Changes from custom-manipulator branch.
- use property type definitions.
- add property free callback.
- move properties into the wmManipulator struct (over alloc).
- use array length from property types instead of arg passing.
This makes manipulator access closer to operators,
and allows Python access.
This adds RNA for manipulators, but not Python registration yet.
- Split draw style into 2x settings:
`draw_style` (enum) & `draw_options` (enum-flag)
- Rename wmManipulator.properties -> properties_edit,
Use wmManipulator.properties for ID-properties.
Note that this area of the API will need further work since
manipulators now have 2 kinds of properties & API's to access them.
This is needed so manipulators can tag themselves for removal
without causing problems from freeing data within a callback.
Also use properties within the dial manipulator and fix an error where
removing a wmManipulatorGroupType didn't remove its keymap.
While this is work-in-progress from custom-manipulators branch
its stable so adding into 2.8 so we don't get too much out of sync.
- ManipulatorGroupType's are moved out of the manipulator-map and are now
global (like operators, panels etc) and added into spaces as needed.
Without this all operators that might ever use a manipulator in the 3D
view would be polling the viewport.
- Add optional get/set callbacks for non-RNA properties
Needed so re-usable manipulators can control values that
don't correspond to a single properly or need conversion.
- Fix divide by zero bug in arrow manipulator (when moving zero pixels).
Sync with custom-manipulators branch
- Use identifiers for properties.
- Property array index access.
- Remove operator from manipulators
(wasn't used and will likely add in a different way).
- Move callbacks into type struct.
- Rename render_3d_intersection -> draw_select.
- Add header for function signatures (needed for types and api headers).
- Add WM_manipulatormaptype_find
This commit lands the core backend of the Custom Manipulators project onto the blender2.8 branch. It is a generic backend for managinig interactive on-screen controls that can be integrated into any 2D or 3D edito. It's also already integrated into the window-manager and editor code where needed.
NOTE: The changes here should not be visible for users at all. It's really just a back-end patch. Neither does this include any RNA or Python integration.
Of course, there's still lots of work ahead for custom manipulators, but this is a big milestone. WIP code that actually uses this backend can be found in the 'custom-manipulators' branch (previously called 'wiggly-widgets').
The work here isn't completely my own, all the initial work was done by @Antony Riakiotakis (psy-fi) and - although it has changed a lot since them - it's still the same in essence. He definitely deserves a big credit! Some changes in this patch were also done by @Campbell Barton (campbellbarton). Thank you guys!
Merge accepted by @brecht and @merwin.
Patch: https://developer.blender.org/D2232
Code documentation: https://wiki.blender.org/index.php/Dev:2.8/Source/Custom_Manipulator
Main task: https://developer.blender.org/T47343
More info: https://code.blender.org/2015/09/the-custom-manipulator-project-widget-project/
