[Bf-codereview] Remesh modifier (dual contouring) (issue 5491053)

[NicholasBishop at gmail.com]

Thanks for reviewing :)

Uploaded a new patch with some of the comments addressed. Also now
includes MOD_remesh.c, which I accidentally left out before.

Some notes:
You're right about the duplicate data in Projections.h and
IntegerGrid.h; turns out IntegerGrid.h isn't used anywhere in this code,
so removed it.

Changed the constant arrays defined in Projections.h to extern, and
moved their initialization into a new Projection.cpp file.

Trimmed down the memory allocator code a bit, only two classes there are
actually used. Didn't change the alloc/free calls to guardedalloc, but
it's a smaller change now if we prefer to do that.

As suggested, gave RemeshModifierMode explicit values and swapped the
'row.active' order in the UI file.

Regarding GPL headers and the eigen files: I added GPL headers to the
dualcon.h and dualcon_c_api.cpp files with myself as contributor; we
should also be safe adding GPL header with Tao Ju as contributor for
most of the dualcon intern code. However, the eigen files have a
different author, and we may not have permission to distribute it. (Went
back to old emails and found this concern was discussed then.) I'll look
into replacing this code with existing matrix code (possibly using the
Eigen3 lib.)

http://codereview.appspot.com/5491053/