Platform

A platform is a entity in the game which the character stands on, runs on, and jumps to and from.

A gma.platform is defined by it’s dimensions (height, width, depth) and position (x, y). As with all rectangles, this can be specified in many different ways. For example:

// 3 ways to specify the same platform.
gma.platform({depth:20, left:10, width:20, bottom:10, height:5});
gma.platform({depth:20, left:10, right:30, bottom:10, top:15});
gma.platform({depth:20, x:20,    width:20, y:12.5,    height:5});

A non-solid platform

Platforms can also be defined as solid or not via it’s gma.platform.solid property. If this is set to false, then nothing can collide with the platform,i.e. entities will go through it.

var cloud = gma.platform({
    x:0, y:0, width:1, height:1, depth: 20
    solid: false
});

A deadly platform

Platforms support the deathtouch tag. A platform with deathtouch will “kill” any gma.character that hits it. This tag is already specified when you create a platform using gma.deathPlatform.

var lava = gma.deathPlatform({
    x:10, y:-1, width:10, height:1, depth: 20
});

// Is equivalent to:
var lava = gma.platform({
    x:10, y:-1, width:10, height:1, depth: 20
    tags : ["deathtouch"]
});

Adding platforms to your game

To add platforms to your game, they must be added to a level specification, which is stored on the manager and loaded. The example platforms above could be added to a level like this:

var aLevel = {
    types : {
        lava: ['deathplatform', {}]
    },
    entities : [
        // Normal Platform. Note the default entity type is platform
        {left:10, bottom:10, width:20, height:5, depth:20},

        // Non-solid platform
        {solid:false, x:0, y:0,  width:1, height:1, depth: 20},

        // Death Platform
        {type:"lava", x:0, y:-1, width:10, height:1, depth:20}
    ]
};

// Then add level to manager
manager.storeLevels(aLevel);

See Adding Entities and Types (in the levels topic) for an explanation of how the above code works. (Particularly, to explain why we don’t need to explicitly use gma.deathPlatform and gma.platform.)