Fix T73049: Drag & drop on overlapping panels behaves incorrectly

Reviewers: brecht, Severin

Differential Revision: https://developer.blender.org/D7024

4 files changed, 47 insertions, 15 deletions

diff --git a/source/blender/editors/include/ED_screen.h b/source/blender/editors/include/ED_screen.h
index 1dd40f27fbb..0785b0e97f7 100644
--- a/source/blender/editors/include/ED_screen.h
+++ b/source/blender/editors/include/ED_screen.h
@@ -431,6 +431,7 @@ int ED_region_generic_tools_region_snap_size(const struct ARegion *region, int s
 bool ED_region_overlap_isect_x(const ARegion *region, const int event_x);
 bool ED_region_overlap_isect_y(const ARegion *region, const int event_y);
 bool ED_region_overlap_isect_xy(const ARegion *region, const int event_xy[2]);
+bool ED_region_overlap_isect_any_xy(const ScrArea *area, const int event_xy[2]);
 bool ED_region_overlap_isect_x_with_margin(const ARegion *region,
                                            const int event_x,
                                            const int margin);
diff --git a/source/blender/editors/screen/area_query.c b/source/blender/editors/screen/area_query.c
index f8a6b301911..2cccd9a2ba5 100644
--- a/source/blender/editors/screen/area_query.c
+++ b/source/blender/editors/screen/area_query.c
@@ -61,6 +61,18 @@ bool ED_region_overlap_isect_xy(const ARegion *region, const int event_xy[2])
           ED_region_overlap_isect_y(region, event_xy[1]));
 }
 
+bool ED_region_overlap_isect_any_xy(const ScrArea *area, const int event_xy[2])
+{
+  LISTBASE_FOREACH (ARegion *, region, &area->regionbase) {
+    if (ED_region_is_overlap(area->spacetype, region->regiontype)) {
+      if (ED_region_overlap_isect_xy(region, event_xy)) {
+        return true;
+      }
+    }
+  }
+  return false;
+}
+
 bool ED_region_panel_category_gutter_calc_rect(const ARegion *region, rcti *r_ar_gutter)
 {
   *r_ar_gutter = region->winrct;
diff --git a/source/blender/editors/space_image/space_image.c b/source/blender/editors/space_image/space_image.c
index dc546e5baf5..42a8a746eef 100644
--- a/source/blender/editors/space_image/space_image.c
+++ b/source/blender/editors/space_image/space_image.c
@@ -262,18 +262,22 @@ static void image_keymap(struct wmKeyConfig *keyconf)
 }
 
 /* dropboxes */
-static bool image_drop_poll(bContext *UNUSED(C),
+static bool image_drop_poll(bContext *C,
                             wmDrag *drag,
-                            const wmEvent *UNUSED(event),
+                            const wmEvent *event,
                             const char **UNUSED(tooltip))
 {
+  ScrArea *area = CTX_wm_area(C);
+  if (ED_region_overlap_isect_any_xy(area, &event->x)) {
+    return false;
+  }
   if (drag->type == WM_DRAG_PATH) {
     /* rule might not work? */
     if (ELEM(drag->icon, 0, ICON_FILE_IMAGE, ICON_FILE_MOVIE, ICON_FILE_BLANK)) {
-      return 1;
+      return true;
     }
   }
-  return 0;
+  return false;
 }
 
 static void image_drop_copy(wmDrag *drag, wmDropBox *drop)
diff --git a/source/blender/editors/space_view3d/space_view3d.c b/source/blender/editors/space_view3d/space_view3d.c
index 8ec7d5a166b..020c58270fc 100644
--- a/source/blender/editors/space_view3d/space_view3d.c
+++ b/source/blender/editors/space_view3d/space_view3d.c
@@ -436,35 +436,50 @@ static void view3d_main_region_exit(wmWindowManager *wm, ARegion *region)
   ED_view3d_stop_render_preview(wm, region);
 }
 
-static bool view3d_ob_drop_poll(bContext *UNUSED(C),
+static bool view3d_drop_id_in_main_region_poll(bContext *C,
+                                               wmDrag *drag,
+                                               const wmEvent *event,
+                                               ID_Type id_type)
+{
+  ScrArea *area = CTX_wm_area(C);
+  if (ED_region_overlap_isect_any_xy(area, &event->x)) {
+    return false;
+  }
+  return WM_drag_ID(drag, id_type) != NULL;
+}
+
+static bool view3d_ob_drop_poll(bContext *C,
                                 wmDrag *drag,
-                                const wmEvent *UNUSED(event),
+                                const wmEvent *event,
                                 const char **UNUSED(tooltip))
 {
-  return WM_drag_ID(drag, ID_OB) != NULL;
+  return view3d_drop_id_in_main_region_poll(C, drag, event, ID_OB);
 }
 
-static bool view3d_collection_drop_poll(bContext *UNUSED(C),
+static bool view3d_collection_drop_poll(bContext *C,
                                         wmDrag *drag,
-                                        const wmEvent *UNUSED(event),
+                                        const wmEvent *event,
                                         const char **UNUSED(tooltip))
 {
-  return WM_drag_ID(drag, ID_GR) != NULL;
+  return view3d_drop_id_in_main_region_poll(C, drag, event, ID_GR);
 }
 
-static bool view3d_mat_drop_poll(bContext *UNUSED(C),
+static bool view3d_mat_drop_poll(bContext *C,
                                  wmDrag *drag,
-                                 const wmEvent *UNUSED(event),
+                                 const wmEvent *event,
                                  const char **UNUSED(tooltip))
 {
-  return WM_drag_ID(drag, ID_MA) != NULL;
+  return view3d_drop_id_in_main_region_poll(C, drag, event, ID_MA);
 }
 
-static bool view3d_ima_drop_poll(bContext *UNUSED(C),
+static bool view3d_ima_drop_poll(bContext *C,
                                  wmDrag *drag,
-                                 const wmEvent *UNUSED(event),
+                                 const wmEvent *event,
                                  const char **UNUSED(tooltip))
 {
+  if (ED_region_overlap_isect_any_xy(CTX_wm_area(C), &event->x)) {
+    return false;
+  }
   if (drag->type == WM_DRAG_PATH) {
     /* rule might not work? */
     return (ELEM(drag->icon, 0, ICON_FILE_IMAGE, ICON_FILE_MOVIE));