File: src/zerk/class/game/engine/entity.js
/**
* Entity
*
* All entities should inherit from here.
*
* @class zerk.game.engine.entity
* @extends zerk.observable
* @module zerk
*/
zerk.define({
name: 'zerk.game.engine.entity',
extend: 'zerk.observable'
},{
/**
* Fires when the entity gets spawned
*
* @event spawn
* @return {Boolean} Return false to Cancel bubble
*/
/**
* Fires every world simulation tick
*
* @event tick
* @return {Boolean} Return false to Cancel bubble
*/
/**
* Fires when two fixtures start colliding
*
* @event contactbegin
* @param {zerk.game.engine.physics.fixture} sourceFixture Source fixture
* @param {zerk.game.engine.physics.fixture} targetFixture Target fixture
* @return {Boolean} Return false to Cancel bubble
*/
/**
* Fires when two fixtures stop colliding
*
* @event contactend
* @param {zerk.game.engine.physics.fixture} sourceFixture Source fixture
* @param {zerk.game.engine.physics.fixture} targetFixture Target fixture
* @return {Boolean} Return false to Cancel bubble
*/
/**
* Fires before two fixtures start colliding
*
* @event contactpostsolve
* @param {zerk.game.engine.physics.fixture} sourceFixture Source fixture
* @param {zerk.game.engine.physics.fixture} targetFixture Target fixture
* @param {Object} impulse
* @return {Boolean} Return false to Cancel bubble
*/
/**
* Name of the entity
*
* @property name
* @type String
*/
name: '',
/**
* Width of the entity
*
* @property width
* @type Integer
*/
width: 0,
/**
* Height of the entity
*
* @property height
* @type Integer
*/
height: 0,
/**
* Class constructor
*
* @method init
* @param {zerk.game.engine} engine Game engine
* @param {Object} config Entity configuration
*/
init: function(engine) {
zerk.parent('zerk.game.engine.entity').init.apply(
this,
arguments
);
this._engine=engine;
this.joints=[];
this.sprites={};
// Extend default config with local config
this.config={
id: '',
x: 0,
y: 0,
bodies: [
]
};
},
/**
* Destroys this entity and removes it from the world
*
* @method destroy
*/
destroy: function() {
this._engine.world.destroy(this);
},
/**
* Entity setup method
*
* Entities should define their bodies and joints in this method
*
* @method setup
*/
setup: function() {
// Calculate initial positions relative to the origin body
var x=0.0;
var y=0.0;
var angle=0;
// Create positions for each body
if (this.config.bodies.length==0) {
for (var index in this.bodies) {
if (this.bodies[index].origin) {
x=this.config.x;
y=this.config.y;
if (this.config.angle) {
angle=this.config.angle;
} else {
angle=this.bodies[index].angle;
}
} else {
x=this.config.x+this.bodies[index].x;
y=this.config.y+this.bodies[index].y;
angle=this.bodies[index].angle;
}
this.config.bodies[this.bodies[index].key]={
x: x,
y: y,
angle: angle
};
}
}
for (var index in this.bodies) {
var extendedBody=zerk.create(
'zerk.game.engine.physics.body'
);
zerk.apply(extendedBody,this.bodies[index]);
extendedBody._entity=this;
this.bodies[index]=extendedBody;
var extendedFixture=null;
for (var indexTwo in this.bodies[index].fixtures) {
switch (this.bodies[index].fixtures[indexTwo].shape) {
case 'box':
extendedFixture=zerk.create(
'zerk.game.engine.physics.fixture.rectangle',
this.bodies[index]
);
break;
case 'circle':
extendedFixture=zerk.create(
'zerk.game.engine.physics.fixture.circle',
this.bodies[index]
);
break;
case 'polygon':
extendedFixture=zerk.create(
'zerk.game.engine.physics.fixture.polygon',
this.bodies[index]
);
break;
}
zerk.apply(
extendedFixture,
this.bodies[index].fixtures[indexTwo]
);
this.bodies[index].fixtures[indexTwo]=extendedFixture;
}
}
var extendedJoint=null;
for (var index in this.joints) {
switch (this.joints[index].type) {
case 'distance':
extendedJoint=zerk.create(
'zerk.game.engine.physics.joint.distance'
);
break;
case 'revolute':
extendedJoint=zerk.create(
'zerk.game.engine.physics.joint.revolute'
);
break;
}
zerk.apply(extendedJoint,this.joints[index]);
this.joints[index]=extendedJoint;
}
this._createMapBody();
},
/**
* Apply configuration object
*
* @method applyConfig
* @param {Object} config
*/
applyConfig: function(config) {
zerk.apply(
this.config,
config
);
},
/**
* Returns a body by key
*
* @method getBody
* @param {String} key Key of the body
* @return {zerk.game.engine.physics.body} Body instance
*/
getBody: function(key) {
return this._mapBody[key];
},
/**
* Create a map to the physics handles of all bodies by their keys
*
* @method _createMapBody
* @protected
*/
_createMapBody: function() {
this._mapBody={};
for (var index in this.bodies) {
this._mapBody[this.bodies[index].key]=this.bodies[index];
}
},
/**
* Applies an impulse to given body
*
* @method _bodyApplyImpulse
* @param {String} bodyKey
* @param {Integer} degrees
* @param {Integer} power
* @protected
*/
_bodyApplyImpulse: function(bodyKey,degrees,power) {
var physicsBody=this._mapBody[bodyKey].physicsHandle;
physicsBody.ApplyImpulse(
new this._engine.physics._b2Vec2(
Math.cos(degrees*(Math.PI/180))*power,
Math.sin(degrees*(Math.PI/180))*power
),
physicsBody.GetWorldCenter()
);
},
/**
* Sets the linear velocity of given body
*
* @method _setLinearVelocity
* @param {String} bodyKey
* @param {Integer} degrees
* @param {Integer} power
* @protected
*/
_setLinearVelocity: function(bodyKey,degrees,power) {
var physicsBody=this._mapBody[bodyKey].physicsHandle;
physicsBody.SetLinearVelocity(
new this._engine.physics._b2Vec2(
Math.cos(degrees*(Math.PI/180))*power,
Math.sin(degrees*(Math.PI/180))*power
)
);
},
/**
* Sets the position of given body
*
* @method _setBodyPosition
* @param {String} bodyKey
* @param {Object} position
* @protected
*/
_setBodyPosition: function(bodyKey,position) {
var physicsBody=this._mapBody[bodyKey].physicsHandle;
return physicsBody.SetPosition(position);
},
/**
* Sets whether given body is allowed to sleep
*
* @method _setBodySleepingAllowed
* @param {String} bodyKey
* @param {Boolean} allowed
* @protected
*/
_setBodySleepingAllowed: function(bodyKey,allowed) {
this.getBody(bodyKey).physicsHandle.SetSleepingAllowed(allowed);
},
/**
* Sets whether given body is moveable
*
* @method _setBodyMoveable
* @param {String} bodyKey
* @param {Boolean} moveable
* @protected
*/
_setBodyMoveable: function(bodyKey,moveable) {
var type=((moveable)
? this._engine.physics._b2Body.b2_dynamicBody
: this._engine.physics._b2Body.b2_staticBody);
this.getBody(bodyKey).physicsHandle.SetType(
type
);
},
/**
* Sets given body to be kinematic
*
* @method _setBodyKinematic
* @param {String} bodyKey
* @protected
*/
_setBodyKinematic: function(bodyKey) {
this.getBody(bodyKey).physicsHandle.SetType(
this._engine.physics._b2Body.b2_kinematicBody
);
},
/**
* Returns position of given body
*
* @method _getBodyPosition
* @param {String} bodyKey
* @return {Object} Position
* @protected
*/
_getBodyPosition: function(bodyKey) {
return this.getBody(bodyKey).physicsHandle.GetPosition();
},
/**
* Returns the linear velocity of given body
*
* @method _getBodyLinearVelocity
* @param {String} bodyKey
* @return {Object}
* @protected
*/
_getBodyLinearVelocity: function(bodyKey) {
return this.getBody(bodyKey).physicsHandle.GetLinearVelocity();
},
/**
* Destroys given body
*
* @method _destroyBody
* @param {String} bodyKey
* @protected
*/
_destroyBody: function(bodyKey) {
var found=false;
for (var i=0;i<this.bodies.length;i++) {
if (this.bodies[i].key==bodyKey) {
found=true;
break;
}
}
if (!found) return;
this._engine.physics.scheduleDestroyBody(
this,
this.getBody(bodyKey)
);
this.bodies.splice(i,1);
return true;
}
});
