We now initialize iter.valid as true as part of the main iterator (and manually
when using via Python). And we don't even bother setting iter->current to NULL
if it's invalid. Let's stick to using iter->valid only.
The legacy algorithm only considers two adjacent points when computing
the bezier handles, which cannot produce satisfactory results. Animators
are often forced to manually adjust all curves.
The new approach instead solves a system of equations to trace a cubic spline
with continuous second derivative through the whole segment of auto points,
delimited at ends by keyframes with handles set by other requirements.
This algorithm also adjusts Vector handles that face ordinary bezier keyframes
to achieve zero acceleration at the Vector keyframe, instead of simply pointing
it at the adjacent point.
Original idea and implementation by Benoit Bolsee <benoit.bolsee@online.be>;
code mostly rewritten to improve code clarity and extensibility.
Reviewers: aligorith
Differential Revision: https://developer.blender.org/D2884
Recent addition of 'reinsert' didn't match logic for ghash API.
Rename to BLI_heap_node_value_update,
also add BLI_heap_insert_or_update since it's a common operation.
The single byte version of hash_data was casting from unsigned char
instead of signed.
This didn't cause any errors since the result of each aren't compared.
Even so, better keep them matching.
Was using an edge hash for triangle -> edge lookups,
updating triangle indices for each edge-rotation.
Replace this with half-edge which can rotate edges much more simply,
writing triangles back once the solution has been calculated.
Gives ~33% speedup in own tests.
Notes:
- Changes in paint_vertex.c were simple to merge, mainly related on passing
evaluation context.
- Conflicts in EditDM and drawmesh.c are solved using code from blender2.8
branch. Those areas are deprecated and not to be used in final release.
However, it's possible that some reference code from master is lost, so
keep attention when adding alpha support for vertex painting.
