phaser/Phaser/physics/aabb/ProjAABBConvex.ts

/// <reference path="../../_definitions.ts" />

/**
* Phaser - Physics - Projection
*/

module Phaser.Physics.Projection {

    export class AABBConvex {

        public static Collide(x: number, y: number, obj: Phaser.Physics.AABB, t: Phaser.Physics.TileMapCell) {

            //if distance from "innermost" corner of AABB is less than than tile radius,
            //collision is occuring and we need to project

            var signx = t.signx;
            var signy = t.signy;

            var ox = (obj.pos.x - (signx * obj.width)) - (t.pos.x - (signx * t.xw));//(ox,oy) is the vector from the circle center to
            var oy = (obj.pos.y - (signy * obj.height)) - (t.pos.y - (signy * t.yw));//the AABB
            var len = Math.sqrt(ox * ox + oy * oy);

            var twid = t.xw * 2;
            var rad = Math.sqrt(twid * twid + 0);//this gives us the radius of a circle centered on the tile's corner and extending to the opposite edge of the tile;
            //note that this should be precomputed at compile-time since it's constant

            var pen = rad - len;
            if (((signx * ox) < 0) || ((signy * oy) < 0))
            {
                //the test corner is "outside" the 1/4 of the circle we're interested in
                var lenP = Math.sqrt(x * x + y * y);
                obj.reportCollisionVsWorld(x, y, x / lenP, y / lenP, t);

                return Phaser.Physics.AABB.COL_AXIS;//we need to report 		
            }
            else if (0 < pen)
            {
                //project along corner->circle vector
                ox /= len;
                oy /= len;
                obj.reportCollisionVsWorld(ox * pen, oy * pen, ox, oy, t);

                return Phaser.Physics.AABB.COL_OTHER;
            }

            return Phaser.Physics.AABB.COL_NONE;
        }

    }
}