twice modified. 
     In an embodiment, the game controller is configured to select one of the plurality of sets of display positions to be the first set of display positions and another one of the plurality of sets of display positions to be the second set of display positions. 
     In an embodiment, the first set of display positions and the second set of display positions are selected randomly. 
     In an embodiment, the modification of symbols comprises displaying symbols displayed at different display positions swapping with one another. 
     In an embodiment, the modification of symbols comprises displaying symbols hopping from one display position to another display position. 
     In an embodiment, the modification of symbols comprises displaying symbols sliding from one display position to another display position. 
     In an embodiment, the modification of symbols comprises displaying symbols flipping from one symbol to another symbol. 
     In a fourth aspect, the invention provides a gaming machine comprising:
         a display; and   a game controller comprising:
           a symbol selector arranged to select a symbol for display at each display position of a plurality of sets of display positions on the display;   a display modifier arranged to modify the displayed symbols by interchanging a first set of symbols displayed at a first set of display positions with a second set of symbols displayed at a second set of display positions; and   an award determiner arranged to determine whether to make an award based on the symbols displayed at the plurality of sets of display positions as modified.   
               

     In an embodiment, each set of display positions comprises a column of display positions. 
     In an embodiment, the game controller is configured to determine whether to make another award based on the symbols displayed at the plurality of sets of display positions prior to modifying the displayed symbols. 
     In an embodiment, the game controller is configured to determine whether a modification condition is met and to modify the displayed symbols upon the modification condition being met. 
     In an embodiment, the modification condition is that an award is to be made. 
     In an embodiment, the modification condition is that an award is not to be made. 
     In an embodiment, the modification condition is that an ante bet has been made. 
     In an embodiment, the determination of whether the modification condition is met is performed randomly. 
     In an embodiment, the game controller is configured to, after it has been determined that awards may be made both before and after modification, display an option to select either the award determined before modification or the award determined after modification. 
     In an embodiment, modifying the displayed symbols further comprises interchanging a third set of symbols displayed at a third set of display positions with a fourth set of symbols displayed at a fourth set of display positions. 
     In an embodiment, the game controller is configured to: 
     conduct a further round of symbol modification involving two different sets of symbols displayed at two different sets of display positions; and 
     determine whether to make an award based on the symbols displayed at the plurality of sets of display positions as twice modified. 
     In an embodiment, the game controller is configured to select one of the plurality of sets of display positions to be the first set of display positions and another one of the plurality of sets of display positions to be the second set of display positions. 
     In an embodiment, the first set of display positions and the second set of display positions are selected randomly. 
     In an embodiment, the modification of symbols comprises displaying symbols displayed at different display positions swapping with one another. 
     In an embodiment, the modification of symbols comprises displaying symbols hopping from one display position to another display position. 
     In an embodiment, the modification of symbols comprises displaying symbols sliding from one display position to another display position. 
     In an embodiment, the modification of symbols comprises displaying symbols flipping from one symbol to another symbol. 
     In a fifth aspect, the invention provides computer program code which when executed implements the above electronic method. 
     In a sixth aspect, the invention provides a tangible computer readable medium comprising the above program code. 
     In a seventh aspect, the invention provides a data signal comprising the above program code. 
     In an eighth aspect, the invention extends to transmitting the above program code. 
    
    
     
       BRIEF DESCRIPTION OF SEVERAL VIEWS OF THE DRAWINGS 
       An exemplary embodiment of the invention will now be described with reference to the accompanying drawings in which: 
         FIG. 1  is a block diagram of the core components of a gaming system; 
         FIG. 2  is a perspective view of a stand alone gaming machine; 
         FIG. 3  is a block diagram of the functional components of a gaming machine; 
         FIG. 4  is a schematic diagram of the functional components of a memory; 
         FIG. 5  is a schematic diagram of a network gaming system; 
         FIG. 6  is a further block diagram of a gaming system; 
         FIG. 7  is a flow chart of an embodiment; and 
         FIGS. 8A and 8B  are diagrammatic representations of an example of a game. 
     
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     Referring to the drawings, there is shown a gaming system arranged to implement a game wherein a plurality of symbols are selected and displayed at a plurality of sets of display positions. During game play, the displayed symbols are modified by interchanging a first set of symbols displayed at a first set of display positions with a second set of symbols displayed at a second set of display positions. 
     Advantageously, the gaming system provides an alternative or additional opportunity to win. 
     General Construction of Gaming System 
     The gaming system can take a number of different forms. In a first form, a stand alone gaming machine is provided wherein all or most components required for implementing the game are present in a player operable gaming machine. 
     In a second form, a distributed architecture is provided wherein some of the components required for implementing the game are present in a player operable gaming machine and some of the components required for implementing the game are located remotely relative to the gaming machine. For example, a “thick client” architecture may be used wherein part of the game is executed on a player operable gaming machine and part of the game is executed remotely, such as by a gaming server; or a “thin client” architecture may be used wherein most of the game is executed remotely such as by a gaming server and a player operable gaming machine is used only to display audible and/or visible gaming information to the player and receive gaming inputs from the player. 
     However, it will be understood that other arrangements are envisaged. For example, an architecture may be provided wherein a gaming machine is networked to a gaming server and the respective functions of the gaming machine and the gaming server are selectively modifiable. For example, the gaming system may operate in stand alone gaming machine mode, “thick client” mode or “thin client” mode depending on the game being played, operating conditions, and so on. Other variations will be apparent to persons skilled in the art. 
     Irrespective of the form, the gaming system has several core components. At the broadest level, the core components are a player interface  50  and a game controller  60  as illustrated in  FIG. 1 . The player interface is arranged to enable manual interaction between a player and the gaming system and for this purpose includes the input/output components required for the player to enter instructions to play the game and observe the game outcomes. 
     Components of the player interface may vary from embodiment to embodiment but will typically include a credit mechanism  52  to enable a player to input credits and receive payouts, one or more displays  54 , a game play mechanism  56  including one or more input devices that enable a player to input game play instructions (e.g. to place a wager), and one or more speakers  58 . 
     The game controller  60  is in data communication with the player interface and typically includes a processor  62  that processes the game play instructions in accordance with game play rules and outputs game play outcomes to the display. Typically, the game play rules are stored as program code in a memory  64  but can also be hardwired. Herein the term “processor” is used to refer generically to any device that can process game play instructions in accordance with game play rules and may include: a microprocessor, microcontroller, programmable logic device or other computational device, a general purpose computer (e.g. a PC) or a server. That is a processor may be provided by any suitable logic circuitry for receiving inputs, processing them in accordance with instructions stored in memory and generating outputs (for example on the display). Such processors are sometimes also referred to as central processing units (CPUs). Most processors are general purpose units, however, it is also know to provide a specific purpose processor using an application specific integrated circuit (ASIC) or a field programmable gate array (FPGA). 
     A gaming system in the form of a stand alone gaming machine  10  is illustrated in  FIG. 2 . The gaming machine  10  includes a console  12  having a display  14  on which are displayed representations of a game  16  that can be played by a player. A mid-trim  20  of the gaming machine  10  houses a bank of buttons  22  for enabling a player to interact with the gaming machine, in particular during game play. The mid-trim  20  also houses a credit input mechanism  24  which in this example includes a coin input chute  24 A and a bill collector  24 B. Other credit input mechanisms may also be employed, for example, a card reader for reading a smart card, debit card or credit card. Other gaming machines may configure for ticket in such that they have a ticket reader for reading tickets having a value and crediting the player based on the face value of the ticker. A player marketing module (not shown) having a reading device may also be provided for the purpose of reading a player tracking device, for example as part of a loyalty program. The player tracking device may be in the form of a card, flash drive or any other portable storage medium capable of being read by the reading device. In some embodiments, the player marketing module may provide an additional credit mechanism, either by transferring credits to the gaming machine from credits stored on the player tracking device or by transferring credits from a player account in data communication with the player marketing module. 
     A top box  26  may carry artwork  28 , including for example pay tables and details of bonus awards and other information or images relating to the game. Further artwork and/or information may be provided on a front panel  29  of the console  12 . A coin tray  30  is mounted beneath the front panel  29  for dispensing cash payouts from the gaming machine  10 . 
     The display  14  shown in  FIG. 2  is in the form of a video display unit, particularly a cathode ray tube screen device. Alternatively, the display  14  may be a liquid crystal display, plasma screen, any other suitable video display unit, or the visible portion of an electromechanical device. The top box  26  may also include a display, for example a video display unit, which may be of the same type as the display  14 , or of a different type. 
       FIG. 3  shows a block diagram of operative components of a typical gaming machine which may be the same as or different to the gaming machine of  FIG. 2 . 
     The gaming machine  100  includes a game controller  101  having a processor  102  mounted on a circuit board. Instructions and data to control operation of the processor  102  are stored in a memory  103 , which is in data communication with the processor  102 . Typically, the gaming machine  100  will include both volatile and non-volatile memory and more than one of each type of memory, with such memories being collectively represented by the memory  103 . 
     The gaming machine has hardware meters  104  for purposes including ensuring regulatory compliance and monitoring player credit, an input/output (I/O) interface  105  for communicating with peripheral devices of the gaming machine  100 . The input/output interface  105  and/or the peripheral devices may be intelligent devices with their own memory for storing associated instructions and data for use with the input/output interface or the peripheral devices. A random number generator module  113  generates random numbers for use by the processor  102 . Persons skilled in the art will appreciate that the reference to random numbers includes pseudo-random numbers. 
     In the example shown in  FIG. 3 , a player interface  120  includes peripheral devices that communicate with the game controller  101  including one or more displays  106 , a touch screen and/or buttons  107  (which provide a game play mechanism), a card and/or ticket reader  108 , a printer  109 , a bill acceptor and/or coin input mechanism  110  and a coin output mechanism  111 . Additional hardware may be included as part of the gaming machine  100 , or hardware may be omitted as required for the specific implementation. For example, while buttons or touch screens are typically used in gaming machines to allow a player to place a wager and initiate a play of a game any input device that enables the player to input game play instructions may be used. For example, in some gaming machines a mechanical handle is used to initiate a play of the game. 
     In addition, the gaming machine  100  may include a communications interface, for example a network card  112 . The network card may, for example, send status information, accounting information or other information to a bonus controller, central controller, server or database and receive data or commands from the bonus controller, central controller, server or database. In embodiments employing a player marketing module, communications over a network may be via player marketing module—i.e. the player marketing module may be in data communication with one or more of the above devices and communicate with it on behalf of the gaming machine. 
       FIG. 4  shows a block diagram of the main components of an exemplary memory  103 . The memory  103  includes RAM  103 A, EPROM  103 B and a mass storage device  103 C. The RAM  103 A typically temporarily holds program files for execution by the processor  102  and related data. The EPROM  1038  may be a boot ROM device and/or may contain some system or game related code. The mass storage device  103 C is typically used to store game programs, the integrity of which may be verified and/or authenticated by the processor  102  using protected code from the EPROM  103 B or elsewhere. 
     It is also possible for the operative components of the gaming machine  100  to be distributed, for example input/output devices  106 , 107 , 108 , 109 , 110 , 111  to be provided remotely from the game controller  101 . 
       FIG. 5  shows a gaming system  200  in accordance with an alternative embodiment. The gaming system  200  includes a network  201 , which for example may be an Ethernet network. Gaming machines  202 , shown arranged in three banks  203  of two gaming machines  202  in  FIG. 5 , are connected to the network  201 . The gaming machines  202  provide a player operable interface and may be the same as the gaming machines  10 , 100  shown in  FIGS. 2 and 3 , or may have simplified functionality depending on the requirements for implementing game play. While banks  203  of two gaming machines are illustrated in  FIG. 5 , banks of one, three or more gaming machines are also envisaged. 
     One or more displays  204  may also be connected to the network  201 . For example, the displays  204  may be associated with one or more banks  203  of gaming machines. The displays  204  may be used to display representations associated with game play on the gaming machines  202 , and/or used to display other representations, for example promotional or informational material. 
     In a thick client embodiment, game server  205  implements part of the game played by a player using a gaming machine  202  and the gaming machine  202  implements part of the game. With this embodiment, as both the game server and the gaming device implement part of the game, they collectively provide a game controller. A database management server  206  may manage storage of game programs and associated data for downloading or access by the gaming devices  202  in a database  206 A. Typically, if the gaming system enables players to participate in a Jackpot game, a Jackpot server  207  will be provided to perform accounting functions for the Jackpot game. A loyalty program server  212  may also be provided. 
     In a thin client embodiment, game server  205  implements most or all of the game played by a player using a gaming machine  202  and the gaming machine  202  essentially provides only the player interface. With this embodiment, the game server  205  provides the game controller. The gaming machine will receive player instructions, pass these to the game server which will process them and return game play outcomes to the gaming machine for display. In a thin client embodiment, the gaming machines could be computer terminals, e.g. PCs running software that provides a player interface operable using standard computer input and output components. Other client/server configurations are possible, and further details of a client/server architecture can be found in WO 2006/052213 and PCT/SE2006/000559, the disclosures of which are incorporated herein by reference. 
     Servers are also typically provided to assist in the administration of the gaming network  200 , including for example a gaming floor management server  208 , and a licensing server  209  to monitor the use of licenses relating to particular games. An administrator terminal  210  is provided to allow an administrator to run the network  201  and the devices connected to the network. 
     The gaming system  200  may communicate with other gaming systems, other local networks, for example a corporate network, and/or a wide area network such as the Internet, for example through a firewall  211 . 
     Persons skilled in the art will appreciate that in accordance with known techniques, functionality at the server side of the network may be distributed over a plurality of different computers. For example, elements may be run as a single “engine” on one server or a separate server may be provided. For example, the game server  205  could run a random generator engine. Alternatively, a separate random number generator server could be provided. Further, persons skilled in the art will appreciate that a plurality of game servers could be provided to run different games or a single game server may run a plurality of different games as required by the terminals. 
     Further Detail of Gaming System 
       FIG. 6  shows the functional components of an example of the gaming system. As shown in the figure, a game controller  60  comprising a processor  62  is arranged to implement a number of modules based on program code and data stored in memory  64  so as to implement a game where a plurality of symbols are selected and displayed at a plurality of sets of display positions, and where during game play, the displayed symbols are modified by interchanging a first set of symbols displayed at a first set of display positions with a second set of symbols displayed at a second set of display positions. 
     Persons skilled in the art will appreciate that the modules are typically implemented using a processor based on program code and data stored in memory but that one or more of the modules could alternatively be implemented in some other way, for example by a dedicated circuit. 
     In this example, the game is a spinning-reel type game comprising a number of columns of display positions corresponding to respective ones of a plurality of reels. Persons skilled in the art will appreciate that such a spinning-reel type game may vary in terms of the number of columns or the number of display positions per column. For example, the game may be a 4×6 spinning-reel type game comprising four columns, each column having 6 vertically adjacent display positions; a 5×3 spinning-reel type game comprising five columns, each column having 3 vertically adjacent display positions etc. 
     It is envisaged that the spinning-reel type game can be a line-based game or a reel-based game. In a line-based game, a player&#39;s win entitlement is based on how many win lines the player plays in each game (for example, a minimum of one win line up to the maximum number of win lines allowed by the game) and how much they wager per line. Such win lines are typically formed by a combination of symbol display positions, one from each reel, the symbol display positions being located relative to one another such that they form a line. Persons skilled in the art will appreciate that in some line-based games, the player&#39;s win entitlement may not be strictly limited to the lines they have selected, for example, “scatter” pays can be awarded independently of a player&#39;s selection of pay lines and can be an inherent part of a win entitlement. 
     In a reel-based game, a player obtains a win entitlement by selecting a number of reels to play and an amount to wager per reel. Such games are marketed under the trade name “Reel Power” by Aristocrat Leisure Industries Pty Ltd. The selection of the reel means that each displayed symbol of the reel can be substituted for a symbol at one or more designated display positions. In other words, all symbols displayed at symbol display positions corresponding to a selected reel can be used to form symbol combinations with symbols displayed at a designated, symbol display positions of the other reels. For example, if there are five reels and three symbol display positions for each reel such that the symbol display positions comprise three rows of five symbol display positions, the symbols displayed in the centre row are used for non-selected reels. As a result, the total number of ways to win is determined by multiplying the number of active display positions of each reels, the active display positions being all display positions of each selected reel and the designated display position of the non-selected reels. Thus, for a 5×3 spinning-reel type game having five reels and fifteen display positions, there can be 243 ways to win. 
     In  FIG. 6 , the gaming system comprises a player interface  50  having a display  54  arranged to display to a player a symbol in each of a plurality of sets of display positions of the game. In the embodiment, each set of display positions corresponds to one of the reels. For example, on a 5×3 spinning-reel type game, a set of display positions can be the 3 vertically adjacent symbols of a reel etc. 
     In this embodiment, the game controller  60  also includes memory  64  comprising game code  646  for implementing the modules. Memory  64  also includes, for use by the modules, symbol data  642 , display data  644  and award data  648 . The symbol data  642  comprises a plurality of symbols that may be selected for display on display  54  during a game. The display data  644  comprises one or more predetermined sets of display positions that may be selected during a game. The award data  648  comprises a plurality of awards that may be made. 
     Examples of awards include monetary prizes, bonus credits, feature games etc. Types of feature games include: those where a series of free game events are awarded such as free games or re-spins (where some reels are held while others are re-spun); games where the symbols on the reel are changed; and “second screen” games where game play is totally different to the base game, for example where the player makes selections in a “pick a box type” game. 
     The modules implemented by the processor  62  include a Random Number Generator (RNG)  622  and a display controller  629 . The Random Number Generator (RNG)  622  is arranged to generate random numbers (including pseudo-random numbers) for use by the other modules. Persons skilled in the art will appreciate that the RNG  622  may in another example be implemented in a separate device, for example, in a Random Number Generator server. The display controller  629  is arranged to communicate with the player interface  50  to control the display  54  of the player interface  50 . 
     In addition to the display controller  629  and the RNG  622 , the modules implemented by the processor  62  include a symbol selector  623 , a display modifier  624  and an award determiner  628 . 
     The symbol selector  623  is arranged to select a symbol for display on display  54  at each of the display positions of the game. In this embodiment, the symbol selector  623  is arranged to select each symbol from symbol data  642  stored in memory  642 . The manner in which the symbol selector  623  selects a symbol may be carried out in a variety of ways. For example, the symbol data  642  can specify a sequence of symbols for each reel such that the symbol selector  623  can select all of the symbols of a reel by selecting a stopping position in the sequence. In one example, three symbols of each of five reels may be displayed such that symbols are selected for display at fifteen display positions on display  54 . It is known to use a probability table stored in memory  64  to vary the odds of a particular stop position being selected. 
     The display modifier  624  is arranged to modify the displayed symbols by interchanging one or more sets of the symbols displayed in the plurality of display positions with another one or more sets of the symbols displayed in the plurality of display positions. For example, on a 5×3 spinning-reel type game, the display modifier  624  can modify the displayed symbols of two reels by interchanging the symbols of the left-most reel with the symbols of the middle reel. In another example, the display modifier  624  can modify four reels of displayed symbols by interchanging the symbols of the left-most reel with the symbols of the middle reel and the symbols of the right-most reel with the symbols of the second-left-most reel. In some embodiments, the display modifier  624  may modify the displayed symbols more than once. For example, after the display modifier  624  has performed a first round of modification, the display modifier  624  can perform a second round of modification to modify the displayed symbols again by interchanging a further one or more sets of symbols displayed in the plurality of display positions with another further one or more sets of symbols displayed in the plurality of display positions as modified. 
     In the embodiment, the display modifier  625  is arranged to modify the displayed symbols using a display position selector  625  and a modification condition determiner  626 . 
     The modification condition determiner  626  is arranged to determine whether a modification condition is met. The display modifier  694  is arranged to modify the displayed symbols upon the modification condition being met. The modification condition can be based on one or more game conditions or can be random. Examples of a modification condition based on game conditions include: whether an ante bet has been made by a player, whether an award is to be made to a player based on the symbols displayed on the plurality of display positions prior to modification of the displayed symbols, whether no award is made to a player based on the symbols displayed on the plurality of display positions prior to modification of the displayed symbols, whether a certain sized wager has been made by a player, whether a player has selected all the win lines of a game, whether a player has played sufficient games, whether a player is a member of a loyalty program etc. In other embodiments, the modification condition determiner  626  determines whether a modification is met randomly (for example, based on random numbers or pseudo random numbers generated by the RNG  622 ). 
     The display position selector  625  is arranged to select, from the plurality of display positions of the game, sets of display positions to be modified. Depending on the implementation, the display position selector  625  can select the sets of display positions either based on predetermined display data  644  stored in memory  64  or randomly based on random numbers or pseudo random numbers generated by the RNG  622 . 
     In the embodiment, the award determiner  628  is arranged to determine whether to make an award based on the symbols displayed at the plurality of sets of display positions prior to the display modifier  624  modifying the displayed symbols selected by the symbol selector  623 . In addition, the award determiner  623  is arranged to determine whether to make an award based on the symbols displayed at the plurality of sets of display positions as modified. The award determiner  623  is also arranged to determine whether to make an award based on the symbols displayed at the plurality of sets of display positions as further modified. For example, the award determiner  628  may make an award to a player incrementally, each time after the displayed symbols have been modified. The award determiner  628  determines whether the displayed symbols include on a selected win line (or at symbol positions covered by reel selections) a winning combination. Possible winning combinations are stored as a pay table in the award data  648 . 
     As stated previously, the display controller  629  is arranged to control the display  54 . The display controller  629  is arranged to control the display  54  based on communication from the symbol selector  623 , the display modifier  624  and/or the award determiner  628 . For example, the display controller  629  can control the display  54  to: display the symbols selected by the symbol selector  623  in the plurality of display positions, display the symbols as modified by the display modifier  624 , display that an award is to be made based on a determination by the award determiner  628 , display an option to allow a player to use an input device (such as the game play mechanism  56 ) of the player interface  50  to select either an award determined before modification of symbols or an award determined after modification of symbols if the award determiner  623  has determined that awards may be made both before and after modification of symbols etc. 
     It is envisaged that the display controller  629  can control the display  54  to display the modification of symbols in a variety of ways including: displaying symbols displayed at different display positions swapping with one another on the display  54 , displaying symbols hopping from one display position to another display position on the display  54 , displaying symbols sliding from one display position to another display position on the display  54 , displaying symbols flipping from one symbol to another symbol on the display  54 , displaying symbols shifting from one display position to another display position, displaying columns rearranging with each other, displaying symbols being transported from one display position to another display position etc. 
     It is envisaged that the display  54  is a video display and that the reels of display positions are displayed as virtual reels on the video display. However, persons skilled in the art will appreciate that the display  54  can also be implemented using mechanical or electro-mechanical reels. For example, a reel on a mechanical display can be mechanically rotated from its position to the position of another reel, provided the reels are configured such that the same symbols can be displayed. 
     It is also envisaged that animation can be used to highlight the modification of displayed symbols (for example, peripheral lights on a gaming machine may flash when the reels are being interchanged during game play) and that information can be shown to explain the modification of displayed symbols (for example, before a game starts). 
       FIG. 7  is a flowchart illustrating an embodiment of the method of gaming. At step  700 , a new spinning-reel type game is started by a player using the game play mechanism  56 . At step  710 , the symbol selector  623  selects a symbol for display at each display position of the plurality of columns or reels of display positions displayed on the display  54 . At step  720 , the selected symbols are displayed on the display  54  at each display position of the plurality of columns or reels of display positions. At step  730 , the award determiner  628  determines whether to make an award based on the displayed symbols. 
     In this embodiment, some of the displayed symbols are then selected by the display position selector  625  for modification by the display modifier  624  which interchanges the symbols displayed at two or more different columns of display positions  740 . As discussed previously, in alternative embodiments, the display modifier  624  can be arranged to modify the displayed symbols only upon a modification condition being met (as determined by the modification condition determiner  626 ). In an embodiment, if the modification condition is not met, the game ends  760 . 
     As discussed previously, the modification of symbols can be displayed in many ways including as symbols shifting from one display position to another display position etc. 
     After the symbols of selected display positions are modified, the award determiner  628  determines whether to make an award based on the symbols displayed at the plurality of columns of display positions as modified  750 . 
     In an embodiment, the symbols displayed at the plurality of columns of display positions as modified may be modified again (that is, by again interchanging the symbols displayed at two or more different columns of display positions). This modification of symbols and determination of whether to make an award based on the modified symbols can be repeated any number of times. The number of times the process of modifying symbols and determining whether to make an award can be defined, random, or based on a particular criteria being satisfied (for example, until an award is made or all combinations are exhausted, until no award is made etc.). At step  760 , the game ends. In embodiments where the award determiner  628  has determined that multiple awards are to be made, an option may be displayed on a display to allow the player to select which one of the awards he or she wishes to take. 
     Further aspects of the method will be apparent from the above description of the system. It will be appreciated that at least part of the method will be implemented electronically, for example digitally by a processor. Persons skilled in the art will also appreciate that the method could be embodied in program code. The program code could be supplied in a number of ways, for example on a tangible computer readable storage medium, such as a disc or a memory (for example, that could replace part of memory  103 ) or as a data signal (for example, by transmitting it from a server). Persons skilled in the art, will appreciate that program code provides a series of instructions executable by the processor. 
     Example 
       FIGS. 8A and 8B  illustrate an example of how symbols displayed at two different columns or reels of display positions on the display  54  may be modified and displayed on display  54 . As shown in these figures, the game is a 5×3 spinning-reel type game having 5 reels of display positions (referred to as “Reel  1 ”, “Reel  2 ”, “Reel  3 ”, “Reel  4 ”, and “Reel  5 ” in  FIG. 8A ), each reel comprising 3 display positions arranged in a column. In this spinning-reel type game, there are 6 possible symbols that can be displayed at each display position. 
       FIG. 8A  illustrates a display of symbols initially selected by the symbols selector  623 . As illustrated, there are 3 triangle symbols displayed horizontally adjacent each other at the bottom-most row (sometimes referred to as “line  3 ”) of the display. Based on the displayed symbols, the award determiner  628  determines that a pay is to be credited to the player. In this example, the modification condition for modifying the displayed symbols is whether a pay is to be credited to a player prior to modifying the symbols. Thus, the modification condition determiner  626  determines that the modification condition for modifying the displayed symbols in this game is met. 
     Accordingly, the displayed symbols are then modified by the display modifier  624  by rearranging or interchanging the order of the reels. In this example, the display position selector  625  determines the new order of the reels based on predetermined rules for swapping reels stored in display data  644 . 
     After the new order of reels has been determined, the display controller  629  controls the display  54  to display the new order of reels. The new display of symbols is illustrated in  FIG. 8B . As shown, Reel  5  has been interchanged with Reel  2 , and Reel  4  has been interchanged with Reel  3 . 
     The award determiner  628  then determines whether an award should be made based on the symbols displayed at the 5 reels of display positions as modified. In this example, the award determiner  628  determines that two new pays may be credited to the player; one for the 4 star symbols stretching from Reel  1  to new Reel  4  or previous Reel  3  (sometimes referred to as “line  4 ”), and another for the 3 circle symbols in Reel  1 , new Reel  2  or previous Reel  5 , and new Reel  3  or previous Reel  4  (sometimes referred to as “line  18 ”). 
     It will be understood to persons skilled in the art of the invention that many modifications may be made without departing from the spirit and scope of the invention, in particular it will be apparent that certain features of embodiments of the invention can be employed to form further embodiments. 
     It is to be understood that, if any prior art is referred to herein, such reference does not constitute an admission that the prior art forms a part of the common general knowledge in the art in any country. 
     In the claims which follow and in the preceding description of the invention, except where the context requires otherwise due to express language or necessary implication, the word “comprise” or variations such as “comprises” or “comprising” is used in an inclusive sense, i.e. to specify the presence of the stated features but not to preclude the presence or addition of further features in various embodiments of the invention.