Box2d dynamic body stuck to static

Sometimes, when dynamic body moving and collide static body, dynamic stuck, and stopping.

http://imageshack.us/photo/my-images/14/screenfgz.png/ (top and bottom lines are sensors, center shape is body)

For moving used mouseJoint->SetTarget(pos);

Settings: World

b2Vec2 gravity = b2Vec2(0.f, 0.f);
bool doSleep = true;
world = new b2World(gravity, doSleep);
world->SetContinuousPhysics(false); // when using true, dynamic tunneling through other bodies

Dynamic body

...
density = 1.f;
friction = 0.f;
restitution = 0.f;
...
body->SetBullet(true);
body->SetFixedRotation(true);

MouseJoint

  b2Vec2 locationWorld = b2Vec2(pos.x/PTM_RATIO,pos.y/PTM_RATIO);
    b2MouseJointDef md;                
    md.bodyA = groundBody;
    md.bodyB = body;
    md.target = body->GetPosition();
    md.collideConnected = true;
    md.maxForce = 1000 * body->GetMass();
    md.dampingRatio = 0.1f;
    md.frequencyHz = 2.f;
    mouseJoint = (b2MouseJoin开发者_JAVA百科t *)world->CreateJoint(&md);

Dynamic and static bodies are rectangles. Rotation = 0.

How remove stucking?

If you are seeing the dynamic box getting caught on the tiles in the static body as it seems from the screenshot, this is a known issue in Box2D at the moment. You could improve it by using one large polygon for the static body, or a loop shape, or simply bevel the corners of the dynamic body so they are not perfectly square.

Solution: use edges for create fixture (at dynamic and static bodies)

shape.SetAsEdge(b2Vec2(x,y),b2Vec2(x2,y2));
bodyWall->CreateFixture(&shapeDef);

instead

shape.SetAsBox(width,height, b2Vec2(x,y),angle);