Blender Git Loki

Fix clipboard copying collections when copying objects from 3DView.

This was inherited from 2.7x behavior with groups, but in 2.8
collections are also used as 2.7x layers, which turns to be a problem
when pasting back clipboard content, since it would instantiate
collections instead of objects, quickly leading to tens of new
collections in the viewlayer...

Instead, we only copy selected objects from the 3DView now. On paste
time, those will be added to the active collection.

Last part of fixes related to T61670.

Fix T62802: Layer order inverted in Outliner

Cleanup: move functions into doxy sections

Also use const args for queries.

Cleanup: use doxy sections for interface_handlers

Cleanup: move scroll step into own function

UI: popovers scroll now changes offset directly

Mouse wheel on menus changes the selected item item which doesn't work
well for popovers since buttons aren't always stacked vertically.

Resolves T62777

Cleanup: split menu scrolling function

The same function scrolled to a location and button (depending on args).

Fix T62782: Edge slide crashes with mirror enabled

Viewport: Draw loose edges in edit mesh mode if there is a modifier stack

Fix DEG warning from T52873: Proximity WeightVG modifier can use empty as target too.

Only create DEG_OB_COMP_GEOMETRY relation to target object when it has
some, and we use it.

Fix T58748 Mirror modifier: edges/verts invisible unless face is present

It was due to the mapped mesh not being used if no face was present in the
cage mesh.

Fix T60815: drag & drop crash when search menu is opened immediately after.

Patch by matc, some further refactoring by me.

Differential Revision: https://developer.blender.org/D4250

Fix T62788: drop image into node editor puts node at wrong location.

It should be under the mouse cursor but was wrong for high DPI. Also put the
cursor in the header now so it's easy to reposition.

Merge branch 'blender2.7'

Fix assert after recent changes.

Mark as localized immediately, so that functions that edit the node tree can
verify they are being used under the correct conditions.

Fix cycles.merge_images not merging correctly for some channel layouts.

Merge branch 'blender2.7'

Cycles: make cycles.merge_images work with incomplete layers and passes.

If layers and passes are not exactly the same in all files, we make a best
effort to merge them instead of failing.

Fix T62758: hair curves with UV mapped textures renders wrong.

Differential Revision: https://developer.blender.org/D4562

Fix T61326 "In Front" option not working on edit curves

Create a new pass for them and draw them separately.

Beware of the double multisample resolve when multi-editing a mix of curves
with and without the "in front" option enabled.