Digicards: An app for all card games

Erik Nord

www.eriknord.no

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Background and aim

Sometimes people want to play cards, but do not have a deck of cards at hand, or they sit too far apart to play with real cards. By representing cards and game structures on cell phones and connecting players via the internet, one may fill both gaps. Apps for this purpose exist for a number of card games, for instance for bridge.

Below I describe a planned app with two major advantages compared to existing ones.

Firstly, it will allow users to play any card game without the app having any knowledge of game rules. The approach thus provides universal applicability without burdening developers with an immense task of game specific programming.

Secondly, it will in any card game enable tournaments of the kind practised in the game of bridge, in which the element of ‘luck with one’s cards’ is eliminated such that results are determined by skill only.

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1 Exploiting the common core of card games

All card games consist in moving cards between different locations. Possible locations include the hands of the players (all card games), personal table space for each player for laying down cards face up or face down at the initial deal or during the game (as in rummy), places on the table with stacks for drawing and discarding (as in rummy), a place for laying down cards next to each other for all players’ use (as in casino), and a place for players to lay down a card when contributing to a trick (as in bridge).

The physical essence of card games is visualized in the figure below. It pertains to a game with six players. With fewer players, one or more hands may be omitted and more space becomes available for the remaining ones (see below).

S4	H4									Explanation of symbols: H: Cards on hand. T: Cards on personal table space. P: Card laid down in trick. D1: Stack from which cards are drawn. D2: Place for discarding. C: Common ground for cards placed next to each other, where all players can operate. F1-F4: Buttons for functions like ‘Store trick’, ‘Collect cards’, ‘Turn completed’etc. S: Places for registering score.
	P4	T4							S5
H3									H5
	P3							P5
	T3					T5
S3
		D1		C
		D2
		F1	F2	F3			F4		S6
H2	T2				T6				H6
	P2							P6
		T1
S2								P1
	H1								S1

Using this model as a starting point, an app may be developed in which players first state how many they are and decide which card game they wish to play. If the game is known to the app (the most common ones will be included from the start), it selects the relevant card locations for that game and deals the appropriate number of cards to each relevant location. For a game new to the app, players state its name, its relevant locations and the number of cards to be dealt to each of these. The information will be included in the app’s database to allow direct access by game name later.

The layout of the table (the figure above) will change in accordance with the chosen number of players and the chose game. In most cases the change will be to something clearly simpler. Here is an example, applying to four players in the game of rummy:

S3	H3
		T3
					S4
H2					H4
	T2			T4
			Draw
			Discard
S2		T1
	H1				S1

Areas are rotated across participating cell phones so that each player has his or her own area in the lower end of the display (as H1 etc above). Each player sees the cards on his or her own hand, all cards on the table (lying with or without face up), and cards with face down on the other players’ hands.

Participants play by touching cards and the location to which they wish to move each card, and use function buttons (F1-F4, see examples above) when necessary. The latest move made is marked for the next player by blinking or the like.

Since the app has no knowledge of rules it does not reject any move. The players are themselves in charge and adhere to the rules of the game as they know them. It is up to fellow players to protest if a rule is violated, in which case an ‘undo button’ is pressed and the player in question plays again. This is as with real cards.

The basic version of the app has no knowledge of scoring. Players calculate and register scores themselves. Over time a more advanced version may be developed in which scoring for the most common games is included.

2 Enabling tournaments with equal luck with the cards

In all card games, there is an element of luck in terms of the goodness of the cards one happens to receive. In the game of bridge, there are tournaments in which the luck element is reduced by making comparisons across tables between players that hold the same cards and face the same opposition. The comparisons are possible because in bridge, each player’s cards in a given game are taken from a pocket in a folder, laid down in a row before the player as the game proceeds - without being mixed with other cards, and returned to the same pocket when the game is over. The initial distribution of cards on the four players is thus ‘reconstructed’. The folder travels from table to table. The same game is thus played by different players.

In other card games, cards are inevitably mixed during the game, such that reconstruction of initial distributions, as well as possible additional dealings throughout the game, is difficult, if not completely unfeasible. A digital solution handles this easily. The app described here will register each deal and be able to repeat it for any number of other players. It will thus allow tournaments based on the principle of equal luck with the cards – as practised in bridge - to be introduced in all other card games.

Here is a simple demonstration of how different card games may be chosen and laid out