PBR maskmap workflow, Substance painter to Unreal engine

When you use maskmaps for the textures you’re essentially combining the roughness-, ambient occlusion- and metallic maps into one single texture map, which practically means that you’ve reduced your drawcalls by two for every material in your scene. It might not sound like a lot, but concider a situation where you have a scene with hundreds of assets with respective materials, those drawcalls add up. Setting up a maskmap workflow from the beginning is rational and optimal when working with the hard limits that VR imposes on game dev.

Rational UV-mapping

Making the most out of your UV-space is super important to maintain quality while still making highly optimized assets. Polygons that are never in view and don’t affect lightbaking should always be removed, in this case the backside of the painting was removed to not waste precious UV space. Parts of the model that are liable to be closely scrutinized should be awarded a larger part of the UV-space while parts of the mesh that are less important should be smaller. In the case of a character model, one could perhaps expect to let the head occupy as much as half of the UV space while the rest of the body would have to make due with the leftovers.

Texture atlases

In the case of for example tileable materials, one smart way way to optimize the scene for maximum quality is to split the model - in this case the floor - into perfect squares. When UV-mapping, all individual squares are cut out and places on top of each other in the UV-space. So instead of having to have a 16K-texture projected over the whole floor to avoid pixelation and bad quality, you can just project a 2K-texture and have it tile beautifully!