Texture baking help....Please

[ra5946]

Hello all

I was wondering if anyone in here might be an expert on 'render to texture' for 3D Max (version 8 in case that matters). I have a rather large house that uses about 12 different textures. Several walls and roof sides are really low in poly so vertex painting does not work so well.
I really love the shadow a skylight gives and I would like to "bake" the whole thing. I've done baking before but with much smaller objects and it's turned out quite nice. This house however is not retaining the same uv coordinates. It almost seems the model is scaled just a little larger after rendering so it just doesn't quite fit. The channels are correct and a new unwrap modifier screws the whole thing up, so I'm at a loss. I've researched several tutorials on the web, but none really seem to address the issue. I would appreciate any insight you might have on my problem.

Thank you

[nick_op]

Check out this link. That's the method I use to bake all my Ambient Occlusion (shadow) maps, works really well.

Max 8 might have a 'proper' method for doing ambient occlusion though (bouncing photons off the model with mental ray or something like that). I'd recommend looking to see if any of the tutorials that come with Max mention Ambient Occlusion, if not, try googling it.

[ra5946]

Thanks Nick, I'll check that out now. I was rendering the "complete" map. Why do you you only do the shadow?

Side note- My above issue was just a visual rendering problem in the max scene. When I exported the "screwed" up looking texturing job as a nif, it looked just fine in nifscope and in game. The only thing now is, even a rendered texture of 2048x2048 still is a bit blurry. How big is too big in terms of texture size? If this model was rendered without baking it has 15 different textures (all 512x512) plus their corresponding
normal maps. What is faster for the game to process, 1 huge map and normal map or a bunch or smaller ones?

[nick_op]

Originally posted by ra5946
Thanks Nick, I'll check that out now. I was rendering the "complete" map. Why do you you only do the shadow?

I've found using render to texture can often decrease the quality of a texture, so that's one reason I only do the bits that I think are necessary. Secondly, having the AO map on a seperate layer in Photoshop allows me to fix anything that might be wrong with it and tweak it as I see fit. Just use the 'Multiply' blending mode to overlay it onto your texture properly.

Also, it can be handy to have the AO map available when creating the specular map, to keep certain areas less shiny.

Side note- My above issue was just a visual rendering problem in the max scene. When I exported the "screwed" up looking texturing job as a nif, it looked just fine in nifscope and in game. The only thing now is, even a rendered texture of 2048x2048 still is a bit blurry. How big is too big in terms of texture size? If this model was rendered without baking it has 15 different textures (all 512x512) plus their corresponding
normal maps. What is faster for the game to process, 1 huge map and normal map or a bunch or smaller ones?

2048x2048 is 16 times bigger than a 512x512 texture, so using the 15 seperate textures is probably very slightly faster in that it uses less video memory. However, loading only a single texture may be faster than loading 15 different ones. There's probably not much in it.

I find it hard to believe that you'd need that many textures, though, or why they'd all need to be so big. I also can't imagine that rendering them all to one texture would create a usable map, but I've not experimiented with it that much.

[ra5946]

Thanks again. I guess this model should really be seperated into 4 parts. Three different structures with their own unique look (different roof,floors and walls) that why all the textures.

Cool technique with the shadow, but I suppose I would have to re UVW map my model to fit the new uv'd shadow map if I didn't render to texture the whole thing huh...



Thanks for all the help