This mesh has texture colors which display correctly, but ComputeVertexColors doesn’t work: afterward when inspected in Grasshopper/DeconstructMesh there are no colors.
If I export as .ply with vertex colors it works: when I re-import that file the mesh is colored by vertex. So Rhino is able to associate the displayed colors with the mesh vertices, just ComputeVertexColors doesn’t do it.
I see this in current R7 and the R8 WIP.
Thanks,
-Bathsheba
0000000.zip (4.5 MB)
Hi Bathsheba - it seems to be related to the bitmap - other images or textures applied to the mesh reasult in vertex colors being assigned. And this image on other meshes fails.
@Bathsheba it seems a workaround is to bring in the texture to the texture panel, make a new Custom material with that texture in the color slot, assign the new material, then ComputeVertexColors.
-Pascal
I tried opening the image in Photoshop and re-saving as 8-bit PNG, 24-bit PNG, and JPG; all failed. Weird. It’s like Rhino doesn’t like the colors, even though it can plainly read them perfectly well.
I can’t seem to apply your workaround…I put an image in the texture panel, but when creating a custom material I don’t see an option to choose from those images, only to import a file which doesn’t seem to work.
For what it’s worth, the bad image is already present in the panel and there’s already a custom material with it that is marked “Legacy V4” which seems maybe old? 
Anyway thanks for looking. I have a lot of these, the images are generated in Python by PIL.Image.fromarray() mode ‘RGB’.
We also have an open ticket at the moment to resolve some inconsistent behaviors we’re seeing.
Thanks! My particular example still fails in 8.0.23276.13303.
Hi Bathsheba, I see that, thanks
-Pascal