Since data transfer when called from this tool has reversed behavior (it transfers **towards**
active object, as previous tool), we have to also reverse source/destination layers selection options.
Also fix 'reverse' option being saved, otherwise calling regular operator after 'transfer weights'
would stay in reverse mode, ugly!
This is likely weak design, but allows people to change several settings without having to wait
several tenth of seconds each time, when e.g. transferring UVs between heavy geometries.
This allows to match and transfer data between two meshes with similar shape but complete arbitrary different transform.
Note that the result will be best if the meshes (more precisely, their vertices) are exact copies of each other.
Otherwise, method used can only perform an approximated best match, which means you'll likely get better
results if you 'visually' make them match in 3D space (and use 'Object Transform') instead.
Titles says everything, just two notes:
* We have to actually transfer plain *normals*, not 'compressed' clnors,
so had to add pre/post process to transfer to make the conversions.
* Also added interpolation and advanced copy/mixing to CD_NORMAL, for same reasons.
Mesh stores its dvert in a specific pointer too, in addition of regular CD layer...
That whole vgroup handling is really breaking apart the 'universality' of CD system. :(
Also added some DAG and WM updates in operators...
Needed to replace weight transfer modifier in WeightPaint mode...
Note this is not exposed to users in UI, shall remain technical intern
parameter imho. Esp. since behavior when several sources is a bit 'random'
(merely uses each source in selection order...).
Also, this correct a bug, where 'lib' linked objects/meshes could not be used
as source...
Not much to add, modifier uses same code as operator basically, only key difference
is that modifier will never create data layers itself, you have to use dedicated operator
for that.
This add code needed to map a CD data layout from source mesh towards destination one,
and code needed to actually transfer data, using BKE's mesh remap generated data.
This allows to transfer most CD layers (vgroups, vcols, uvs...) as well as fake, boolean ones
(like smooth/sharp edges/faces, etc.). Some types are not yet transferable, mainly
shape keys, this is known TODO.
Data transfer can also use some advanced mixing in some cases (mostly, vgroups and vcols).
Notes:
* New transfer operators transfer data from active object towards selected ones.
* Modifier will be committed separately.
* Old weight transfer code (for vgroups) is kept for now, mostly because it is the only
usable one in weightpaint mode (it transfers from selected object to active one,
this is not sensible in Object mode, but needed in WeightPaint one). This will be addressed soon.
Again, heavily reviewed and enhanced by Campbell, thanks!
