Blender Git Loki

Merge remote-tracking branch 'origin/master' into asset-browser-snap-dragging

Merge remote-tracking branch 'origin/master' into asset-browser-snap-dragging

Merge remote-tracking branch 'origin/master' into asset-browser-snap-dragging

Basic snapping support for dropping objects

Uses the same snapping logic as the placement plane from the Add Object
tool, which means it matches the plane that we already draw as a
preview.

This is quite primitive at this point - you can't change options for the
snapping like the up-axis or the snapping target - but it already feels
quite great.
Another limitation is that it uses the origin of the dropped object to
place it, the bounding box should give better results in practice. This
is something we can add.

Merge branch 'master' into asset-browser-snap-dragging

Initial prototype for snapping plane feedback while dragging assets

Shows the same grid overlay as the Add Object tool when dragging an
asset into a 3D view. Uses the gizmo-system for that.
How visibility of gizmo-groups is managed is rather tricky, for now I
hacked things a bit to work. I have ideas to make this nicer.

Besides that, this is generally a design that I think can work in
master: Just like tools, drop-boxes can set a gizmo-group to use while
they are active. If the gizmo-group supports usage while dragging, it is
drawn.