The .ply Writer behavior is incorrect
In different usecases, the ply writer exposed by paraview has an non-standard behavior and is more close to what an exporter would do.
Consider the folowing usecase :
- open SmallSubset.vtk, it contains an unsigned char array already usable as RGB color
- Show it in a Render View, uncheck MapScalars, correct colors appears
- Save as a .ply, check "Save Coloring"
- Resulting file contain incorrect color, as if MapScalars was checked, this is a (usability) bug.
Consider the folowing usecase :
- open SmallSubset.vtk, it contains an unsigned char array already usable as RGB color
- Show it in a SpreadsheetView
- Save as a .ply, check "Save Coloring"
- Resulting file does not contains any color, this is a limitation.
A suggestion would be, to work around the second part, that when using SaveColoring option, user can choose between extracting current active view visible or specifying which array to color with.
Also, I'm not really convinced by the folowing usecase :
- Open any .ply file containing coloring, Apply
- Save as a new .ply file, check "Save Coloring"
- New file is different than initial file.