PDA

View Full Version : Alpha vs Texture Mask



legacy-Dark_Spectre
07-17-2003, 09:39 PM
Are there any advantages to using alpha channels as opposed to a mask texture, or vice versa? It would seem to me that there's little difference, which makes me wonder why they include both of these options.

legacy-Bonehed316
07-18-2003, 10:48 AM
texture mask? like a self illumination mask in a shader? actually, they are the same. the self illuminationmask slots use the alpha channel of the given texture, and have nothing to do with the RGB channels.

as far as "mask" tag when importing, i dunno. i dont think ive ever used that, but i think its the same thing.

legacy-Fordy
07-18-2003, 11:22 AM
I think that a masked texture uses the first colour in the palette as the mask colour (usually black but can be any colour) where as an alpha channel can have varying degrees or transparency without affecting the RGB channels.

Angel_Mapper
07-18-2003, 01:10 PM
In Face3 they use a lightmap as a mask in a combiner on the asteroid meshes, to get the fade between different textures. It's just another way to get that effect if you don't want to use Vertex Colors.

legacy-Dark_Spectre
07-22-2003, 08:06 AM
Well, at UDN they said to use a masked texture as opposed to an alpha texture, because alpha textures require sorting. This bothered me a bit, because until now I've always used alpha textures. However alpha channels do seem to be far more powerful, you just have to set up your sorting properly so you don't get artifacts.

legacy-Bonehed316
07-22-2003, 08:22 AM
you can disable sorting :D not that it does anything good, but you can!