RosettaCodeData/Task/Image-noise/Common-Lisp/image-noise.lisp
2015-02-20 00:35:01 -05:00

39 lines
1.3 KiB
Common Lisp

;; (require :lispbuilder-sdl)
(defun draw-noise (surface)
"draws noise on the surface. Returns the surface"
(let ((width (sdl:width surface))
(height (sdl:height surface))
(i-white (sdl:map-color sdl:*white* surface))
(i-black (sdl:map-color sdl:*black* surface)))
(sdl-base::with-pixel (s (sdl:fp surface))
(dotimes (h height)
(dotimes (w width)
(sdl-base::write-pixel s w h (if (zerop (random 2))
i-white i-black ))))))
surface)
(defun draw-fps (surface)
"draws fps text-info on surface. Returns surface"
(sdl:with-surface (s surface)
(sdl:draw-string-solid-* (format nil "FPS: ~,3f" (sdl:average-fps))
20 20 :surface s :color sdl:*magenta*)))
(defun main ()
"main function, initializes the library and creates de display window"
(setf *random-state* (make-random-state))
(sdl:with-init (SDL:SDL-INIT-VIDEO SDL:SDL-INIT-TIMER)
(let ((main-window (sdl:window 320 240
:title-caption "noise_sdl.lisp"
:bpp 8
:flags (logior SDL:SDL-DOUBLEBUF SDL:SDL-HW-SURFACE)
:fps (make-instance 'sdl:fps-unlocked))))
(sdl:initialise-default-font)
(sdl:with-events ()
(:idle ()
(sdl:update-display (draw-fps (draw-noise main-window))))
(:video-expose-event ()
(sdl:update-display))
(:quit-event () T)))))
(main)