/* multiply 8-bit fixpoint (0..1) so that 0*0==0 and 255*255==255 */#define fz_mul255(a,b) (((a) * ((b) + 1)) >> 8)#define fz_floor(x) floor(x)#define fz_ceil(x) ceil(x)/* divide and floor towards -inf */static inline int fz_idiv(int a, int b){	return a < 0 ? (a - b + 1) / b : a / b;}/* from python */static inline void fz_idivmod(int x, int y, int *d, int *m){	int xdivy = x / y;	int xmody = x - xdivy * y;	/* If the signs of x and y differ, and the remainder is non-0,	 * C89 doesn't define whether xdivy is now the floor or the	 * ceiling of the infinitely precise quotient.  We want the floor,	 * and we have it iff the remainder's sign matches y's.	 */	if (xmody && ((y ^ xmody) < 0)) {		xmody += y;		xdivy --;	}	*d = xdivy;	*m = xmody;}