Those new functions invert the winding of polygons, effectively inverting their normals.
A helper was also added to allow swapping two items in customdata layers.
Being able to invert normals outside of BMesh area is very important in several places,
like IO scripts or customnormals modifiers...
Reviewers: campbellbarton
Differential Revision: https://developer.blender.org/D1814
The final stage of the process (copying/interpolating new dst cddata from src cddata)
was simply broken in normal case, where we need to convert from source to destination
object space.
This patch is a bit verbose, but I cannot see how to avoid it really.
To think this code is in master since over 6 months and it only gets reported now... :/
Issue is rather well explained in T45471: our current customdata writing code easily generates several different blocks in blend file with same 'old' address. This is bad, because those addresses are used as 'uid' during reading process (it kind of work in Blender's own reading process, by mere luck mostly, but breaks the file specs).
Solution (suggested by Campbell, thanks) implemented by this patch is to avoid duplicating everything, and instead just overwrite what we needs to skip some cdlayers on write:
* the CustomData's `totlayer` number;
* the CustomData's `layers` array of CustomDataLayer (keeping its original address using the `writestruct_at_address` helper).
New design allows us to get completely rid of the no_free flag stuff in `write_customdata()`.
Note that this implies written data is **not** directly valid from Blend PoV, since its written typemap does not match written layers (this is not an issue because typemap is rebuilt on read anyway - and it's easy to fix this if really needed).
Also, the backward compatibility saving of mface data remains an issue here, see comment in code.
Reviewers: sergey, campbellbarton
Projects: #bf_blender
Maniphest Tasks: T45471
Differential Revision: https://developer.blender.org/D1425
The idea is pretty simple: instead of making temporary copy of all the
related custom data layers just pass the ownership from the DM to the
mesh.
This is really handy in cases when you've got DM which you need to
convert to Mesh datablock and wouldn't need that DM after conversion
anyway.
Foe example, render database conversion, exporters and even Modifier
Apply will benefit from this option.
Reviewers: campbellbarton
Differential Revision: https://developer.blender.org/D1127
`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.
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.
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!
This is only an indirect fix, in fact: this commit adds a public API to check
the maximum number of a given layer type (`CustomData_layertype_layers_max()`),
and uses it to forbid too much layer creation in `CustomData_merge()`.
This only affects UVs/VCol data though, but merge behavior in itself is not a bug
actually, how user managed to get thousands of different UV layer names remain
rather mysterious...
(which is also "[#36749] Joining objects with more than one uv map depends on list order")
Thanks Bastien Montagne and Brecht van Lommel for reviewing and some advice.
note: that this intentionally removes check to exit vpaint mode when a vertex color layer is removed,
since being in vertex-paint mode without a vertex color layer is supported.
also minor change to drawing camera limits while picking from previous commit.
