Custom Manipulators Core Backend

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/

1 files changed, 14 insertions, 0 deletions

diff --git a/source/blender/blenkernel/intern/screen.c b/source/blender/blenkernel/intern/screen.c
index 857bd5447c8..14820565478 100644
--- a/source/blender/blenkernel/intern/screen.c
+++ b/source/blender/blenkernel/intern/screen.c
@@ -180,6 +180,7 @@ ARegion *BKE_area_region_copy(SpaceType *st, ARegion *ar)
 	BLI_listbase_clear(&newar->panels_category_active);
 	BLI_listbase_clear(&newar->ui_lists);
 	newar->swinid = 0;
+	newar->manipulator_map = NULL;
 	newar->regiontimer = NULL;
 	
 	/* use optional regiondata callback */
@@ -288,6 +289,17 @@ void BKE_spacedata_id_unref(struct ScrArea *sa, struct SpaceLink *sl, struct ID
 	}
 }
 
+
+/**
+ * Avoid bad-level calls to #WM_manipulatormap_delete.
+ */
+static void (*region_free_manipulatormap_callback)(struct wmManipulatorMap *) = NULL;
+
+void BKE_region_callback_free_manipulatormap_set(void (*callback)(struct wmManipulatorMap *))
+{
+	region_free_manipulatormap_callback = callback;
+}
+
 /* not region itself */
 void BKE_area_region_free(SpaceType *st, ARegion *ar)
 {
@@ -337,6 +349,8 @@ void BKE_area_region_free(SpaceType *st, ARegion *ar)
 			MEM_freeN(uilst->properties);
 		}
 	}
+
+	region_free_manipulatormap_callback(ar->manipulator_map);
 	BLI_freelistN(&ar->ui_lists);
 	BLI_freelistN(&ar->ui_previews);
 	BLI_freelistN(&ar->panels_category);