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View Full Version : shader prob - white jaggies on transparent grate


clu
03-20-2003, 04:31 PM
Hey all

Here's a pic of a transparent grate shader I made that's having some anti-aliasing or some other issues. It has this ugly white, halo/jaggy effect around the edges where it becomes transparent:

http://www.jakekeating.com/pub/grate_problem/shot0001.jpg

Anyone know how to get rid of this? My shader code follows:


textures/colo/fence01_2sided
{
cull none
qer_editorimage textures/colo/fence01.tga
{
map $lightmap
alphaFunc GE128
}
{
map textures/colo/fence01
alphaFunc GE128
blendFunc GL_DST_COLOR GL_ZERO
rgbGen identity
}
}

My targa file is fine (no white things on edges), so I'm hoping theres a magic line of code I can add to feather the edges or something. Anyway, any help would be great.

-clu

Leslie Judge
03-20-2003, 04:42 PM
First of all I would delete the aplhaFunc from the lightmap stage.

I use a grate with the following shader code:
textures/twoofakind/floorgrate
{
qer_editorimage textures/doomgiver/floorgrate1
surfaceparm trans
surfaceparm nomarks
cull disable
{
map textures/doomgiver/floorgrate1
blendFunc GL_ONE GL_ONE_MINUS_SRC_ALPHA
rgbGen identity
}
{
map $lightmap
blendFunc GL_DST_COLOR GL_SRC_COLOR
}
}

Maybe this helps to figure out something.

clu
03-21-2003, 01:17 AM
Thanks for the response, Leslie. I don't know, maybe my alpha channel is messed up. I can't say I'm an expert with those. Here's what I get with your code:

http://www.jakekeating.com/pub/grate_problem/shot0002.jpg

If you're incredibly curious, I posted my targa file as well:

http://www.jakekeating.com/pub/grate_problem/fence01.tga

-clu

clu
03-21-2003, 03:11 AM
OK. I think I'm almost there. I used your same code again, Leslie. This time I re-did my targa. Used a layer mask to make the alpha channel, and somehow it now works (almost).

Now the only weird things are as follows:

1) The transparent areas of the grate appear slightly grey (instead of truley transparent): http://www.jakekeating.com/pub/grate_problem/shot0003.jpg

2) When looking through one grate to the other side, both grate textures seem to flicker a bit and kind of blink in and out.

By the way, I am using a fully caulked brush with one face textured with the shader.

-clu

Leslie Judge
03-21-2003, 12:18 PM
It always seemed a little weird how the game engine displays the transparent textures. I got your TGA, and I'll make a few test with it.