Hi
Thanks gabor, this works fine. Although i get only 48 FPS, which seems
quite low for a simple scene like this and i usually get much higher
framerates with more complicated fullscreen shaders and rendering to
framebuffer objects in OpenGL.
It seems that even (build-pixels 1 1 #t) limits the framerate to about
48 FPS on my laptop with nothing else going on. Quite mysterious.
Since postprocessing is (or should be) a common task and since even
without any actual geometry as input nice things can be done on a
fullscreen quad by a shader (raymarching etc.), we might want to
integrate this as a feature into fluxus.
Maybe a simple wrapper like
(every-frame
(with-postprocessing (shader-code f)
(draw-cube))
would be nice. maybe we could even nest those to obtain multiple
passes? So we don't have to bother with planes, vertex shader, screen
resolution, and camera transformations when we just want every pixel
touched by a fragment shader once.
Concerning the power-of-two-issue, probably the best method would be to
check for GL_ARB_texture_non_power_of_two to be present - only if it is
not, round up to the next POT.
Kas, thanks for the thoughts. I feel that preparing code hurts the
performance, even for simple shaders.
cheers,
Johann
