Gaming system, gaming controller, and a prize triggering method

1. A triggering method for a win outcome for play of a game on a gaming device, the method comprising:

determining an amount of credit to wager on the game on commencement of game play on the gaming device, wherein the game comprises displaying a predefined plurality of symbols in respective initial display positions on a display of the gaming device, a winning outcome being defined by predetermined combinations of symbols displayed in the respective initial display positions; and

setting a plurality of additional display positions to be displayed in the game in addition to the initial display positions, such that the total number of display positions displayed is proportional to the amount of credit wagered on the game, wherein wagering additional credit on play of the game thereby affects the probability of a win outcome being generated as a result of an increased number of total display positions, wherein the plurality of additional display positions are randomly positioned adjacent to one of the plurality of initial display positions, and wherein respective additional display positions are only active if they are adjacent an active initial display position.

2. A method as claimed in claim 1 , further comprising satisfying a trigger condition when a specific symbol combination is displayed.

3. A method as claimed in claim 1 , wherein the number of symbols displayed is increased by a particular amount when the amount of credit bet exceeds or meets a specific value.

4. A method as claimed in claim 1 , wherein the game is a reel game and the number of symbols displayed is dependent on an amount bet per payline selected in the reel game.

5. A method as claimed in claim 2 , comprising causing a feature game to commence, a prize to be awarded, or multiplying a prize for a winning outcome when the trigger condition is satisfied.

6. A method as claimed in claim 3 , wherein the particular amount corresponds to the amount bet.

7. A jackpot triggering method for symbol jackpots, the method comprising:

determining an amount of credit to wager on the game on commencement of game play on the gaming device, wherein the game comprises displaying a predefined plurality of symbols in respective initial display positions on a display of the gaming device, a winning outcome being defined by predetermined combinations of symbols displayed in the respective initial display positions; and

setting a plurality of additional display positions to be displayed in the game in addition to the initial display positions, such that the total number of display positions displayed is proportional to the amount of credit wagered on the game, wherein wagering additional credit on play of the game thereby affects the probability of a win outcome being generated as a result of an increased number of total display positions, wherein the plurality of additional display positions are randomly positioned adjacent to one of the plurality of initial display positions, and wherein respective additional display positions are only active if they are adjacent an active initial display position.

8. A method as claimed in claim 7 , wherein a correct symbol combination causes the jackpot to be awarded to the player.

9. A method as claimed in claim 7 , wherein a correct symbol combination invokes an additional game that provides the player with an opportunity to win the jackpot.

10. A method as claimed in claim 7 , wherein a plurality of jackpots are available, each jackpot requiring a different symbol combination.

11. A controller arranged to control play of a game on a gaming device, the controller comprising:

a betting module operable to determine an amount of credit to wager on the game on commencement of game play on the gaming device, wherein the game comprises displaying a predefined plurality of symbols in respective initial display positions on a display of the gaming device, a winning outcome being defined by predetermined combinations of symbols displayed in the respective initial display positions; and

a display module operable to set a plurality of additional display positions to be displayed in the game in addition to the initial display positions, such that the total number of display positions displayed is proportional to the amount of credit wagered on the game, wherein wagering additional credit on play of the game thereby affects the probability of a win outcome being generated as a result of an increased number of total display positions, wherein the plurality of additional display positions are randomly positioned adjacent to one of the plurality of initial display positions, and wherein respective additional display positions are only active if they are adjacent an active initial display position.

12. A controller as claimed in claim 11 , further comprising a trigger module arranged to invoke a trigger condition upon determining that a specific symbol combination is displayed on the gaming device.

13. A controller as claimed in claim 11 , wherein the number of symbols displayed is increased by a particular value when the amount of credit bet exceeds or meets a specific value.

14. A controller as claimed in claim 11 , wherein the game is a reel game and the number of symbols displayed is dependent on an amount bet per payline selected in the reel game.

15. A controller as claimed in claim 12 , comprising causing a feature game to commence, a prize to be awarded, or multiplying a prize for a winning outcome when the trigger condition is invoked.

16. A controller as claimed in claim 13 , wherein the particular value corresponds to the amount bet.

17. A gaming system comprising:

a plurality of gaming devices which may participate in a jackpot by making jackpot contributions; and

a jackpot controller arranged to:

for each of the plurality of gaming devices, determine an amount of credit to wager on the game on commencement of game play on the gaming device, wherein the game comprises displaying a predefined plurality of symbols in respective initial display positions on a display of the gaming device, a winning outcome being defined by predetermined combinations of symbols displayed in the respective initial display positions; and set a plurality of additional display positions to be displayed in the game in addition to the initial display positions, such that the total number of display positions displayed is proportional to the amount of credit wagered on the game, wherein wagering additional credit on play of the game thereby affects the probability of a win outcome being generated as a result of an increased number of total display positions, wherein the plurality of additional display positions are randomly positioned adjacent to one of the plurality of initial display positions, and wherein respective additional display positions are only active if they are adjacent an active initial display position.

18. A gaming system comprising:

a display operable to display a predefined plurality of initial symbol positions and optionally one or more additional symbol positions;

a betting module arranged to determine an amount wagered on a game on commencement of the game;

a symbol selector arranged to select symbols for display in the plurality of initial symbol positions, a winning outcome being defined by predetermined combinations of symbols displayed in the respective initial display positions, and, dependent on the amount wagered, further arranged to select and display symbols in the additional symbol position(s); and

an outcome determiner arranged to determine an outcome of the game based on the displayed symbols,

wherein the plurality of additional display positions displayed in the game in addition to the initial display positions is set such that the total number of display positions is proportional to the amount of credit wagered on the game, wherein wagering additional credit on play of the game thereby affects the probability of a win outcome being generated as a result of an increased number of total display positions, wherein the plurality of additional display positions are randomly positioned adjacent to one of the plurality of initial display positions, and wherein respective additional display positions are only active if they are adjacent an active initial display position.

19. A gaming system as claimed in claim 18 , wherein the symbol selector displays a symbol in the additional symbol position(s) when the amount bet meets or exceeds a designated threshold.

20. A gaming system as claimed in claim 18 , wherein the system is arranged such that when a particular number or combination of symbols are displayed in the standard and/or additional symbol positions, a trigger condition is satisfied.

21. A gaming system as claimed in claim 18 , wherein the plurality of standard symbols are displayed in a format having an array of rows and columns and whereby the or each additional symbol position is associated with one of the rows or columns.

22. A gaming system as claimed in claim 20 , wherein the trigger condition causes a feature game to commence, triggers a win outcome, or multiplies a prize awarded for a winning outcome.

23. A gaming system as claimed in claim 22 , wherein the win outcome is the awarding of a jackpot prize.

24. A gaming system as claimed in claim 21 , wherein the system is arranged such that standard symbol positions define at least one player selectable payline used to determine a game outcome, and such that symbols displayed in the additional symbol position(s) can also form part of a payline dependent on their location.

25. A gaming system as claimed in claim 24 , wherein the row or column with which the, or each, additional symbol position is associated is randomly determined.

26. A tangible computer readable storage medium comprising computer program code which when executed implements a triggering method for a win outcome on a gaming device, the method comprising:

determining an amount of credit to wager on the game on commencement of game play on the gaming device, wherein the game comprises displaying a predefined plurality of symbols in respective initial display positions on a display of the gaming device, a winning outcome being defined by predetermined combinations of symbols displayed in the respective initial display positions; and

setting a plurality of additional display positions to be displayed in the game in addition to the initial display positions, such that the total number of display positions displayed is proportional to the amount of credit wagered on the game, wherein wagering additional credit on play of the game thereby affects the probability of a win outcome being generated as a result of an increased number of total display positions, wherein the plurality of additional display positions are randomly positioned adjacent to one of the plurality of initial display positions, and wherein respective additional display positions are only active if they are adjacent an active initial display position.