WM: pass on wmDrag to drop operators, so they can get the data directly.

Currently drop operators work mostly by specifying the name of the datablock.
However there can be datablocks with the same name in different libraries, so
this gives wrong results in some cases.

Currently only outliner drop operators have been updated to use this mechanism.

1 files changed, 242 insertions, 400 deletions

diff --git a/source/blender/editors/space_outliner/outliner_dragdrop.c b/source/blender/editors/space_outliner/outliner_dragdrop.c
index c53a431a017..f9a4fda0c45 100644
--- a/source/blender/editors/space_outliner/outliner_dragdrop.c
+++ b/source/blender/editors/space_outliner/outliner_dragdrop.c
@@ -39,6 +39,7 @@
 #include "DNA_space_types.h"
 
 #include "BLI_listbase.h"
+#include "BLI_string.h"
 
 #include "BLT_translation.h"
 
@@ -105,64 +106,77 @@ static TreeElement *outliner_dropzone_find(const SpaceOops *soops, const float f
 	return NULL;
 }
 
-/* ******************** Parent Drop Operator *********************** */
-
-static bool parent_drop_poll(bContext *C, wmDrag *drag, const wmEvent *event, const char **UNUSED(tooltip))
+static TreeElement *outliner_drop_find(bContext *C, const wmEvent *event)
 {
 	ARegion *ar = CTX_wm_region(C);
 	SpaceOops *soops = CTX_wm_space_outliner(C);
 	float fmval[2];
 	UI_view2d_region_to_view(&ar->v2d, event->mval[0], event->mval[1], &fmval[0], &fmval[1]);
 
-	if (drag->type == WM_DRAG_ID) {
-		ID *id = drag->poin;
-		if (GS(id->name) == ID_OB) {
-			/* Ensure item under cursor is valid drop target */
-			TreeElement *te = outliner_dropzone_find(soops, fmval, true);
-			TreeStoreElem *tselem = te ? TREESTORE(te) : NULL;
+	return outliner_dropzone_find(soops, fmval, true);
+}
 
-			if (!te) {
-				/* pass */
-			}
-			else if (te->idcode == ID_OB && tselem->type == 0) {
-				Scene *scene;
-				ID *te_id = tselem->id;
-
-				/* check if dropping self or parent */
-				if (te_id == id || (Object *)te_id == ((Object *)id)->parent)
-					return 0;
-
-				/* check that parent/child are both in the same scene */
-				scene = (Scene *)outliner_search_back(soops, te, ID_SCE);
-
-				/* currently outliner organized in a way that if there's no parent scene
-				 * element for object it means that all displayed objects belong to
-				 * active scene and parenting them is allowed (sergey)
-				 */
-				if (!scene) {
-					return 1;
-				}
-				else {
-					for (ViewLayer *view_layer = scene->view_layers.first;
-					     view_layer;
-					     view_layer = view_layer->next)
-					{
-						if (BKE_view_layer_base_find(view_layer, (Object *)id)) {
-							return 1;
-						}
-					}
-				}
-			}
-		}
+static ID *outliner_ID_drop_find(bContext *C, const wmEvent *event, short idcode)
+{
+	TreeElement *te = outliner_drop_find(C, event);
+	TreeStoreElem *tselem = (te) ? TREESTORE(te) : NULL;
+
+	if (te && te->idcode == idcode && tselem->type == 0) {
+		return tselem->id;
+	}
+	else {
+		return NULL;
 	}
-	return 0;
 }
 
-static void parent_drop_copy(wmDrag *drag, wmDropBox *drop)
+/* ******************** Parent Drop Operator *********************** */
+
+static bool parent_drop_poll(bContext *C, wmDrag *drag, const wmEvent *event, const char **UNUSED(tooltip))
 {
-	ID *id = drag->poin;
+	SpaceOops *soops = CTX_wm_space_outliner(C);
+	Object *ob = (Object *)WM_drag_ID(drag, ID_OB);
+	if (!ob) {
+		return false;
+	}
+
+	/* Ensure item under cursor is valid drop target */
+	TreeElement *te = outliner_drop_find(C, event);
+	TreeStoreElem *tselem = te ? TREESTORE(te) : NULL;
+
+	if (!te) {
+		/* pass */
+	}
+	else if (te->idcode == ID_OB && tselem->type == 0) {
+		Scene *scene;
+		ID *te_id = tselem->id;
+
+		/* check if dropping self or parent */
+		if (te_id == &ob->id || (Object *)te_id == ob->parent)
+			return false;
+
+		/* check that parent/child are both in the same scene */
+		scene = (Scene *)outliner_search_back(soops, te, ID_SCE);
+
+		/* currently outliner organized in a way that if there's no parent scene
+		 * element for object it means that all displayed objects belong to
+		 * active scene and parenting them is allowed (sergey)
+		 */
+		if (!scene) {
+			return true;
+		}
+		else {
+			for (ViewLayer *view_layer = scene->view_layers.first;
+				 view_layer;
+				 view_layer = view_layer->next)
+			{
+				if (BKE_view_layer_base_find(view_layer, ob)) {
+					return true;
+				}
+			}
+		}
+	}
 
-	RNA_string_set(drop->ptr, "child", id->name + 2);
+	return false;
 }
 
 static int parent_drop_exec(bContext *C, wmOperator *op)
@@ -195,131 +209,121 @@ static int parent_drop_exec(bContext *C, wmOperator *op)
 
 static int parent_drop_invoke(bContext *C, wmOperator *op, const wmEvent *event)
 {
-	Object *par = NULL;
-	Object *ob = NULL;
-	SpaceOops *soops = CTX_wm_space_outliner(C);
-	ARegion *ar = CTX_wm_region(C);
 	Main *bmain = CTX_data_main(C);
-	Scene *scene = NULL;
-	TreeElement *te = NULL;
+	SpaceOops *soops = CTX_wm_space_outliner(C);
+	TreeElement *te = outliner_drop_find(C, event);
+	TreeStoreElem *tselem = te ? TREESTORE(te) : NULL;
+
+	if (!(te && te->idcode == ID_OB && tselem->type == 0)) {
+		return OPERATOR_CANCELLED;
+	}
+
+	Object *par = (Object *)tselem->id;
+	Object *ob = (Object *)WM_drag_ID_from_event(event, ID_OB);
+
+	if (ELEM(NULL, ob, par)) {
+		return OPERATOR_CANCELLED;
+	}
+	if (ob == par) {
+		return OPERATOR_CANCELLED;
+	}
+	if (ID_IS_LINKED(ob)) {
+		BKE_report(op->reports, RPT_INFO, "Can't edit library linked object");
+		return OPERATOR_CANCELLED;
+	}
+
 	char childname[MAX_ID_NAME];
 	char parname[MAX_ID_NAME];
-	int partype = 0;
-	float fmval[2];
+	STRNCPY(childname, ob->id.name);
+	STRNCPY(parname, par->id.name);
+	RNA_string_set(op->ptr, "child", childname);
+	RNA_string_set(op->ptr, "parent", parname);
 
-	UI_view2d_region_to_view(&ar->v2d, event->mval[0], event->mval[1], &fmval[0], &fmval[1]);
+	Scene *scene = (Scene *)outliner_search_back(soops, te, ID_SCE);
 
-	/* Find object hovered over */
-	te = outliner_dropzone_find(soops, fmval, true);
+	if (scene == NULL) {
+		/* currently outlier organized in a way, that if there's no parent scene
+		 * element for object it means that all displayed objects belong to
+		 * active scene and parenting them is allowed (sergey)
+		 */
 
-	if (te) {
-		RNA_string_set(op->ptr, "parent", te->name);
-		/* Identify parent and child */
-		RNA_string_get(op->ptr, "child", childname);
-		ob = (Object *)BKE_libblock_find_name(bmain, ID_OB, childname);
-		RNA_string_get(op->ptr, "parent", parname);
-		par = (Object *)BKE_libblock_find_name(bmain, ID_OB, parname);
-
-		if (ELEM(NULL, ob, par)) {
-			if (par == NULL) printf("par==NULL\n");
-			return OPERATOR_CANCELLED;
-		}
-		if (ob == par) {
-			return OPERATOR_CANCELLED;
-		}
-		if (ID_IS_LINKED(ob)) {
-			BKE_report(op->reports, RPT_INFO, "Can't edit library linked object");
-			return OPERATOR_CANCELLED;
+		scene = CTX_data_scene(C);
+	}
+
+	if ((par->type != OB_ARMATURE) && (par->type != OB_CURVE) && (par->type != OB_LATTICE)) {
+		int partype = 0;
+		if (ED_object_parent_set(op->reports, C, scene, ob, par, partype, false, false, NULL)) {
+			DEG_relations_tag_update(bmain);
+			WM_event_add_notifier(C, NC_OBJECT | ND_TRANSFORM, NULL);
+			WM_event_add_notifier(C, NC_OBJECT | ND_PARENT, NULL);
 		}
+	}
+	else {
+		/* Menu creation */
+		wmOperatorType *ot = WM_operatortype_find("OUTLINER_OT_parent_drop", false);
+		uiPopupMenu *pup = UI_popup_menu_begin(C, IFACE_("Set Parent To"), ICON_NONE);
+		uiLayout *layout = UI_popup_menu_layout(pup);
+		PointerRNA ptr;
+
+		/* Cannot use uiItemEnumO()... have multiple properties to set. */
+		uiItemFullO_ptr(layout, ot, IFACE_("Object"), 0, NULL, WM_OP_EXEC_DEFAULT, 0, &ptr);
+		RNA_string_set(&ptr, "parent", parname);
+		RNA_string_set(&ptr, "child", childname);
+		RNA_enum_set(&ptr, "type", PAR_OBJECT);
+
+		/* par becomes parent, make the associated menus */
+		if (par->type == OB_ARMATURE) {
+			uiItemFullO_ptr(layout, ot, IFACE_("Armature Deform"), 0, NULL, WM_OP_EXEC_DEFAULT, 0, &ptr);
+			RNA_string_set(&ptr, "parent", parname);
+			RNA_string_set(&ptr, "child", childname);
+			RNA_enum_set(&ptr, "type", PAR_ARMATURE);
 
-		scene = (Scene *)outliner_search_back(soops, te, ID_SCE);
+			uiItemFullO_ptr(layout, ot, IFACE_("   With Empty Groups"), 0, NULL, WM_OP_EXEC_DEFAULT, 0, &ptr);
+			RNA_string_set(&ptr, "parent", parname);
+			RNA_string_set(&ptr, "child", childname);
+			RNA_enum_set(&ptr, "type", PAR_ARMATURE_NAME);
 
-		if (scene == NULL) {
-			/* currently outlier organized in a way, that if there's no parent scene
-			 * element for object it means that all displayed objects belong to
-			 * active scene and parenting them is allowed (sergey)
-			 */
+			uiItemFullO_ptr(layout, ot, IFACE_("   With Envelope Weights"), 0, NULL, WM_OP_EXEC_DEFAULT, 0, &ptr);
+			RNA_string_set(&ptr, "parent", parname);
+			RNA_string_set(&ptr, "child", childname);
+			RNA_enum_set(&ptr, "type", PAR_ARMATURE_ENVELOPE);
 
-			scene = CTX_data_scene(C);
-		}
+			uiItemFullO_ptr(layout, ot, IFACE_("   With Automatic Weights"), 0, NULL, WM_OP_EXEC_DEFAULT, 0, &ptr);
+			RNA_string_set(&ptr, "parent", parname);
+			RNA_string_set(&ptr, "child", childname);
+			RNA_enum_set(&ptr, "type", PAR_ARMATURE_AUTO);
 
-		if ((par->type != OB_ARMATURE) && (par->type != OB_CURVE) && (par->type != OB_LATTICE)) {
-			if (ED_object_parent_set(op->reports, C, scene, ob, par, partype, false, false, NULL)) {
-				DEG_relations_tag_update(bmain);
-				WM_event_add_notifier(C, NC_OBJECT | ND_TRANSFORM, NULL);
-				WM_event_add_notifier(C, NC_OBJECT | ND_PARENT, NULL);
-			}
+			uiItemFullO_ptr(layout, ot, IFACE_("Bone"), 0, NULL, WM_OP_EXEC_DEFAULT, 0, &ptr);
+			RNA_string_set(&ptr, "parent", parname);
+			RNA_string_set(&ptr, "child", childname);
+			RNA_enum_set(&ptr, "type", PAR_BONE);
 		}
-		else {
-			/* Menu creation */
-			wmOperatorType *ot = WM_operatortype_find("OUTLINER_OT_parent_drop", false);
-			uiPopupMenu *pup = UI_popup_menu_begin(C, IFACE_("Set Parent To"), ICON_NONE);
-			uiLayout *layout = UI_popup_menu_layout(pup);
-			PointerRNA ptr;
-
-			/* Cannot use uiItemEnumO()... have multiple properties to set. */
-			uiItemFullO_ptr(layout, ot, IFACE_("Object"), 0, NULL, WM_OP_EXEC_DEFAULT, 0, &ptr);
+		else if (par->type == OB_CURVE) {
+			uiItemFullO_ptr(layout, ot, IFACE_("Curve Deform"), 0, NULL, WM_OP_EXEC_DEFAULT, 0, &ptr);
 			RNA_string_set(&ptr, "parent", parname);
 			RNA_string_set(&ptr, "child", childname);
-			RNA_enum_set(&ptr, "type", PAR_OBJECT);
-
-			/* par becomes parent, make the associated menus */
-			if (par->type == OB_ARMATURE) {
-				uiItemFullO_ptr(layout, ot, IFACE_("Armature Deform"), 0, NULL, WM_OP_EXEC_DEFAULT, 0, &ptr);
-				RNA_string_set(&ptr, "parent", parname);
-				RNA_string_set(&ptr, "child", childname);
-				RNA_enum_set(&ptr, "type", PAR_ARMATURE);
-
-				uiItemFullO_ptr(layout, ot, IFACE_("   With Empty Groups"), 0, NULL, WM_OP_EXEC_DEFAULT, 0, &ptr);
-				RNA_string_set(&ptr, "parent", parname);
-				RNA_string_set(&ptr, "child", childname);
-				RNA_enum_set(&ptr, "type", PAR_ARMATURE_NAME);
-
-				uiItemFullO_ptr(layout, ot, IFACE_("   With Envelope Weights"), 0, NULL, WM_OP_EXEC_DEFAULT, 0, &ptr);
-				RNA_string_set(&ptr, "parent", parname);
-				RNA_string_set(&ptr, "child", childname);
-				RNA_enum_set(&ptr, "type", PAR_ARMATURE_ENVELOPE);
-
-				uiItemFullO_ptr(layout, ot, IFACE_("   With Automatic Weights"), 0, NULL, WM_OP_EXEC_DEFAULT, 0, &ptr);
-				RNA_string_set(&ptr, "parent", parname);
-				RNA_string_set(&ptr, "child", childname);
-				RNA_enum_set(&ptr, "type", PAR_ARMATURE_AUTO);
-
-				uiItemFullO_ptr(layout, ot, IFACE_("Bone"), 0, NULL, WM_OP_EXEC_DEFAULT, 0, &ptr);
-				RNA_string_set(&ptr, "parent", parname);
-				RNA_string_set(&ptr, "child", childname);
-				RNA_enum_set(&ptr, "type", PAR_BONE);
-			}
-			else if (par->type == OB_CURVE) {
-				uiItemFullO_ptr(layout, ot, IFACE_("Curve Deform"), 0, NULL, WM_OP_EXEC_DEFAULT, 0, &ptr);
-				RNA_string_set(&ptr, "parent", parname);
-				RNA_string_set(&ptr, "child", childname);
-				RNA_enum_set(&ptr, "type", PAR_CURVE);
-
-				uiItemFullO_ptr(layout, ot, IFACE_("Follow Path"), 0, NULL, WM_OP_EXEC_DEFAULT, 0, &ptr);
-				RNA_string_set(&ptr, "parent", parname);
-				RNA_string_set(&ptr, "child", childname);
-				RNA_enum_set(&ptr, "type", PAR_FOLLOW);
-
-				uiItemFullO_ptr(layout, ot, IFACE_("Path Constraint"), 0, NULL, WM_OP_EXEC_DEFAULT, 0, &ptr);
-				RNA_string_set(&ptr, "parent", parname);
-				RNA_string_set(&ptr, "child", childname);
-				RNA_enum_set(&ptr, "type", PAR_PATH_CONST);
-			}
-			else if (par->type == OB_LATTICE) {
-				uiItemFullO_ptr(layout, ot, IFACE_("Lattice Deform"), 0, NULL, WM_OP_EXEC_DEFAULT, 0, &ptr);
-				RNA_string_set(&ptr, "parent", parname);
-				RNA_string_set(&ptr, "child", childname);
-				RNA_enum_set(&ptr, "type", PAR_LATTICE);
-			}
+			RNA_enum_set(&ptr, "type", PAR_CURVE);
 
-			UI_popup_menu_end(C, pup);
+			uiItemFullO_ptr(layout, ot, IFACE_("Follow Path"), 0, NULL, WM_OP_EXEC_DEFAULT, 0, &ptr);
+			RNA_string_set(&ptr, "parent", parname);
+			RNA_string_set(&ptr, "child", childname);
+			RNA_enum_set(&ptr, "type", PAR_FOLLOW);
 
-			return OPERATOR_INTERFACE;
+			uiItemFullO_ptr(layout, ot, IFACE_("Path Constraint"), 0, NULL, WM_OP_EXEC_DEFAULT, 0, &ptr);
+			RNA_string_set(&ptr, "parent", parname);
+			RNA_string_set(&ptr, "child", childname);
+			RNA_enum_set(&ptr, "type", PAR_PATH_CONST);
 		}
-	}
-	else {
-		return OPERATOR_CANCELLED;
+		else if (par->type == OB_LATTICE) {
+			uiItemFullO_ptr(layout, ot, IFACE_("Lattice Deform"), 0, NULL, WM_OP_EXEC_DEFAULT, 0, &ptr);
+			RNA_string_set(&ptr, "parent", parname);
+			RNA_string_set(&ptr, "child", childname);
+			RNA_enum_set(&ptr, "type", PAR_LATTICE);
+		}
+
+		UI_popup_menu_end(C, pup);
+
+		return OPERATOR_INTERFACE;
 	}
 
 	return OPERATOR_FINISHED;
@@ -369,64 +373,42 @@ static bool parenting_poll(bContext *C)
 
 static bool parent_clear_poll(bContext *C, wmDrag *drag, const wmEvent *event, const char **UNUSED(tooltip))
 {
-	ARegion *ar = CTX_wm_region(C);
 	SpaceOops *soops = CTX_wm_space_outliner(C);
-	TreeElement *te = NULL;
-	float fmval[2];
-
-	UI_view2d_region_to_view(&ar->v2d, event->mval[0], event->mval[1], &fmval[0], &fmval[1]);
 
 	if (!ELEM(soops->outlinevis, SO_VIEW_LAYER)) {
 		return false;
 	}
 
-	if (drag->type == WM_DRAG_ID) {
-		ID *id = drag->poin;
-		if (GS(id->name) == ID_OB) {
-			if (((Object *)id)->parent) {
-				if ((te = outliner_dropzone_find(soops, fmval, true))) {
-					TreeStoreElem *tselem = TREESTORE(te);
-
-					switch (te->idcode) {
-						case ID_SCE:
-							return (ELEM(tselem->type, TSE_R_LAYER_BASE, TSE_R_LAYER));
-						case ID_OB:
-							return (ELEM(tselem->type, TSE_MODIFIER_BASE, TSE_CONSTRAINT_BASE));
-						/* Other codes to ignore? */
-					}
-				}
-				return (te == NULL);
-			}
-		}
+	Object *ob = (Object *)WM_drag_ID(drag, ID_OB);
+	if (!(ob && ob->parent)) {
+		return false;
 	}
-	return 0;
-}
-
-static void parent_clear_copy(wmDrag *drag, wmDropBox *drop)
-{
-	ID *id = drag->poin;
-	RNA_string_set(drop->ptr, "dragged_obj", id->name + 2);
 
-	/* Set to simple parent clear type. Avoid menus for drag and drop if possible.
-	 * If desired, user can toggle the different "Clear Parent" types in the operator
-	 * menu on tool shelf. */
-	RNA_enum_set(drop->ptr, "type", 0);
+	TreeElement *te = outliner_drop_find(C, event);
+	if (te) {
+		TreeStoreElem *tselem = TREESTORE(te);
+
+		switch (te->idcode) {
+			case ID_SCE:
+				return (ELEM(tselem->type, TSE_R_LAYER_BASE, TSE_R_LAYER));
+			case ID_OB:
+				return (ELEM(tselem->type, TSE_MODIFIER_BASE, TSE_CONSTRAINT_BASE));
+			/* Other codes to ignore? */
+		}
+	}
+	return (te == NULL);
 }
 
-static int parent_clear_invoke(bContext *C, wmOperator *op, const wmEvent *UNUSED(event))
+static int parent_clear_invoke(bContext *C, wmOperator *UNUSED(op), const wmEvent *event)
 {
 	Main *bmain = CTX_data_main(C);
-	Object *ob = NULL;
-	SpaceOops *soops = CTX_wm_space_outliner(C);
-	char obname[MAX_ID_NAME];
+	Object *ob = (Object *)WM_drag_ID_from_event(event, ID_OB);
 
-	RNA_string_get(op->ptr, "dragged_obj", obname);
-	ob = (Object *)BKE_libblock_find_name(bmain, ID_OB, obname);
-
-	/* search forwards to find the object */
-	outliner_find_id(soops, &soops->tree, (ID *)ob);
+	if (ob == NULL) {
+		return OPERATOR_CANCELLED;
+	}
 
-	ED_object_parent_clear(ob, RNA_enum_get(op->ptr, "type"));
+	ED_object_parent_clear(ob, 0);
 
 	DEG_relations_tag_update(bmain);
 	WM_event_add_notifier(C, NC_OBJECT | ND_TRANSFORM, NULL);
@@ -448,97 +430,55 @@ void OUTLINER_OT_parent_clear(wmOperatorType *ot)
 
 	/* flags */
 	ot->flag = OPTYPE_REGISTER | OPTYPE_UNDO | OPTYPE_INTERNAL;
-
-	/* properties */
-	RNA_def_string(ot->srna, "dragged_obj", "Object", MAX_ID_NAME, "Child", "Child Object");
-	RNA_def_enum(ot->srna, "type", prop_clear_parent_types, 0, "Type", "");
 }
 
 /* ******************** Scene Drop Operator *********************** */
 
 static bool scene_drop_poll(bContext *C, wmDrag *drag, const wmEvent *event, const char **UNUSED(tooltip))
 {
-	ARegion *ar = CTX_wm_region(C);
-	SpaceOops *soops = CTX_wm_space_outliner(C);
-	float fmval[2];
-	UI_view2d_region_to_view(&ar->v2d, event->mval[0], event->mval[1], &fmval[0], &fmval[1]);
-
-	if (drag->type == WM_DRAG_ID) {
-		ID *id = drag->poin;
-		if (GS(id->name) == ID_OB) {
-			/* Ensure item under cursor is valid drop target */
-			TreeElement *te = outliner_dropzone_find(soops, fmval, false);
-			return (te && te->idcode == ID_SCE && TREESTORE(te)->type == 0);
-		}
-	}
-	return 0;
-}
-
-static void scene_drop_copy(wmDrag *drag, wmDropBox *drop)
-{
-	ID *id = drag->poin;
-
-	RNA_string_set(drop->ptr, "object", id->name + 2);
+	/* Ensure item under cursor is valid drop target */
+	Object *ob = (Object *)WM_drag_ID(drag, ID_OB);
+	return (ob && (outliner_ID_drop_find(C, event, ID_SCE) != NULL));
 }
 
-static int scene_drop_invoke(bContext *C, wmOperator *op, const wmEvent *event)
+static int scene_drop_invoke(bContext *C, wmOperator *UNUSED(op), const wmEvent *event)
 {
-	Scene *scene = NULL;
-	Object *ob = NULL;
-	SpaceOops *soops = CTX_wm_space_outliner(C);
-	ARegion *ar = CTX_wm_region(C);
 	Main *bmain = CTX_data_main(C);
-	TreeElement *te = NULL;
-	char obname[MAX_ID_NAME];
-	float fmval[2];
-
-	UI_view2d_region_to_view(&ar->v2d, event->mval[0], event->mval[1], &fmval[0], &fmval[1]);
-
-	/* Find object hovered over */
-	te = outliner_dropzone_find(soops, fmval, false);
+	Scene *scene = (Scene *)outliner_ID_drop_find(C, event, ID_SCE);
+	Object *ob = (Object *)WM_drag_ID_from_event(event, ID_OB);
 
-	if (te) {
-		RNA_string_set(op->ptr, "scene", te->name);
-		scene = (Scene *)BKE_libblock_find_name(bmain, ID_SCE, te->name);
-
-		RNA_string_get(op->ptr, "object", obname);
-		ob = (Object *)BKE_libblock_find_name(bmain, ID_OB, obname);
-
-		if (ELEM(NULL, ob, scene) || ID_IS_LINKED(scene)) {
-			return OPERATOR_CANCELLED;
-		}
+	if (ELEM(NULL, ob, scene) || ID_IS_LINKED(scene)) {
+		return OPERATOR_CANCELLED;
+	}
 
-		if (BKE_scene_has_object(scene, ob)) {
-			return OPERATOR_CANCELLED;
-		}
+	if (BKE_scene_has_object(scene, ob)) {
+		return OPERATOR_CANCELLED;
+	}
 
-		Collection *collection;
-		if (scene != CTX_data_scene(C)) {
-			/* when linking to an inactive scene link to the master collection */
-			collection = BKE_collection_master(scene);
-		}
-		else {
-			collection = CTX_data_collection(C);
-		}
+	Collection *collection;
+	if (scene != CTX_data_scene(C)) {
+		/* when linking to an inactive scene link to the master collection */
+		collection = BKE_collection_master(scene);
+	}
+	else {
+		collection = CTX_data_collection(C);
+	}
 
-		BKE_collection_object_add(bmain, collection, ob);
+	BKE_collection_object_add(bmain, collection, ob);
 
-		for (ViewLayer *view_layer = scene->view_layers.first; view_layer; view_layer = view_layer->next) {
-			Base *base = BKE_view_layer_base_find(view_layer, ob);
-			if (base) {
-				ED_object_base_select(base, BA_SELECT);
-			}
+	for (ViewLayer *view_layer = scene->view_layers.first; view_layer; view_layer = view_layer->next) {
+		Base *base = BKE_view_layer_base_find(view_layer, ob);
+		if (base) {
+			ED_object_base_select(base, BA_SELECT);
 		}
+	}
 
-		DEG_relations_tag_update(bmain);
-
-		DEG_id_tag_update(&scene->id, DEG_TAG_SELECT_UPDATE);
-		WM_main_add_notifier(NC_SCENE | ND_OB_SELECT, scene);
+	DEG_relations_tag_update(bmain);
 
-		return OPERATOR_FINISHED;
-	}
+	DEG_id_tag_update(&scene->id, DEG_TAG_SELECT_UPDATE);
+	WM_main_add_notifier(NC_SCENE | ND_OB_SELECT, scene);
 
-	return OPERATOR_CANCELLED;
+	return OPERATOR_FINISHED;
 }
 
 void OUTLINER_OT_scene_drop(wmOperatorType *ot)
@@ -555,75 +495,33 @@ void OUTLINER_OT_scene_drop(wmOperatorType *ot)
 
 	/* flags */
 	ot->flag = OPTYPE_REGISTER | OPTYPE_UNDO | OPTYPE_INTERNAL;
-
-	/* properties */
-	RNA_def_string(ot->srna, "object", "Object", MAX_ID_NAME, "Object", "Target Object");
-	RNA_def_string(ot->srna, "scene", "Scene", MAX_ID_NAME, "Scene", "Target Scene");
 }
 
 /* ******************** Material Drop Operator *********************** */
 
 static bool material_drop_poll(bContext *C, wmDrag *drag, const wmEvent *event, const char **UNUSED(tooltip))
 {
-	ARegion *ar = CTX_wm_region(C);
-	SpaceOops *soops = CTX_wm_space_outliner(C);
-	float fmval[2];
-	UI_view2d_region_to_view(&ar->v2d, event->mval[0], event->mval[1], &fmval[0], &fmval[1]);
-
-	if (drag->type == WM_DRAG_ID) {
-		ID *id = drag->poin;
-		if (GS(id->name) == ID_MA) {
-			/* Ensure item under cursor is valid drop target */
-			TreeElement *te = outliner_dropzone_find(soops, fmval, true);
-			return (te && te->idcode == ID_OB && TREESTORE(te)->type == 0);
-		}
-	}
-	return 0;
+	/* Ensure item under cursor is valid drop target */
+	Material *ma = (Material *)WM_drag_ID(drag, ID_MA);
+	return (ma && (outliner_ID_drop_find(C, event, ID_OB) != NULL));
 }
 
-static void material_drop_copy(wmDrag *drag, wmDropBox *drop)
+static int material_drop_invoke(bContext *C, wmOperator *UNUSED(op), const wmEvent *event)
 {
-	ID *id = drag->poin;
-
-	RNA_string_set(drop->ptr, "material", id->name + 2);
-}
-
-static int material_drop_invoke(bContext *C, wmOperator *op, const wmEvent *event)
-{
-	Material *ma = NULL;
-	Object *ob = NULL;
 	Main *bmain = CTX_data_main(C);
-	SpaceOops *soops = CTX_wm_space_outliner(C);
-	ARegion *ar = CTX_wm_region(C);
-	TreeElement *te = NULL;
-	char mat_name[MAX_ID_NAME - 2];
-	float fmval[2];
-
-	UI_view2d_region_to_view(&ar->v2d, event->mval[0], event->mval[1], &fmval[0], &fmval[1]);
-
-	/* Find object hovered over */
-	te = outliner_dropzone_find(soops, fmval, true);
-
-	if (te) {
-		RNA_string_set(op->ptr, "object", te->name);
-		ob = (Object *)BKE_libblock_find_name(bmain, ID_OB, te->name);
+	Object *ob = (Object *)outliner_ID_drop_find(C, event, ID_OB);
+	Material *ma = (Material *)WM_drag_ID_from_event(event, ID_MA);
 
-		RNA_string_get(op->ptr, "material", mat_name);
-		ma = (Material *)BKE_libblock_find_name(bmain, ID_MA, mat_name);
-
-		if (ELEM(NULL, ob, ma)) {
-			return OPERATOR_CANCELLED;
-		}
-
-		assign_material(bmain, ob, ma, ob->totcol + 1, BKE_MAT_ASSIGN_USERPREF);
+	if (ELEM(NULL, ob, ma)) {
+		return OPERATOR_CANCELLED;
+	}
 
-		WM_event_add_notifier(C, NC_SPACE | ND_SPACE_VIEW3D, CTX_wm_view3d(C));
-		WM_event_add_notifier(C, NC_MATERIAL | ND_SHADING_LINKS, ma);
+	assign_material(bmain, ob, ma, ob->totcol + 1, BKE_MAT_ASSIGN_USERPREF);
 
-		return OPERATOR_FINISHED;
-	}
+	WM_event_add_notifier(C, NC_SPACE | ND_SPACE_VIEW3D, CTX_wm_view3d(C));
+	WM_event_add_notifier(C, NC_MATERIAL | ND_SHADING_LINKS, ma);
 
-	return OPERATOR_CANCELLED;
+	return OPERATOR_FINISHED;
 }
 
 void OUTLINER_OT_material_drop(wmOperatorType *ot)
@@ -640,80 +538,28 @@ void OUTLINER_OT_material_drop(wmOperatorType *ot)
 
 	/* flags */
 	ot->flag = OPTYPE_REGISTER | OPTYPE_UNDO | OPTYPE_INTERNAL;
-
-	/* properties */
-	RNA_def_string(ot->srna, "object", "Object", MAX_ID_NAME, "Object", "Target Object");
-	RNA_def_string(ot->srna, "material", "Material", MAX_ID_NAME, "Material", "Target Material");
 }
 
 /* ******************** Collection Drop Operator *********************** */
 
 static bool collection_drop_poll(bContext *C, wmDrag *drag, const wmEvent *event, const char **UNUSED(tooltip))
 {
-	ARegion *ar = CTX_wm_region(C);
-	SpaceOops *soops = CTX_wm_space_outliner(C);
-	float fmval[2];
-	UI_view2d_region_to_view(&ar->v2d, event->mval[0], event->mval[1], &fmval[0], &fmval[1]);
+	Object *ob = (Object *)WM_drag_ID(drag, ID_OB);
+	Collection *collection = (Collection *)WM_drag_ID(drag, ID_GR);
 
-	if (drag->type == WM_DRAG_ID) {
-		ID *id = drag->poin;
-		if (ELEM(GS(id->name), ID_OB, ID_GR)) {
-			/* Ensure item under cursor is valid drop target */
-			TreeElement *te = outliner_dropzone_find(soops, fmval, true);
-			return (te && outliner_is_collection_tree_element(te));
-		}
+	if (ob || collection) {
+		TreeElement *te = outliner_drop_find(C, event);
+		return (te && outliner_is_collection_tree_element(te));
 	}
-	return 0;
-}
-
-static void collection_drop_copy(wmDrag *drag, wmDropBox *drop)
-{
-	ID *id = drag->poin;
-	RNA_string_set(drop->ptr, "child", id->name + 2);
-}
-
-static int collection_drop_exec(bContext *UNUSED(C), wmOperator *UNUSED(op))
-{
-	/* TODO: implement */
-#if 0
-	Object *par = NULL, *ob = NULL;
-	Main *bmain = CTX_data_main(C);
-	Scene *scene = CTX_data_scene(C);
-	int partype = -1;
-	char parname[MAX_ID_NAME], childname[MAX_ID_NAME];
-
-	RNA_string_get(op->ptr, "parent", parname);
-	par = (Object *)BKE_libblock_find_name(ID_OB, parname);
-	RNA_string_get(op->ptr, "child", childname);
-	ob = (Object *)BKE_libblock_find_name(ID_OB, childname);
-
-	if (ID_IS_LINKED(ob)) {
-		BKE_report(op->reports, RPT_INFO, "Can't edit library linked object");
-		return OPERATOR_CANCELLED;
+	else {
+		return false;
 	}
-
-	ED_object_parent_set(op->reports, C, scene, ob, par, partype, false, false, NULL);
-
-	DEG_relations_tag_update(bmain);
-	WM_event_add_notifier(C, NC_OBJECT | ND_TRANSFORM, NULL);
-	WM_event_add_notifier(C, NC_OBJECT | ND_PARENT, NULL);
-#endif
-
-	return OPERATOR_FINISHED;
 }
 
-static int collection_drop_invoke(bContext *C, wmOperator *op, const wmEvent *event)
+static int collection_drop_invoke(bContext *C, wmOperator *UNUSED(op), const wmEvent *event)
 {
-	SpaceOops *soops = CTX_wm_space_outliner(C);
-	ARegion *ar = CTX_wm_region(C);
 	Main *bmain = CTX_data_main(C);
-	char childname[MAX_ID_NAME];
-	float fmval[2];
-
-	UI_view2d_region_to_view(&ar->v2d, event->mval[0], event->mval[1], &fmval[0], &fmval[1]);
-
-	/* Find object hovered over */
-	TreeElement *te = outliner_dropzone_find(soops, fmval, true);
+	TreeElement *te = outliner_drop_find(C, event);
 
 	if (!te || !outliner_is_collection_tree_element(te)) {
 		return OPERATOR_CANCELLED;
@@ -724,9 +570,11 @@ static int collection_drop_invoke(bContext *C, wmOperator *op, const wmEvent *ev
 	// TODO: don't use scene, makes no sense anymore
 	// TODO: move rather than link, change hover text
 	Scene *scene = BKE_scene_find_from_collection(bmain, collection);
-	BLI_assert(scene);
-	RNA_string_get(op->ptr, "child", childname);
-	Object *ob = (Object *)BKE_libblock_find_name(bmain, ID_OB, childname);
+	Object *ob = (Object *)WM_drag_ID_from_event(event, ID_OB);
+	if (ELEM(NULL, ob, scene, collection)) {
+		return OPERATOR_CANCELLED;
+	}
+
 	BKE_collection_object_add(bmain, collection, ob);
 
 	DEG_id_tag_update(&collection->id, DEG_TAG_COPY_ON_WRITE);
@@ -745,16 +593,10 @@ void OUTLINER_OT_collection_drop(wmOperatorType *ot)
 
 	/* api callbacks */
 	ot->invoke = collection_drop_invoke;
-	ot->exec = collection_drop_exec;
-
 	ot->poll = ED_operator_outliner_active;
 
 	/* flags */
 	ot->flag = OPTYPE_REGISTER | OPTYPE_UNDO | OPTYPE_INTERNAL;
-
-	/* properties */
-	RNA_def_string(ot->srna, "child", "Object", MAX_ID_NAME, "Child", "Child Object");
-	RNA_def_string(ot->srna, "parent", "Collection", MAX_ID_NAME, "Parent", "Parent Collection");
 }
 
 /* ********************* Outliner Drag Operator ******************** */
@@ -1107,9 +949,9 @@ void outliner_dropboxes(void)
 {
 	ListBase *lb = WM_dropboxmap_find("Outliner", SPACE_OUTLINER, RGN_TYPE_WINDOW);
 
-	WM_dropbox_add(lb, "OUTLINER_OT_parent_drop", parent_drop_poll, parent_drop_copy);
-	WM_dropbox_add(lb, "OUTLINER_OT_parent_clear", parent_clear_poll, parent_clear_copy);
-	WM_dropbox_add(lb, "OUTLINER_OT_scene_drop", scene_drop_poll, scene_drop_copy);
-	WM_dropbox_add(lb, "OUTLINER_OT_material_drop", material_drop_poll, material_drop_copy);
-	WM_dropbox_add(lb, "OUTLINER_OT_collection_drop", collection_drop_poll, collection_drop_copy);
+	WM_dropbox_add(lb, "OUTLINER_OT_parent_drop", parent_drop_poll, NULL);
+	WM_dropbox_add(lb, "OUTLINER_OT_parent_clear", parent_clear_poll, NULL);
+	WM_dropbox_add(lb, "OUTLINER_OT_scene_drop", scene_drop_poll, NULL);
+	WM_dropbox_add(lb, "OUTLINER_OT_material_drop", material_drop_poll, NULL);
+	WM_dropbox_add(lb, "OUTLINER_OT_collection_drop", collection_drop_poll, NULL);
 }