Why extract a texture map?
Sculpting and subdividing models in Mudbox can produce models with very high polygon counts resulting in large file sizes. While you can easily export your models as either .fbx or .obj files for use in other 3D software and games applications, these software applications may not efficiently handle models with polygon counts in the range of tens of millions.
The recommended workflow is to extract a normal or displacement map (or both) that represents the high resolution surface(s) from Mudbox and export the texture maps so they can be applied to a simplified (low resolution) version of the model in another 3D application. As a result, the fine high resolution detail is maintained on a simpler version of the model.
The type of map you extract depends on your particular needs and production workflow. The UVs & Maps > Extract Texture Maps menu item lets you extract high resolution detail from a sculpted mesh in many image formats or in Ptex format. You can extract the following:
- The Transfer Paint Layers option lets you transfer multiple paint layers from one model to another, regardless of whether the models have different topology or UVs. For more information, see Extract Texture Maps properties.
- An ambient occlusion map is a shading effect that calculates the attenuation and occlusion of light between surface details and other objects in the scene. Mudbox can calculate this information as a high resolution image map and assign it as a paint layer to the selected target model to simulate a realistic shading effect. For more information, see Ambient occlusion maps overview.
- A vector displacement map provides both height and directional information for each pixel which provides the ability to displace vertices off-normal allowing users to faithfully recreate complex overlapping shapes. For more information, see Vector displacement maps overview.
- A displacement map represents the height difference between the two surfaces as a gray scale image. For more information, see Displacement maps overview.
- A normal map extracted in Mudbox represents the difference of the surface normals between the sculpted source model and the target model and represents these differences as a color map. For more information, see Normal maps overview.
For most texture extractions, the source and target meshes can be low and high resolution versions of the same mesh or even arbitrary meshes that have differing topology but suit the production pipeline requirements.
When extracting vector displacement maps, the meshes must either have the same base topology, or one mesh must be identical to a subdivided level of the other.
It is also possible to extract detail from 3D laser scans of a real model and produce a map that can be applied to a digital mesh that has UV texture coordinates at a lower resolution.