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Another thread to discuss about the 4th parameter in the (build-pixels) function.<BR>
<BR>
I do realize the point for a ffgl chaining but I can't figure out the feedback goal.<BR>
Taking the supplied fluxus example : pixels-feedback.scm<BR>
<BR>
(clear)<BR>
<BR>
(scale (vector 20 15 1))<BR>
<BR>
(define p (build-pixels 512 512 #t 2))<BR>
<BR>
(define frame 0)<BR>
<BR>
(every-frame<BR>
(let ([tex (pixels->texture p frame)]<BR>
[ptex (pixels->texture p (bitwise-xor frame 1))])<BR>
(with-primitive p<BR>
(pixels-render-to tex)<BR>
(pixels-display tex))<BR>
(with-pixels-renderer p<BR>
(clear-colour 1)<BR>
(with-state<BR>
(texture ptex)<BR>
(rotate (vector (* 60 (time)) 45 0))<BR>
(scale 6)<BR>
(draw-cube)))<BR>
(set! frame (bitwise-xor frame 1))))<BR>
<BR>
I don't see the goal of the alternating frame variable value<BR>
and why don't shorten this in this, using only one texture:<BR>
<BR>
(clear)<BR>
<BR>
(scale (vector 20 15 1))<BR>
<BR>
(define p (build-pixels 512 512 #t 1))<BR>
<BR>
(define frame 0)<BR>
<BR>
(every-frame<BR>
(let ([tex (pixels->texture p frame)])<BR>
(with-primitive p<BR>
(pixels-render-to tex)<BR>
(pixels-display tex))<BR>
(with-pixels-renderer p<BR>
(clear-colour 1)<BR>
(with-state<BR>
(texture <B>tex</B>)<BR>
(rotate (vector (* 60 (time)) 45 0))<BR>
(scale 6)<BR>
(draw-cube)))))<BR>
<BR>
The other Gabor example "pixels.scm" seems to me quite confusing too with this balanced frame variable.<BR>
<BR>
That was my first questioning<BR>
I read in the mailing list, the main goal was to avoid multiple pixels primitives.<BR>
My goal is to build a pixels renderer with a pixels or texture mask what I did with to pixels renderer and a multitextured plane playing with blending parameters.<BR>
You'll find it in attachement in "multitexture-pixels.scm".<BR>
<BR>
But can I use the different pixels primitives textures to do sort of multitexturing, or I'm misunderstanding this.<BR>
<BR>
Thanks for any explanations.<BR>
<BR>
On an other note, there is no documentation in the helpmap on the (pixels-render-to ) and (pixels-display ) functions, and the 4th (build-pixels) parameter.<BR>
I'll be happy to translate but I prefer to let you explain these things. ;-)<BR>
<BR>
<BR>
best,<BR>
Ted
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