(please forgive the typo in my title)
Last week we were diagnosing some outsourced art in our engine, and are seeing a frequent issue that may sound familiar to some:
looks fine in 3DS Max/Maya, but the exported normals are whacked in the engine.
It took us a bit of diagnosis to determine the vertex normals were somehow messed up.
But as the TA here I was faced with a lack of understanding: I didn’t know why they were messed up on a technical level, or what DCC operation (filpping? unifying? smooth group? hard soft edges?) to recommend for a solution.
In fact I can’t say I understand fundamentally what such operations actually do in a technical sense. I gather form previous reading that to a game engine, there really are only vertex normals, and that edge and face normals are just compouds of vertex normals (please correct me of that’s not right,) but that’s about as far as my understanding goes.
So, I’m looking to strengthen my understanding of all things normal related. Are there any good articles, old TAO or CGTalk wikis, posts ,or even books, I should check out?