Again on tangents for multi-material meshes
Tangent calculation is now done in a single pass for all the
geometries of the current LOD. The vertices on edges between
different materials are listed in more geometries, so doing
tangents one for geometry results in overwriting and wrong
tangent values.
This should prevent "Overwriting X tangents" warnings.
Prevent memory crashes in the Editor
Sometimes the filewatcher reports a changed file when
its writing is not completed yet. This causes an out of
memory exception.
To prevent this try to write the files in a single API
call: the files are build in memory and written using
an 1Mb buffer.