Was using pointer hashing when the keys are in fact uint's.
Since they're well distributed from the rangetree,
no need to do bit-shifting tricks. just use int as hash.
Gives ~8% speedup in own tests.
When the multisegment profile joins two unbeveled edges, all in the same
plane, users desire that rather than the current behavior of linear
interpolation between those edges, the profile should curve.
This changes behavior to do that. The old behavior can be obtained
by setting the profile parameter to 0.25, if desired.
Face islands furthest faces could face towards the center point when connected to sharp edges.
Now check the furthest edge of the furthest face, to test for face winding.
`CustomData_bmesh_interp_n` was expecting the 'dest' arg not to have its offset applied.
This was a bit confusing since the source args have it applied,
and in some cases we only have the destination with the offset.
This ensures slide with `Correct UVs` enabled, keeps UV's (any loop custom-data) contiguous.
Adds 2 key functions `BM_vert_loop_groups_data_layer_create` and `BM_vert_loop_groups_data_layer_merge`
They work by collecting matching loop custom-data around the vertices loop-fan,
and merging the custom-data after edits are made.
Thanks to @mont29 for review!
Error in custom split normals work, non-autosmooth normals != vertex normals!
Loops from flat faces shall take normal of their face, not their vertex.
Tsst...
This is the core code for it, tools (datatransfer and modifier) will come in next commits).
RNA api is already there, though.
See the code for details, but basically, we define, for each 'smooth fan'
(which is a set of adjacent loops around a same vertex that are smooth, i.e. have a single same normal),
a 'loop normal space' (or lnor space), using auto-computed normal and relevant edges, and store
custom normal as two angular factors inside that space. This allows to have custom normals
'following' deformations of the geometry, and to only save two shorts per loop in new clnor CDLayer.
Normal manipulation (editing, mixing, interpolating, etc.) shall always happen with plain 3D vectors normals,
and be converted back into storage format at the end.
Clnor computation has also been threaded (at least for Mesh case, not for BMesh), since the process can
be rather heavy with high poly meshes.
Also, bumping subversion, and fix mess in 2.70 versioning code.
