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gggggllll
05-28-2003, 04:41 AM
my video card - geforcefx5200 - does not support gl_ext_paletted_texture.

how can i use 256 colored bitmap for texture ?

soda
05-28-2003, 04:47 AM
Originally posted by gggggllll:
my video card - geforcefx5200 - does not support gl_ext_paletted_texture.

how can i use 256 colored bitmap for texture ?

>>> I don't know the answer but I'm interested too by this problem !

If you find something please post it in the forum !

gggggllll
05-28-2003, 04:55 AM
ok!

maybe there's answer in glPixelMap functions, but it doesn't work at all!!

KlausE
05-28-2003, 06:16 AM
You have to use some fragment program extension of ATI or NVidia (texture_shader, fragment_program, etc.) that supports dependent texture lookups.

Store your color table in a 1D(1xn 2D) texture. Configure the texture units:
1. Lookup into the 2D/3D texture containing the scalar values
2. Dependent lookup (eg. dependent_ar) into the texture containing your color table.

This way, the scalar gets converted to a texture coordinate for the subsequent lookup into the transfer function.

heath
05-28-2003, 07:33 AM
On Linux with 43.63 I'm almost certain it was still working for me. I suppose you're using Windows. Which drivers are you using.

In response to your original question however, a simple solution would be to simply convert it to 24 bit, and use texture compression. It'll come out about the same size in VRAM.

If you want to play games with its palette then in the longterm you'll have to take the approach previously mentioned.

Hope this helps,

Heath.

[This message has been edited by heath (edited 05-28-2003).]

[This message has been edited by heath (edited 05-28-2003).]

soda
05-28-2003, 03:17 PM
Hi,

In my case I want to have a solution working with ALL recent graphic cards, so ATI or NVIDIA extensions will not solve the problem

I don't understand why paletted textures are no more supported !

So I need to change quickly color of each pixel of a texture, that's why I tryed to use GL_COLOR_TABLE (see post gl_colorTableExt does not work for me)

I hope that it's possible http://192.48.159.181/discussion_boards/ubb/wink.gif

soda
06-04-2003, 09:29 AM
Originally posted by gggggllll:
my video card - geforcefx5200 - does not support gl_ext_paletted_texture.

how can i use 256 colored bitmap for texture ?

>>> did you find a solution ?

Coriolis
06-04-2003, 11:33 AM
Originally posted by soda:
Hi,

In my case I want to have a solution working with ALL recent graphic cards, so ATI or NVIDIA extensions will not solve the problem

I don't understand why paletted textures are no more supported !

So I need to change quickly color of each pixel of a texture, that's why I tryed to use GL_COLOR_TABLE (see post gl_colorTableExt does not work for me)

I hope that it's possible http://192.48.159.181/discussion_boards/ubb/wink.gif

If you want to work on all cards, then there is no time in the past few years that EXT_paletted_texture would have been an acceptable solution... ATI and Matrox have never supported it.

V-man
06-05-2003, 03:39 AM
It's not in the core of OpenGL so of course, you have to have alternate solution for this extension! Even the MS D3D driver doesn't have this extension.