Rendering out lightmaps for walk-around models
polycounter lvl 10
Hi everyone, I'm currently working on an aircraft weapon component (missile) in Maya 2012 with the intention of bringing into a somewhat dated engine that does not support normal or specular maps - only diffuse. I have some details such as normal mapped rivets along my model that I need to bake out into a light map. I would like for as many details to catch specular highlights as possible so they aren't lost to shadows. So far, work is very slow and tedious, I'm finding that I need to use a lot of lights, even with a specialist baking tool like Turtle. Overexposed areas due to light source stacking is also becoming a real problem. Can anyone suggest any methods to improve my workflow? Admittedly, rendering is not my best subject with 3D so I could certainly use some advice. I have read there are some specialist programs just for rendering out turntable VR previews that may or may not facilitate what I need in a more expedient manner. Would any of them be worth looking into for my purposes? Thanks in advance.
Replies
What you could do is convert the normalmap into an ambient occlusion map, and multiply this into the diffuse.
Trying to bake specular highlights into a lightmap is going to be fruitless, because specular is view-angle-depenedant. It will look wrong when baked, because it won't move when the model moves.
Lots of lights do become a problem. The best solution is usually to use as few lights as possible. A skylight or domelight is a good first step for exterior lightmapping, combined with a directional/infinite light (the sun) and a bounce or two.
Sorry, I haven't used Maya enough to offer much help there. This might help though.
http://wiki.polycount.com/LightMap#More_Information
If it is static and mostly scene from one angle, you could bake specular just like they did for a lot of props in RAGE.