/* Note that the definition of this function is a bit odd because of the X coordinate space (y increasing downwards).  */
static int clockwise(const pixman_point_fixed_t *ref, const pixman_point_fixed_t *a, const pixman_point_fixed_t *b)
/* Note that the definition of this function is a bit odd because of the X coordinate space (y increasing downwards).  */
static int clockwise(const pixman_point_fixed_t *ref, const pixman_point_fixed_t *a, const pixman_point_fixed_t *b)
{
    pixman_point_fixed_t	ad, bd;
    ad.x = a->x - ref->x;
    ad.y = a->y - ref->y;
    bd.x = b->x - ref->x;
    bd.y = b->y - ref->y;
    return ((pixman_fixed_32_32_t) bd.y * ad.x -
	    (pixman_fixed_32_32_t) ad.y * bd.x) < 0;
}