View Full Version : clamp_to_border

07-02-2004, 03:34 AM
I work on a project and I use the extension GL_CLAMP_BORDER because I apply a texture smaller than the region where it is applied, and I need the uncovered region to be transparent.
On my desktop computer, all goes fine ( 140FPS average), but when I launch on my laptop, I have 0,2 frames per secondes. If I turn-off CLAMP_BORDER, I have a 140 framerate.
My laptop GPU is a Geforce4 MX 420.
Maybe GL_CLAMP_BORDER is not supported by this card.

So is ther a way to have the same results on my textures witout GL_GLAMP_BORDER ?

07-02-2004, 03:45 AM
Another way would be to use GL_CLAMP_TO_EDGE and set the alpha of the edge texels to 0 so that alpha test kills them. You loose two texels in each direction, but get full hardware acceleration.

07-02-2004, 03:51 AM
ok, but I can't edit my textures, because I work on an 2D animation software, and my textures are drawings, and I can't retouch all frames(36000 frames by episods )

07-02-2004, 06:03 AM
You can change the alpha programmatically before download of the texture, not on the original and by hand.
Do you actually use texture borders or only the texture border color?
I don't expect that to make a difference on the GF4MX though.
If it falls back to software rendering, check if not using a hardware pixelformat on those works better.
The other option is to require a minimum hardware equipment above that of your laptop.
I can't say if there's another solution with the current informations of "a 2D animation program".

07-02-2004, 05:03 PM
Depending on your shading requirements, maybe you can use multitexturing with your "image" in the first texture unit and a small 2D alpha cutoff in the second texture unit.