memcpy-fastest.lisp

(defun cocoa-build-sprite (sprite image mask size)
  (declare #.*optimize*
           (type fixnum size))
  (loop for i fixnum from 0 below size
     for ii fixnum from 0 by 3
     for si fixnum from 0 by 4
     for alpha fixnum = ii
     for sr fixnum = si
     for sg fixnum = (1+ sr)
     for sb fixnum = (1+ sg)
     for sa fixnum = (1+ sb)
     for ir fixnum = ii
     for ig fixnum = (1+ ir)
     for ib fixnum = (1+ ig) do
     ;; copy color channels
     (setf (opengl:gl-vector-aref sprite sr)
           (the fixnum (opengl:gl-vector-aref image ir)))
     (setf (opengl:gl-vector-aref sprite sg)
           (the fixnum (opengl:gl-vector-aref image ig)))
     (setf (opengl:gl-vector-aref sprite sb)
           (the fixnum (opengl:gl-vector-aref image ib)))
     ;; set alpha from mask
     (setf (opengl:gl-vector-aref sprite sa)
           (the fixnum (opengl:gl-vector-aref mask alpha)))
     ))