Texture baking with 3Dsmax

Question

I'm struggling with a texture-baking process with 3DSmax software. I have a white 3D mesh with 2 image textures. I'm trying to get a diffusemap (see target_diffuse_map.jpg). To do this, I exectue the following steps:

1) Affect image-texture1 and image-texture2 to face1 and face2 of the objet.

2) Clone the object to get the white colors when baking texture.

3) unwrap UVM.

4) Rendering Texture to obtain the diffuse map.

5) Projection of the texture + white colors on the cloned object.

Please, find these steps on this small video I made: https://drive.google.com/file/d/1h4v2CrL8OCLwdeVtLmpQwD250cawgJpi/view

I obtain a bad sampled and weird diffuse map (please see obtained_diffuse_map.jpg). What I want is target_diffuse_map.jpg.

I'm I forgetting some steps?

Thank you for your help.

Answer 1

You need to either:

• Add a small amount of "Push" in the Projection Modifier
• Uncheck "Use Cage" in the Projection Options dialog, while setting a very small value for the offset

Projection Mapping works by casting rays from points on the cage towards corresponding model points on your mesh. You did not push the cage out at all, therefore rays are not well defined; rays are cast from a point toward a direction which is the exact same point. This causes numerical errors and z-fighting. The there needs to be some time amount of push so the "from" and "to" points of each ray are different giving them a well-defined direction to travel.

The second option, instead of using the cage defined in the projection modifier, is to use the offset method (you probably still need to apply projection modifier though). This method defines each rays as starting from a point defined by taking the model point of the mesh and moving outward by a fixed offset amount in the direction of the normal. The advantage is that for curved objects with large polygons, it produces less distortion because the system uses the smoothed shading normal at each point. The disadvantage you can't have different cage distances at different points of the model, for better control. Use this method for round wooden barrels and other simplistic objects with large, smooth curves.

Also, your situation is made difficult by having different parts of the model very close to each other (touching) and embedded within each other - namely how the mouth of the bottle is inside the cap and the cap it touching the base. For this case, it might make sense to break the objects apart after you have the overall UV mapping, run projection mapping separately on each one separately, and then combine the maps back together in an image editor.