texture baking onto vertex colors

Hi all, I’m new to the forum and to 3d modeling in general, I know what I want to do, but I’m not sure I’m using the correct terms.

I need to create terrain models to use them in a real time visualization, I can’t use large textures, so I would like to color the vertices of these models from a landsat image (obviously the models will have enough vertices to produce a decent result).
First: is this technique called “light baking”? or “texture baking”? or “vertex color baking”?
Second: I asked in many other application-specific forums on how to do this with that package, it seems that the ability to assign vertex colors from a bitmap is quite uncommon! So far I’ve found that only Lightwave and 3ds Max can do that, but I was looking for something much cheaper. Can Blender bake a texture to vertex colors? can you suggest a specific tutorial on this subject? in the documentation I found nothing about it, and in the tutorials I’ve found how to bake vertex colors onto a texture (the opposite of what I want to do).
Otherwise I was suggested to look at XSI for its Ultimapper tool, which can do what I was looking for, can you confirm this is the right tool? I got no answers on XSI forum. Any other suggestions regarding 3d modeling packages with this feature?

Here’s a link to a movie made from Lightwave, in the first part of the movie you can see what I’m looking for: the guy takes a shape, it applies a bitmap to the vertex colors and then subdivides the mesh getting very close to the original bitmap drawing. In lightwave this is called “textured point”.

Do you have other suggestion on how to obtain this result? I have to use as much real geometry as possible, because the point of view will be very close to the terrain.
Thanks
Marco

here is how I did it, I had to start with a cube or a plane,and the face you are using faces forward (I mean on Z). set the texture in the materials to the image. then go to viewport mode: shaded. Set vcol paint and shadeless in the material. go to edit buttons, press make vertexcolors.
It will look better with a texture instead I think.

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Ok, many thanks! :slight_smile:
Marco

hi, you have to export your texture using the texture baker. There’s another step too, but I don’t know if you can do it with this version, because there’s a problem with the UV coord updating, they may have fixed it this last version, but here’s the deal: ( using a version that updates properly ) Uv map your low poly model, then, make a copy, subsurface it, convert the subsurf modifier to a mesh ( apply button or ctrl+c ) then bake the vertex colors ( as just described in the above post ) and export using the texture baker ( in the UV menu )

Ok thanks :slight_smile:
May I ask if there’s a complete tutorial on this section of the program? I’m new to Blender…

I don’t think there is, but you might try searching the python and plugins forum for info on the texture baker. It’s a script. ordinarilly you call it from the UV pop-up menu in the UV window. It would be nice if someone made a tut on making light maps though, and when I get finished with my current projects I’ll make a good one if nobody else has by then. If you have any specific questions though, feel free to ask, and I’ll try to answer them.

I don’t understand how this is any different to mapping an image onto the mesh? And isn’t it just as lores?

well, he wants to bake his shadows and vertex colors to an image file, so, if you do that in low poly, the result is not going to look as good as if you do it in high poly. but if you take a light map you made with a denser mesh, and apply it to a low poly mesh, it will look more similar to the high poly mesh except around the edges.

Actually I’ll have to try with as many polygons as possible. My mesh will be an imported terrain file, for the final result to be decent I’ll have to keep it’s geometry as it comes.

Modron, I have some problems.
I think I correctly mapped an image onto a mesh. However the image that is used in the uv mapping dialog is not considered the image texture right? I have to add a texture in order to use the make vertex colors button.
After doing that I run the texture baker, which opens a render window :confused:
In any case after exporting the mesh into .3ds or .x the vertex colors are lost!
Any suggestion?

may help :
http://jmsoler.free.fr/didacticiel/blender/tutor/cpl_mesh3d2uv2d_en.htm#Enregistrerunemappederadiosite

I took a look at the tutorial, I think I wrongly called what I was looking for as baking, actually I would like to get rid of all the textures, this script on the same site is probably more suited for my needs :). The problem again is that vertex colors information is lost when exporting the file! That’s why now the problem is no more how to create vertex colors but how to export them, anyone knows an exporter which preserves vertex color information?

does 3ds or .x support vertex colors in the first place? If so you probably have to modify the scripts to add that feature if it is not there.

As far as I know .x does support vertex colors, for many other applications rely upon this format as an exchange medium.

Just to let you know, I found the way to do the vertex baking: Ultimate Unwrap 3d has a function to convert the texture onto vertex colors and export them in .x format. Probably the .x exporter in Blender doesn’t include vertex colors in the file. Thanks to everyone for their help anyway :slight_smile:
Ciao