API.md

Rx Training Games provides a basic API for building games.

Squares of different colors are switched on and off in a graphical square grid :

The grid is first instantiated with the size of the activable squares : api.initGrid({squareSize: 15});

Layers

Multiple layers with different colors can be added with var layer = api.addLayer({color: '#337ab7'});

A layer exposes the following methods :

• layer.fill({x: 42, y: 42}); : activate a square
• layer.clear({x: 42, y: 42}); : clear a square
• layer.getActiveSquares(); : retrieve a list of active squares

The layer is also implemented as an Observable Collection and provides two Observables :

// square activations
layer.activations.subscribe(coord =>
    console.log(coord.x + ',' + coord.y + ' has been activated')
);

// square removals
layer.removals.subscribe(coord =>
    console.log(coord.x + ',' + coord.y + ' has been cleared')
);

Keyboard events

Keyboard events are accessible using an Observable :

// keyboard events
api.keyboard.subscribe(keyCode =>
    console.log(keyCode)
);

Directions

Most games have the concept of directions : Left, Up, Right and Down.

The API exposes these directions as well as convenient methods in api.directions object.

Both key codes and human readable names are available console.log(_.keys(api.directions)) :

["37", "38", "39", "40", "Left", "Up", "Right", "Down"]

These keys can be used to

Filter keyboard events :

var directionKeys = api.keyboard.filter(keyCode =>
    keyCode in api.directions
);

Update coordinates :

// using key identifier
var newCoord = api.directions.Up({x: 42, y: 42});

// using key code
var newCoord = api.directions['38']({x: 42, y: 42});

Miscellaneous methods

• api.gameSize() : return the number of rows/columns
• api.setText({text: 'Score : 42'}) : display text in the grid
• api.randomSquare() : generate random valid xy coordinates ({x: ?, y: ?})
• api.randomCoord() : generate a random valid coordinate ({x: api.randomCoord(), y: 42})
• api.isOffLimits({x: 42, y: 42}) : return true if xy coordinates fall outside the grid
• api.isWithinLimits({x: 42, y: 42}) : return true xy coordinates fall inside the grid
• api.gameOver() : end the game

Contributing code samples

Do you think you can invent games with these simple elements? See how to contribute.