To deal with the problem I experienced in this thread (Blender’s tangents are generated differently from Away3D’s causing hard seams on all models with normal maps), I found a patch for Blender which allows access via the Python API to Blender’s own tangents. I then proceeded to create a custom format which exported all 3D data (verts, normals, tangents, UVs, indices), and wrote an Away3D parser for it, following Fabrice’s advice from this post.

For the vertex animation, I exported a full copy of the model at every Blender keyframe (verts, normals, tangents, UVs, indices), and used that to create the Geometry which gets used for each frame in a VertexClipNode. Yes, it’s overkill. I don’t care. I want accuracy.

The model loads and animates. The seams are gone. However, though the animation is correct, at each keyframe, the lighting jumps. I assume this is because the vertex normals and tangents don’t interpolate like the vertices do. Is that correct? If that’s correct and that’s how it’s supposed to be, what is the standard way to not make the lighting jump? Just copy the normals and tangents from the first frame to all the rest?

Link: Lighting jumps at keyframes SWF

Help me out here, devs. I’m paving a currently nonexistent road between Blender and Away3D.