2010-09-17, 05:13 PM
I'd be careful about "baking" in light. I'm not sure if by "UV itself" Todd means editing the texture, or "vertex painting" ... I thought BTW before that Som used per vertex colours to do transparency and shading in the objects, which would've been interesting. But it seems that material properties are used instead, which are pretty much uniform across a mesh / submesh.
When adding shadows directly to a texture in general you only want to do it (if at all) inside crevices / places which receive less light from all directions. If you shadow one side of the object that makes it useless in any kind of lighting scenario. Som's assets all follow "dirt mapping" rules, ie. the places which would tend to gather dirt (are less accessible) are shaded darker. Edited: I actually don't know if it's called dirt because it's the regions where it's harder to get dirt out, or the regions where dust would more likely collect. I feel stupid saying it anyway. And another thing to consider is textures are not always applied to the same area of a mesh, so baking in light can limit the applicability of a texture as well.
In a nice lighting setup you'd have an extra texture that would have info like specular / albedo / "dirt" I think. Specular says what part of the textures are "metalic", eg. produce a specular reflection. Albedo says what is the diffuse reflectivity of the texel. And dirt is basically how many photons are likely to gather in this area. So like on a suit of armor the metal areas would be more specular. The leather area's would have less albedo. And the arm pits say would have more (or less??) "dirt". So then even with vertex lighting you'd see per pixel lighting qualities without paying for per pixel lighting (I will definitely be working on some tech that will make this possible over the next few months, though it's not why I'm actually doing that work)
PS: The reason that kind of grass looks so bad is it's just trampled down flat. It always looks really bad in a game. I think most games are just content to make the ground vaguely green. Even the best games I can think of. I may actually do a review of some games / see how they do grass. Unfortunately grass is not something easy to do. Without any kind of LOD framework it's best just to go green I think, which the occasional tufts here/there.
When adding shadows directly to a texture in general you only want to do it (if at all) inside crevices / places which receive less light from all directions. If you shadow one side of the object that makes it useless in any kind of lighting scenario. Som's assets all follow "dirt mapping" rules, ie. the places which would tend to gather dirt (are less accessible) are shaded darker. Edited: I actually don't know if it's called dirt because it's the regions where it's harder to get dirt out, or the regions where dust would more likely collect. I feel stupid saying it anyway. And another thing to consider is textures are not always applied to the same area of a mesh, so baking in light can limit the applicability of a texture as well.
In a nice lighting setup you'd have an extra texture that would have info like specular / albedo / "dirt" I think. Specular says what part of the textures are "metalic", eg. produce a specular reflection. Albedo says what is the diffuse reflectivity of the texel. And dirt is basically how many photons are likely to gather in this area. So like on a suit of armor the metal areas would be more specular. The leather area's would have less albedo. And the arm pits say would have more (or less??) "dirt". So then even with vertex lighting you'd see per pixel lighting qualities without paying for per pixel lighting (I will definitely be working on some tech that will make this possible over the next few months, though it's not why I'm actually doing that work)
PS: The reason that kind of grass looks so bad is it's just trampled down flat. It always looks really bad in a game. I think most games are just content to make the ground vaguely green. Even the best games I can think of. I may actually do a review of some games / see how they do grass. Unfortunately grass is not something easy to do. Without any kind of LOD framework it's best just to go green I think, which the occasional tufts here/there.