File: src/shapes/Shape.js
module.exports = Shape;
/**
* Base class for shapes.
* @class Shape
* @constructor
* @param {Number} type
*/
function Shape(type){
/**
* The type of the shape. One of:
*
* * {{#crossLink "Shape/CIRCLE:property"}}Shape.CIRCLE{{/crossLink}}
* * {{#crossLink "Shape/PARTICLE:property"}}Shape.PARTICLE{{/crossLink}}
* * {{#crossLink "Shape/PLANE:property"}}Shape.PLANE{{/crossLink}}
* * {{#crossLink "Shape/CONVEX:property"}}Shape.CONVEX{{/crossLink}}
* * {{#crossLink "Shape/LINE:property"}}Shape.LINE{{/crossLink}}
* * {{#crossLink "Shape/RECTANGLE:property"}}Shape.RECTANGLE{{/crossLink}}
* * {{#crossLink "Shape/CAPSULE:property"}}Shape.CAPSULE{{/crossLink}}
* * {{#crossLink "Shape/HEIGHTFIELD:property"}}Shape.HEIGHTFIELD{{/crossLink}}
*
* @property {number} type
*/
this.type = type;
/**
* Shape object identifier.
* @type {Number}
* @property id
*/
this.id = Shape.idCounter++;
/**
* Bounding circle radius of this shape
* @property boundingRadius
* @type {Number}
*/
this.boundingRadius = 0;
/**
* Collision group that this shape belongs to (bit mask). See <a href="http://www.aurelienribon.com/blog/2011/07/box2d-tutorial-collision-filtering/">this tutorial</a>.
* @property collisionGroup
* @type {Number}
* @example
* // Setup bits for each available group
* var PLAYER = Math.pow(2,0),
* ENEMY = Math.pow(2,1),
* GROUND = Math.pow(2,2)
*
* // Put shapes into their groups
* player1Shape.collisionGroup = PLAYER;
* player2Shape.collisionGroup = PLAYER;
* enemyShape .collisionGroup = ENEMY;
* groundShape .collisionGroup = GROUND;
*
* // Assign groups that each shape collide with.
* // Note that the players can collide with ground and enemies, but not with other players.
* player1Shape.collisionMask = ENEMY | GROUND;
* player2Shape.collisionMask = ENEMY | GROUND;
* enemyShape .collisionMask = PLAYER | GROUND;
* groundShape .collisionMask = PLAYER | ENEMY;
*
* @example
* // How collision check is done
* if(shapeA.collisionGroup & shapeB.collisionMask)!=0 && (shapeB.collisionGroup & shapeA.collisionMask)!=0){
* // The shapes will collide
* }
*/
this.collisionGroup = 1;
/**
* Whether to produce contact forces when in contact with other bodies. Note that contacts will be generated, but they will be disabled. That means that this shape will move through other body shapes, but it will still trigger contact events, etc.
* @property {Boolean} collisionResponse
*/
this.collisionResponse = true;
/**
* Collision mask of this shape. See .collisionGroup.
* @property collisionMask
* @type {Number}
*/
this.collisionMask = 1;
if(type){
this.updateBoundingRadius();
}
/**
* Material to use in collisions for this Shape. If this is set to null, the world will use default material properties instead.
* @property material
* @type {Material}
*/
this.material = null;
/**
* Area of this shape.
* @property area
* @type {Number}
*/
this.area = 0;
/**
* Set to true if you want this shape to be a sensor. A sensor does not generate contacts, but it still reports contact events. This is good if you want to know if a shape is overlapping another shape, without them generating contacts.
* @property {Boolean} sensor
*/
this.sensor = false;
this.updateArea();
}
Shape.idCounter = 0;
/**
* @static
* @property {Number} CIRCLE
*/
Shape.CIRCLE = 1;
/**
* @static
* @property {Number} PARTICLE
*/
Shape.PARTICLE = 2;
/**
* @static
* @property {Number} PLANE
*/
Shape.PLANE = 4;
/**
* @static
* @property {Number} CONVEX
*/
Shape.CONVEX = 8;
/**
* @static
* @property {Number} LINE
*/
Shape.LINE = 16;
/**
* @static
* @property {Number} RECTANGLE
*/
Shape.RECTANGLE = 32;
/**
* @static
* @property {Number} CAPSULE
*/
Shape.CAPSULE = 64;
/**
* @static
* @property {Number} HEIGHTFIELD
*/
Shape.HEIGHTFIELD = 128;
/**
* Should return the moment of inertia around the Z axis of the body given the total mass. See <a href="http://en.wikipedia.org/wiki/List_of_moments_of_inertia">Wikipedia's list of moments of inertia</a>.
* @method computeMomentOfInertia
* @param {Number} mass
* @return {Number} If the inertia is infinity or if the object simply isn't possible to rotate, return 0.
*/
Shape.prototype.computeMomentOfInertia = function(mass){
throw new Error("Shape.computeMomentOfInertia is not implemented in this Shape...");
};
/**
* Returns the bounding circle radius of this shape.
* @method updateBoundingRadius
* @return {Number}
*/
Shape.prototype.updateBoundingRadius = function(){
throw new Error("Shape.updateBoundingRadius is not implemented in this Shape...");
};
/**
* Update the .area property of the shape.
* @method updateArea
*/
Shape.prototype.updateArea = function(){
// To be implemented in all subclasses
};
/**
* Compute the world axis-aligned bounding box (AABB) of this shape.
* @method computeAABB
* @param {AABB} out The resulting AABB.
* @param {Array} position
* @param {Number} angle
*/
Shape.prototype.computeAABB = function(out, position, angle){
// To be implemented in each subclass
};