Frees the resources allocated by graphene_quad_alloc()
Initializes a #graphene_quad_t with the given points.
the first point of the quadrilateral
the second point of the quadrilateral
the third point of the quadrilateral
the fourth point of the quadrilateral
Allocates a new #graphene_quad_t instance.
The contents of the returned instance are undefined.
A 4 vertex quadrilateral, as represented by four #graphene_point_t.
The contents of a #graphene_quad_t are private and should never be accessed directly.