Cleanup outliner_dropzone code

 * deduplicated a bunch of code and moved it into outliner_dropzone_find()
 * moved all the per-dropzone checks into the poll functions
 * one functional change, disable drop parenting on self & self->parent

The basic assumption: if poll() == true then outliner_dropzone_find() will return a valid TreeElement

3 files changed, 79 insertions, 156 deletions

diff --git a/source/blender/editors/space_outliner/outliner_edit.c b/source/blender/editors/space_outliner/outliner_edit.c
index 1e67e099508..0a1d3a63f2c 100644
--- a/source/blender/editors/space_outliner/outliner_edit.c
+++ b/source/blender/editors/space_outliner/outliner_edit.c
@@ -113,6 +113,37 @@ static void outliner_open_reveal(SpaceOops *soops, ListBase *lb, TreeElement *te
 }
 #endif
 
+static TreeElement *outliner_dropzone_element(const SpaceOops *soops, TreeElement *te, const float fmval[2], const int children)
+{
+	if ((fmval[1] > te->ys) && (fmval[1] < (te->ys + UI_UNIT_Y))) {
+		/* name and first icon */
+		if ((fmval[0] > te->xs + UI_UNIT_X) && (fmval[0] < te->xend))
+			return te;
+	}
+	/* Not it.  Let's look at its children. */
+	if (children && (TREESTORE(te)->flag & TSE_CLOSED) == 0 && (te->subtree.first)) {
+		for (te = te->subtree.first; te; te = te->next) {
+			TreeElement *te_valid = outliner_dropzone_element(soops, te, fmval, children);
+			if (te_valid)
+				return te_valid;
+		}
+	}
+	return NULL;
+}
+
+/* Used for drag and drop parenting */
+TreeElement *outliner_dropzone_find(const SpaceOops *soops, const float fmval[2], const int children)
+{
+	TreeElement *te;
+
+	for (te = soops->tree.first; te; te = te->next) {
+		TreeElement *te_valid = outliner_dropzone_element(soops, te, fmval, children);
+		if (te_valid)
+			return te_valid;
+	}
+	return NULL;
+}
+
 /* ************************************************************** */
 /* Click Activated */
 
@@ -1447,36 +1478,6 @@ static int parent_drop_exec(bContext *C, wmOperator *op)
 	return OPERATOR_FINISHED;
 }
 
-/* Used for drag and drop parenting */
-TreeElement *outliner_dropzone_parent(bContext *C, const wmEvent *event, TreeElement *te, const float fmval[2])
-{
-	SpaceOops *soops = CTX_wm_space_outliner(C);
-	TreeStoreElem *tselem = TREESTORE(te);
-
-	if ((fmval[1] > te->ys) && (fmval[1] < (te->ys + UI_UNIT_Y))) {
-		/* name and first icon */
-		if ((fmval[0] > te->xs + UI_UNIT_X) && (fmval[0] < te->xend)) {
-			/* always makes active object */
-			if (te->idcode == ID_OB && tselem->type == 0) {
-				return te;
-			}
-			else {
-				return NULL;
-			}
-		}
-	}
-
-	/* Not it.  Let's look at its children. */
-	if ((tselem->flag & TSE_CLOSED) == 0 && (te->subtree.first)) {
-		for (te = te->subtree.first; te; te = te->next) {
-			TreeElement *te_valid;
-			te_valid = outliner_dropzone_parent(C, event, te, fmval);
-			if (te_valid) return te_valid;
-		}
-	}
-	return NULL;
-}
-
 static int parent_drop_invoke(bContext *C, wmOperator *op, const wmEvent *event)
 {
 	Object *par = NULL;
@@ -1486,7 +1487,6 @@ static int parent_drop_invoke(bContext *C, wmOperator *op, const wmEvent *event)
 	Main *bmain = CTX_data_main(C);
 	Scene *scene = NULL;
 	TreeElement *te = NULL;
-	TreeElement *te_found = NULL;
 	char childname[MAX_ID_NAME];
 	char parname[MAX_ID_NAME];
 	int partype = 0;
@@ -1495,13 +1495,10 @@ static int parent_drop_invoke(bContext *C, wmOperator *op, const wmEvent *event)
 	UI_view2d_region_to_view(&ar->v2d, event->mval[0], event->mval[1], &fmval[0], &fmval[1]);
 
 	/* Find object hovered over */
-	for (te = soops->tree.first; te; te = te->next) {
-		te_found = outliner_dropzone_parent(C, event, te, fmval);
-		if (te_found) break;
-	}
+	te = outliner_dropzone_find(soops, fmval, 1);
 
-	if (te_found) {
-		RNA_string_set(op->ptr, "parent", te_found->name);
+	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(ID_OB, childname);
@@ -1516,7 +1513,7 @@ static int parent_drop_invoke(bContext *C, wmOperator *op, const wmEvent *event)
 			return OPERATOR_CANCELLED;
 		}
 		
-		scene = (Scene *)outliner_search_back(soops, te_found, ID_SCE);
+		scene = (Scene *)outliner_search_back(soops, te, ID_SCE);
 
 		if (scene == NULL) {
 			/* currently outlier organized in a way, that if there's no parent scene
@@ -1651,44 +1648,6 @@ void OUTLINER_OT_parent_drop(wmOperatorType *ot)
 	RNA_def_enum(ot->srna, "type", prop_make_parent_types, 0, "Type", "");
 }
 
-int outliner_dropzone_parent_clear(bContext *C, const wmEvent *event, TreeElement *te, const float fmval[2])
-{
-	SpaceOops *soops = CTX_wm_space_outliner(C);
-	TreeStoreElem *tselem = TREESTORE(te);
-
-	/* Check for row */
-	if ((fmval[1] > te->ys) && (fmval[1] < (te->ys + UI_UNIT_Y))) {
-		/* Ignore drop on scene tree elements */
-		if ((fmval[0] > te->xs + UI_UNIT_X) && (fmval[0] < te->xend)) {
-			if ((te->idcode == ID_SCE) && 
-			    !ELEM3(tselem->type, TSE_R_LAYER_BASE, TSE_R_LAYER, TSE_R_PASS))
-			{
-				return 0;
-			}
-			// Other codes to ignore?
-		}
-		
-		/* Left or right of: (+), first icon, and name */
-		if ((fmval[0] < (te->xs + UI_UNIT_X)) || (fmval[0] > te->xend)) {
-			return 1;
-		}
-		else if (te->idcode != ID_OB || ELEM(tselem->type, TSE_MODIFIER_BASE, TSE_CONSTRAINT_BASE)) {
-			return 1;
-		}
-		
-		return 0;       // ID_OB, but mouse in undefined dropzone.
-	}
-
-	/* Not this row.  Let's look at its children. */
-	if ((tselem->flag & TSE_CLOSED) == 0 && (te->subtree.first)) {
-		for (te = te->subtree.first; te; te = te->next) {
-			if (outliner_dropzone_parent_clear(C, event, te, fmval)) 
-				return 1;
-		}
-	}
-	return 0;
-}
-
 static int parent_clear_invoke(bContext *C, wmOperator *op, const wmEvent *UNUSED(event))
 {
 	Main *bmain = CTX_data_main(C);
@@ -1738,22 +1697,6 @@ void OUTLINER_OT_parent_clear(wmOperatorType *ot)
 	RNA_def_enum(ot->srna, "type", prop_clear_parent_types, 0, "Type", "");
 }
 
-TreeElement *outliner_dropzone_scene(bContext *C, const wmEvent *UNUSED(event), TreeElement *te, const float fmval[2])
-{
-	SpaceOops *soops = CTX_wm_space_outliner(C);
-	TreeStoreElem *tselem = TREESTORE(te);
-
-	if ((fmval[1] > te->ys) && (fmval[1] < (te->ys + UI_UNIT_Y))) {
-		/* name and first icon */
-		if ((fmval[0] > te->xs + UI_UNIT_X) && (fmval[0] < te->xend)) {
-			if (te->idcode == ID_SCE && tselem->type == 0) {
-				return te;
-			}
-		}
-	}
-	return NULL;
-}
-
 static int scene_drop_invoke(bContext *C, wmOperator *op, const wmEvent *event)
 {
 	Scene *scene = NULL;
@@ -1762,24 +1705,19 @@ static int scene_drop_invoke(bContext *C, wmOperator *op, const wmEvent *event)
 	ARegion *ar = CTX_wm_region(C);
 	Main *bmain = CTX_data_main(C);
 	TreeElement *te = NULL;
-	TreeElement *te_found = 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 */
-	for (te = soops->tree.first; te; te = te->next) {
-		te_found = outliner_dropzone_scene(C, event, te, fmval);
-		if (te_found)
-			break;
-	}
+	te = outliner_dropzone_find(soops, fmval, 0);
 
-	if (te_found) {
+	if (te) {
 		Base *base;
 
-		RNA_string_set(op->ptr, "scene", te_found->name);
-		scene = (Scene *)BKE_libblock_find_name(ID_SCE, te_found->name);
+		RNA_string_set(op->ptr, "scene", te->name);
+		scene = (Scene *)BKE_libblock_find_name(ID_SCE, te->name);
 
 		RNA_string_get(op->ptr, "object", obname);
 		ob = (Object *)BKE_libblock_find_name(ID_OB, obname);
@@ -1837,22 +1775,17 @@ static int material_drop_invoke(bContext *C, wmOperator *op, const wmEvent *even
 	SpaceOops *soops = CTX_wm_space_outliner(C);
 	ARegion *ar = CTX_wm_region(C);
 	TreeElement *te = NULL;
-	TreeElement *te_found = 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 */
-	for (te = soops->tree.first; te; te = te->next) {
-		te_found = outliner_dropzone_parent(C, event, te, fmval);
-		if (te_found)
-			break;
-	}
+	te = outliner_dropzone_find(soops, fmval, 1);
 
-	if (te_found) {
-		RNA_string_set(op->ptr, "object", te_found->name);
-		ob = (Object *)BKE_libblock_find_name(ID_OB, te_found->name);
+	if (te) {
+		RNA_string_set(op->ptr, "object", te->name);
+		ob = (Object *)BKE_libblock_find_name(ID_OB, te->name);
 
 		RNA_string_get(op->ptr, "material", mat_name);
 		ma = (Material *)BKE_libblock_find_name(ID_MA, mat_name);
diff --git a/source/blender/editors/space_outliner/outliner_intern.h b/source/blender/editors/space_outliner/outliner_intern.h
index a918357ced2..3ab412f0ddc 100644
--- a/source/blender/editors/space_outliner/outliner_intern.h
+++ b/source/blender/editors/space_outliner/outliner_intern.h
@@ -190,9 +190,7 @@ void group_toggle_renderability_cb(struct bContext *C, struct Scene *scene, Tree
 
 void item_rename_cb(struct bContext *C, struct Scene *scene, TreeElement *te, struct TreeStoreElem *tsep, struct TreeStoreElem *tselem);
 
-TreeElement *outliner_dropzone_parent(struct bContext *C, const struct wmEvent *event, struct TreeElement *te, const float fmval[2]);
-int outliner_dropzone_parent_clear(struct bContext *C, const struct wmEvent *event, struct TreeElement *te, const float fmval[2]);
-TreeElement *outliner_dropzone_scene(struct bContext *C, const struct wmEvent *event, struct TreeElement *te, const float fmval[2]);
+TreeElement *outliner_dropzone_find(const struct SpaceOops *soops, const float fmval[2], const int children);
 /* ...................................................... */
 
 void OUTLINER_OT_item_activate(struct wmOperatorType *ot);
diff --git a/source/blender/editors/space_outliner/space_outliner.c b/source/blender/editors/space_outliner/space_outliner.c
index 3849aaf78c1..76a3da23d57 100644
--- a/source/blender/editors/space_outliner/space_outliner.c
+++ b/source/blender/editors/space_outliner/space_outliner.c
@@ -94,7 +94,6 @@ static int outliner_parent_drop_poll(bContext *C, wmDrag *drag, const wmEvent *e
 {
 	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]);
 
@@ -102,25 +101,25 @@ static int outliner_parent_drop_poll(bContext *C, wmDrag *drag, const wmEvent *e
 		ID *id = (ID *)drag->poin;
 		if (GS(id->name) == ID_OB) {
 			/* Ensure item under cursor is valid drop target */
-			/* Find object hovered over */
-			for (te = soops->tree.first; te; te = te->next) {
-				TreeElement *te_valid;
-				te_valid = outliner_dropzone_parent(C, event, te, fmval);
-				if (te_valid) {
-					/* check that parent/child are both in the same scene */
-					Scene *scene = (Scene *)outliner_search_back(soops, te_valid, ID_SCE);
-
-					if (!scene) {
-						/* 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)
-						 */
-						return 1;
-					}
+			TreeElement *te = outliner_dropzone_find(soops, fmval, 1);
 
-					if (scene && BKE_scene_base_find(scene, (Object *)id)) {
-						return 1;
-					}
+			if (te && te->idcode == ID_OB && TREESTORE(te)->type == 0) {
+				Scene *scene;
+				ID *te_id = TREESTORE(te)->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 || BKE_scene_base_find(scene, (Object *)id)) {
+					return 1;
 				}
 			}
 		}
@@ -147,19 +146,20 @@ static int outliner_parent_clear_poll(bContext *C, wmDrag *drag, const wmEvent *
 	if (drag->type == WM_DRAG_ID) {
 		ID *id = (ID *)drag->poin;
 		if (GS(id->name) == ID_OB) {
-			if (((Object *)id)->parent == NULL) {
-				return 0;
-			}
-			/* Ensure location under cursor is valid dropzone */
-			for (te = soops->tree.first; te; te = te->next) {
-				if (outliner_dropzone_parent_clear(C, event, te, fmval)) return 1;
-			}
-			/* Check if mouse cursor is below the tree */
-			te = soops->tree.last;
-			while (((te->flag & TE_LAZY_CLOSED) == 0) && (te->subtree.last)) {
-				te = te->subtree.last;
+			if (((Object *)id)->parent) {
+				if ((te = outliner_dropzone_find(soops, fmval, 1))) {
+					TreeStoreElem *tselem = TREESTORE(te);
+
+					switch (te->idcode) {
+						case ID_SCE:
+							return (ELEM3(tselem->type, TSE_R_LAYER_BASE, TSE_R_LAYER, TSE_R_PASS));
+						case ID_OB:
+							return (ELEM(tselem->type, TSE_MODIFIER_BASE, TSE_CONSTRAINT_BASE));
+						/* Other codes to ignore? */
+					}
+				}
+				return (te == NULL);
 			}
-			if (fmval[1] < te->ys) return 1;
 		}
 	}
 	return 0;
@@ -180,7 +180,6 @@ static int outliner_scene_drop_poll(bContext *C, wmDrag *drag, const wmEvent *ev
 {
 	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]);
 
@@ -188,11 +187,8 @@ static int outliner_scene_drop_poll(bContext *C, wmDrag *drag, const wmEvent *ev
 		ID *id = (ID *)drag->poin;
 		if (GS(id->name) == ID_OB) {
 			/* Ensure item under cursor is valid drop target */
-			/* Find object hovered over */
-			for (te = soops->tree.first; te; te = te->next) {
-				if (outliner_dropzone_scene(C, event, te, fmval))
-					return 1;
-			}
+			TreeElement *te = outliner_dropzone_find(soops, fmval, 0);
+			return (te && te->idcode == ID_SCE && TREESTORE(te)->type == 0);
 		}
 	}
 	return 0;
@@ -209,7 +205,6 @@ static int outliner_material_drop_poll(bContext *C, wmDrag *drag, const wmEvent
 {
 	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]);
 
@@ -217,11 +212,8 @@ static int outliner_material_drop_poll(bContext *C, wmDrag *drag, const wmEvent
 		ID *id = (ID *)drag->poin;
 		if (GS(id->name) == ID_MA) {
 			/* Ensure item under cursor is valid drop target */
-			/* Find object hovered over */
-			for (te = soops->tree.first; te; te = te->next) {
-				if (outliner_dropzone_parent(C, event, te, fmval))
-					return 1;
-			}
+			TreeElement *te = outliner_dropzone_find(soops, fmval, 1);
+			return (te && te->idcode == ID_OB && TREESTORE(te)->type == 0);
 		}
 	}
 	return 0;