Previously, hitting Shift-LMB will first invoke selection operator, which
then later on is transformed to mouse tweak used for reroute operator.
This was causing problems extending selection with Shift-LMB when clicking
fast or from a tablet.
When one creates a new local static override from another linked
data-block already overriding a third one etc., walk the whole
inheritance chain up to the original ancestor to try to find an
overriding template, instead of only checking the immediate reference...
Avoid creating new Python instances
every time a scene, object, mesh .. etc are accessed.
Also resolves crashes T28724, T53530
although it's only valid for ID types, not modifiers vertices etc.
Back-ported from blender2.8 branch.
WorkSpaceLayout->screen will be made public soon, but meanwhile this makes it
clear why we are not passing layout->screen to CALLBACK_INVOKE in this case.
We can not store pointer to an object ion temporary variable here, since then
pointer will not be updated in the base itself.
This fixes missing modifiers on objects coming from dupli-group.
Bug introduced on rB9f5bf197a0c3.
The offset for selection of vertices (`bm_vertoffs`) starts where the offset o edges ends (`bm_wireoffs`).
However, the `bm_wireoffs` depends on the offset of face selection (`bm_solidoffs`).
Before the commit that introduced the bug, the drawn of edges (in backbuff) was always computed along with the `bm_wireoffs`:
```
bm_wireoffs = bm_solidoffs + em->bm->totedge;
```
Now that the edges are not always drawn in backbuff, `bm_wireoffs` has to start from `bm_solidoffs`.
It is still based on generic collection evaluation, but the idea is to avoid
having view_layer pointer passed from group to it's evaluation function.
This is essential for copy-on-write, where we need to pass view_layer pointer
from a copied datablock, but that copy is not yet available at construction
time. Also, this is NOT the case where we want to expand datablock at a
construction time, just to keep our life easier.
View Layer was not duplicated between destination and source.
This would lead to a crash if you duplicated the group and assigned
the new group to any object.
Our own implementation was behaving different comparing to OSL and GPU,
namely on the border pixels OSL and CUDA was doing interpolation with
black, but we were clamping coordinate.
This partially fixes issue reported in T53452.
Similar change should also be done for 3D interpolation perhaps, but this
is to be investigated separately.
