PLY export vertex color issue

[yoli]

Hi, PLY export doesn't seem to export properly vertex colors. I am exporting from PhotoScan Standard 1.4.1 (on Windows) a 2 millions mesh with vertex colors in PLY format, trying to open it in ZBrush and Blender. In ZBrush, colors are wrong, in Blender, I don't see colors. If now I export the same mesh with vertex colors as FBX, I can see proper colors in both ZBrush and Blender.

[Alexey Pasumansky]

Hello yoli,

I've just tried to export a random model in PLY format (with about 3 millions faces), but am not observing the problem.

Can you post the screenshots of shaded view from PhotoScan and from MeshLab for that PLY and also specify the export parameters used (normals, binary encoding)?

[yoli]

Hi Alexey,

Here are some screens. I tried to export PLY as binary and non-binary, the result is the same. In MeshLab I cannot get the vertex colors (but I don't know this software well so I might not be doing the right thing). In Blender I cannot get the vertex colors either (but I can get them if I import an FBX). In ZBrush the colors are completely wrong (in a way it may be an endian ordering issue btw). Regarding ZBrush, I am using this plugin to import PLY with ZBrush 4R8.

Edit: if I import DAE file (generated by PhotoScan) into MeshLab, I can see the vertex colors. So definitely the PLY generated by PhotoScan has a problem regarding vertex colors.

Edit2: another test I made: export mesh as DAE from PhotoScan, open DAE mesh into MeshLab, export mesh as PLY from MeshLab, import PLY mesh into ZBrush : vertex color is proper. So this is another demonstration that the issue is coming from PhotoScan.

[Alexey Pasumansky]

Hello yoli,

Thanks for additional information.

I think we were able to reproduce this issue with PLY, so hopefully the fix will be implemented in 1.4.2 update.