Adds support for vertex colors to OBJ I/O.
Importer:
- Supports both "xyzrgb" and "MRGB" vertex color formats.
- Whenever vertex color is present in the file for a model, it is
imported and a Color attribute is created (per-vertex, full float
color data type). Color coming from the file is assumed to be sRGB,
and is converted to linear upon import.
Exporter:
- Option to export the vertex colors. Defaults to "off", since not
all 3rd party software supports vertex colors.
- When the option is "on", if a mesh has a color attribute layer,
the active one is exported in "xyzrgb" form. If the mesh has
per-face-corner colors, they are averaged on the vertices.
Colors are converted from linear to sRGB upon export.
Reviewed By: Howard Trickey
Differential Revision: https://developer.blender.org/D15159
1b4f35f6a5