线关节(Line Joint)

 1 package{
 2     import Box2D.Common.Math.b2Vec2;
 3     import Box2D.Dynamics.b2Body;
 4     import Box2D.Dynamics.Joints.b2LineJointDef;
 5     import Box2D.Dynamics.Joints.b2PrismaticJointDef;
 6 
 7     /**
 8     * 线关节，限制一个刚体只能在一个轴向上移动
 9     */
10     public class Main extends BaseMain{
11         
12         
13         public function Main(){
14             super(new b2Vec2(0,10));
15         }
16         
17         override protected function init():void{
18             var bodyA:b2Body=this.createBox(50,50,400,300);
19             var bodyB:b2Body=this.createCircle(25,400,300);
20             bodyA.SetType(b2Body.b2_staticBody);
21             
22             var jointDef:b2LineJointDef=new b2LineJointDef();
23             var anchor:b2Vec2=bodyA.GetWorldCenter();
24             var axis:b2Vec2=new b2Vec2(1,0);
25             jointDef.Initialize(bodyA,bodyB,anchor,axis);
26             _world.CreateJoint(jointDef);
27             
28         }
29         
30         
31     };
32 }