I realize this may be a case of "Doctor, it hurts when I do this..", but I'm hoping there is some medicine to be had.

I'm displaying images from my raytracer on a canvas as they are being rendered. I don't require per pixel updating -- any buffering scheme that updates the screen "every once in a while" is fine by me.

Below is what I have now, and it sucks royally: DRAW-PIXEL* calls take ~8 seconds on a 400*600 region, and everything else takes < 1 second... (on CLX backend.)

(defun render-scene (scene medium) (let* ((pixmap nil) (region (sheet-region medium)) (width (bounding-rectangle-width region)) (height (bounding-rectangle-height region)) (end (- width 1))) (unwind-protect (progn (setf pixmap (allocate-pixmap medium width height)) (raylisp::render scene (raylisp::scene-default-camera scene) width height (lambda (color x y) (declare (type (simple-array single-float (3)) color) (type fixnum x y)) (progn (draw-point* pixmap x y :ink (make-rgb-color (aref color 0) (aref color 1) (aref color 2))) (when (= x end) (copy-from-pixmap pixmap 0 y width 1 medium 0 y)))) :normalize-camera t)) (when pixmap (deallocate-pixmap pixmap)))))

What I would like (and what the above tries to do, but fails) is to get hold of a some sort of object onto which I can efficiently blast colors pixel by pixel, and then update the screen using a convenient-for-me interval.

Cheers,

-- Nikodemus