26th May 2010, 05:28 PM | #19 | |
Senior Member
Professional user
Join Date: Mar 2005
Location: Phoenix, AZ
Posts: 917
|
Re: PLUGIN: Render to Texture: Light Maps, Normal Maps, AO
Quote:
The first set of texture coordinates is for the diffuse map, and is as you describe: overlapping as much as possible to use texture space as efficiently as possible. The second set of texture coordinates is specific to the lightmap. It's a unique atlas, and the lightmaps are *extremely* low-resolution. It's not uncommon to pack an entire scene onto a single 1024 lightmap, or small 32x32 or 64x64 textures for individual objects. Shadows are normally a little blurry anyway, so the maps can be pretty tiny and still look great. This keeps this method pretty efficient even though it uses more UV space. AC3D only supports a single set of texture coordinates for a model so if you're building models for a game, you'll want to create two versions of the model file and combine them in your export utility. [Multi-coordinates is definitely on my wish list :-) ] If you're fixed function, keep them as separate models and arrange it as a second pass. e.g. Render the first model as usual, then render the second model with alpha blending and a tiny z-buffer offset to blend the shadows in. |
|
|
|