How do I bake a projection to a texture file?

[TomRaynor]

Could anyone tell me how I can take a UV'd object that has a material applied with a camera projection and bake that to a 2d texture file using the UV space of the object?

(similar to Maya's "Lighting/Rendering->Batch Bake (mental ray)" menu option)

Many thanks!

[Akabane]

If I remember correctly you can import a geometry in a COPS environment, that will read the UVs and material information, so you should simply be able to save out a file from COPS and it will render out the correct texture to file

[akrilcg]

if you just want to bake out textures based on the UV then you can use Mantra -> Render -> UV Render Object.

UV Render object

The name of the object to be rendered in UV space. Mantra is able to render an object in UV space rather than 3D space. Only one object may be rendered in UV space.

[TomRaynor]

Thanks very much guys.

[TomRaynor]

Still can't seem to quite get it to work how I want. Just to clarify I want to project a texture onto an object. Then give it some completely different uv's to the uvs that you get from camera projecting onto an object. Then bake out the texture as it was projected onto the object into the new UV layout.

I have attached a scene to try and illustrate what I mean.

Thanks,

Tom

bakeProjectionToNewUVs_v01.hip

[TomRaynor]

Ah found a solution. It seems I have to make two sets of uvs, one for the projection and one for the render object to use to render out the texture.

Works well though.

Any ideas for how it could be done better would be most welcome.

Solution attached.

Cheers!

bakeProjectionToNewUVs_v02.hip

[gui]

I think your workflow is the correct one. Note that you can use an uvlayer ("layer" sop, set layer to 2), after the material1, then just append an uvunwrap, easier and cleaner.

Edited February 15, 2013 by gui

[symek]

Alternatively you may project a texture from a light, possibly surface shader with an additional illuminance() loop is required.

More generally, you may project uv from a light during render time (if for any reason you don't want to touch geometry). Albeit more involving this method introduces new possibilities. Take also a look on LayerSOP as it simplifies work with uvs sets. The attached example contains second take, which overwrites an object material, and that's pretty much it.

hth,

skk.

bakeProjectionToNewUVs_skk.hip

[gui]

Thanks for the info SYmek, didn´t know about using lights to project uv´s!