static public void add_box(cpSpace space, int index, float size)
{
float mass = size * size / 100.0f;
cpBody body = space.AddBody(new cpBody(mass, cp.MomentForBox(mass, size, size)));
// cpBody body = cpSpaceAddBody(space, cpBodyInit(&bodies[i], mass, cpMomentForBox(mass, size, size)));
body.SetPosition(cpVect.cpvmult(cp.frand_unit_circle(), 180.0f));
cpPolyShape shape = space.AddShape(cpPolyShape.BoxShape(body, size - bevel * 2f, size - bevel * 2f, 0f)) as cpPolyShape;
shape.SetRadius(bevel);
shape.SetElasticity(0.0f);
shape.SetFriction(0.9f);
}
