var Fighter = cc.PhysicsSprite.extend({

         hitPoints: true,        //当前的生命值

         space: null,            //所在物理空间

         ctor: function (spriteFrameName, space) {

             this._super(spriteFrameName);

             this.space = space;

             var verts = [

                 -94, 31.5,

                 -52, 64.5,

                 57, 66.5,

                 96, 33.5,

                 0, -80.5];

             this.body = new cp.Body(1, cp.momentForPoly(1, verts, cp.vzero));

             this.body.data = this;

             this.space.addBody(this.body);

             var shape = new cp.PolyShape(this.body, verts, cp.vzero);

             shape.setElasticity(0.5);

             shape.setFriction(0.5);

             shape.setCollisionType(Collision_Type.Fighter);

             this.space.addShape(shape);

             this.hitPoints = Fighter_hitPoints;

             var ps = new cc.ParticleSystem(res.fire_plist);

             //在飞机下面.

             ps.x = this.getContentSize().width / 2;

             ps.y = 0;

             //ps.setRotation(180.0);

             ps.setScale(0.5);

             this.addChild(ps);

         },

         //重写setPosition

         setPosition: function (newPosition) {

             var halfWidth = this.getContentSize().width / 2;

             var halfHeight = this.getContentSize().height / 2;

             var pos_x = newPosition.x;

             var pos_y = newPosition.y;

             if (pos_x < halfWidth) {

                 pos_x = halfWidth;

             } else if (pos_x > (winSize.width - halfWidth)) {

                 pos_x = winSize.width - halfWidth;

             }

             if (pos_y < halfHeight) {

                 pos_y = halfHeight;

             } else if (pos_y > (winSize.height - halfHeight)) {

                 pos_y = winSize.height - halfHeight;

             }

             this.body.setPos(cc.p(pos_x, pos_y));

         }

     })  ;