How to bake lightmap to a simplified duplicate object? I am importing models from magicavoxel, and then lighting them in blender. I have a high-res model which contains all the materials (as vertex colors) and emitters.



It renders nicely in cycles:



I've worked out how to duplicate the mesh, remove materials and "remove doubles" then "limited dissolve" to create a low poly version of the mesh.



However - I can't work out how to bake from the high res mesh to the low res mesh. I have tried going to "cycles settings" on the low poly standin and disabling "Camera" from Ray Visibility - but when I bake the texture - I just get a big green smudge, I can't see any of the vertex colors baked into the standin:



Can someone explain to me how I should use cycles to bake the lightmap onto the low-poly duplicate?
Limited dissolve with default settings, in most cases can destroy the UV map.
To avoid that you need to enable UVs, in the operator panel in Delimit section.