Next, I'll take a break from the navigation, and I'll add decal support to the level editor. My engine has fairly advanced support for decals right now. I am using a variant on deferred shading, where you composite your diffuse textures first, including any terrain layers, decals like scorch marks, dirt, etc., then composite your tangent space normal maps, then once all is composited, lighting & shadows are applied. This has the advantage that decals are correctly lit, shadowed and fogged, including bump mapping.
Right now decals are only applied in the engine dynamically, when a laser bolt hits a wall or floor or other static obstacle. My plan is to use decals to spice up the levels as well. I will add the ability to apply decals to any static geometry, which will be useful for adding scratch marks, scorch marks to represent an earlier battle, cracks, blood, dirt, and even carved writing, murals, and bas-relief.
The decals can be diffuse, normal map, or both. Applying just a normal map decal will be a great way to make the stone walls & floors look carved.
Here an older shot of the level editor, and the in-game level, showing some scorch-mark decals.
