Working with vertex normals in Blender - how?

I’ve the issue with it in my games and I saw some devs were struggling with it across all kind of projects. The modular geometry will have issues on the split surfaces in game engines.

Here is a perfect example of what I am talking about:

I found this post on how the problem gets solved and someone wrote script for 3DS Max:

http://wiki.polycount.com/VertexNormal#GetVertNormalsFromFace_MAXScript

How can that issue be solved on Blender with the tools it has? Thanks.

The image you show appears to use averaged/smooth normals. Your best bet in blender is to mark edges “sharp” and using the edge split modifier, that way you get something akin to smoothing groups in 3DSmax. There’s no way to directly edit vertex normals in blender except in script, and even then blender will recalculate them all the time (e.g. when entering/exiting edit mode). Even your export script may or may not recalculate them. So yeah, this is a known problem especially for CAD data (which relies on custom normals) and to some degree games (which sometimes rely on hand-edited vertex normals)

I can’t do Edge Split because I have to actually split geometry and export a tilable piece of it, which gets tiles in the level editor or in-game. Or do you mean to mark Edges as Sharp, apply Edge Split and then export?

Yes, you would need to apply the edge split modifier on export (your exporter probably has an option for that)

Moved from “General Forums > Blender and CG Discussions” to “Support > Modeling”

motorsep, please post support threads in the proper forum.