- (or (consp rule)
- (error "Invalid composition rule: %S" rule))
- (let ((gref (car rule))
- (nref (cdr rule)))
- (or (integerp gref)
- (setq gref (cdr (assq gref reference-point-alist))))
- (or (integerp nref)
- (setq nref (cdr (assq nref reference-point-alist))))
- (or (and (>= gref 0) (< gref 12) (>= nref 0) (< nref 12))
- (error "Invalid composition rule: %S" rule))
- (+ (* gref 12) nref))))
+ (if (consp rule)
+ (let ((gref (car rule))
+ (nref (cdr rule))
+ xoff yoff)
+ (if (consp nref) ; (GREF NREF XOFF YOFF)
+ (progn
+ (setq xoff (nth 1 nref)
+ yoff (nth 2 nref)
+ nref (car nref))
+ (or (and (>= xoff -100) (<= xoff 100)
+ (>= yoff -100) (<= yoff 100))
+ (error "Invalid compostion rule: %s" rule))
+ (setq xoff (+ xoff 128) yoff (+ yoff 128)))
+ ;; (GREF . NREF)
+ (setq xoff 0 yoff 0))
+ (or (integerp gref)
+ (setq gref (cdr (assq gref reference-point-alist))))
+ (or (integerp nref)
+ (setq nref (cdr (assq nref reference-point-alist))))
+ (or (and (>= gref 0) (< gref 12) (>= nref 0) (< nref 12))
+ (error "Invalid composition rule: %S" rule))
+ (logior (lsh xoff 16) (lsh yoff 8) (+ (* gref 12) nref)))
+ (error "Invalid composition rule: %S" rule))))