When importing meshes with vertex colors, we will now supply them to the
simplifier as attributes with weight=1 (in addition to normals). This will
guide the simplification to preserve regions where vertex colors change.
For this change to take full effect, it is also necessary to respect the
full error when selecting LODs; this change does not do that yet, so there
are going to still be cases where vertex colors change abruptly during LOD
switch in a visible manner.
Arseny Kapoulkine
9a8348cc2c