// SetLayers sets layers bitmask of the shape. Shapes collide only if bitwise
// of their layers is non-zero.
func (s shapeBase) SetLayers(l Layers) {
C.cpShapeSetLayers(s.c(), l.c())
}
func (s *Shape) SetLayers(layer Layer) {
C.cpShapeSetLayers(s.shape, C.cpLayers(C.uint(layer)))
}