Blender Git Loki

Applied my work from temp-sybren-poselib branch.

Still a bit rough. For example, the viewport used for OpenGL rendering is
more or less randomly chosen from the current screen.

Removed pep8 compliance note.

Added a little note about some hackyness.

Merge branch 'master' into temp-sybren-poselib

Merge branch 'master' into multi_previews_id

Add preview to Action datablock.

Hopefully did not forget anything.

Some UI access to multi-frames icons...

Not so happy to have to change whole UI API like that, but... can't
really see another solution, since layout API does not return any
handler to button(s) it creates. :/

Add first basic RNA API for multi-frames previews.

Not much to say here, still more to add, but this should be enough for a
first basic usage.

Multi-previews: basics (not yet usable from end-user code).

This commits adds data and basic API needed to handle multi-previews in
a single PreviewImage struct.

Data model is designed to be fully compatible (backward and forward)
with previous one, while keeping a 'flat array' design to store
previews. It also adds an extra integer per frame, that may be used to
store various meta-data.

This commit also updates write/read code, and adds basic BKE API to handle
multiple frames.

TODO: UI code (only very minimal stuff done so far, probably want to add
some template options too...). Access between icon ID and preview frames
is not yet fully designed, but think will rather go with an extra
integer rather that generating an icon ID/icon struct for every frame.

Merge branch 'master' into temp-sybren-poselib

Merge branch 'master' into temp-sybren-poselib

Explicitly switch to camera from either pose or scene marker.

Fix

Merge branch 'master' into temp-sybren-poselib

More poselib stuff

Merge branch 'master' into temp-sybren-poselib

More UI stuff, still very rough and depends on pose lib preview property.

Poselib UI tweaks

Allow only cameras to be assigned to the TimelineMarker.camera prop

Merge branch 'master' into temp-sybren-poselib