for (Fixture fixture = body.getFixtureList(); fixture != null; fixture = fixture.getNext()) {
Shape shape = fixture.getShape();
if (shape.getType() == ShapeType.CIRCLE) {
CircleShape circle = (CircleShape)shape;
context.beginPath();
context.arc(circle.m_p.x, circle.m_p.y, circle.getRadius(), 0, Math.PI * 2, true);
context.closePath();
context.stroke();
} else if (shape.getType() == ShapeType.POLYGON) {
PolygonShape poly = (PolygonShape)shape;
Vec2[] vertices = poly.getVertices();