source/blender/editors/interface/interface_drag.cc

@@ -70,7 +70,7 @@ void UI_but_drag_set_path(uiBut *but, const char *path)
   if (but->dragflag & UI_BUT_DRAGPOIN_FREE) {
     WM_drag_data_free(but->dragtype, but->dragpoin);
   }
-  but->dragpoin = WM_drag_create_path_data(path);
+  but->dragpoin = WM_drag_create_path_data(&path, 1);
   but->dragflag |= UI_BUT_DRAGPOIN_FREE;
 }
 

source/blender/editors/io/io_obj.c

@@ -535,7 +535,7 @@ bool obj_file_drop_poll(bContext *UNUSED(C), wmDrag *drag, const wmEvent *UNUSED
   if (drag->type == WM_DRAG_PATH) {
     const eFileSel_File_Types file_type = WM_drag_get_path_file_type(drag);
     if (file_type == FILE_TYPE_OBJECT_IO &&
-        BLI_path_extension_check(WM_drag_get_path(drag), ".obj")) {
+        BLI_path_extension_check(WM_drag_get_paths(drag)[0], ".obj")) {
       return true;
     }
   }

source/blender/editors/io/io_utils.c

@@ -55,24 +55,27 @@ void skip_save_import_paths_props(wmOperatorType *ot, const eFileSel_Flag flag)
 
 void files_drop_copy(bContext *UNUSED(C), wmDrag *drag, wmDropBox *drop)
 {
+  const char **paths = WM_drag_get_paths(drag);
+  RNA_string_set(drop->ptr, "filepath", paths[0]);
 
-  RNA_string_set(drop->ptr, "filepath", WM_drag_get_path(drag));
-
-  // TODO(@guishe): Add support for multiple drag&drop files import
   char dir[FILE_MAX], file[FILE_MAX];
-  BLI_split_dirfile(WM_drag_get_path(drag), dir, file, sizeof(dir), sizeof(file));
+  BLI_split_dirfile(paths[0], dir, file, sizeof(dir), sizeof(file));
 
   RNA_string_set(drop->ptr, "directory", dir);
-
   RNA_collection_clear(drop->ptr, "files");
-  PointerRNA itemptr;
-  RNA_collection_add(drop->ptr, "files", &itemptr);
-  RNA_string_set(&itemptr, "name", file);
+
+  const int path_count = WM_drag_get_path_count(drag);
+  for (int i = 0; i < path_count; i++) {
+    BLI_split_dirfile(paths[i], dir, file, sizeof(dir), sizeof(file));
+    PointerRNA itemptr;
+    RNA_collection_add(drop->ptr, "files", &itemptr);
+    RNA_string_set(&itemptr, "name", file);
+  }
 }
 
 void file_drop_copy(bContext *UNUSED(C), wmDrag *drag, wmDropBox *drop)
 {
-  RNA_string_set(drop->ptr, "filepath", WM_drag_get_path(drag));
+  RNA_string_set(drop->ptr, "filepath", WM_drag_get_paths(drag)[0]);
 }
 
 void file_drop_info_draw(bContext *C, wmOperator *op, int icon)

source/blender/editors/screen/screen_ops.c

@@ -4564,7 +4564,7 @@ static void screen_animation_region_tag_redraw(
   ED_region_tag_redraw(region);
 }
 
-//#define PROFILE_AUDIO_SYNCH
+// #define PROFILE_AUDIO_SYNCH
 
 static int screen_animation_step_invoke(bContext *C, wmOperator *UNUSED(op), const wmEvent *event)
 {
@@ -5756,7 +5756,7 @@ static bool blend_file_drop_poll(bContext *UNUSED(C), wmDrag *drag, const wmEven
 static void blend_file_drop_copy(bContext *UNUSED(C), wmDrag *drag, wmDropBox *drop)
 {
   /* copy drag path to properties */
-  RNA_string_set(drop->ptr, "filepath", WM_drag_get_path(drag));
+  RNA_string_set(drop->ptr, "filepath", WM_drag_get_paths(drag)[0]);
 }
 
 void ED_keymap_screen(wmKeyConfig *keyconf)

source/blender/editors/space_clip/space_clip.cc

@@ -527,7 +527,7 @@ static void clip_drop_copy(bContext * /*C*/, wmDrag *drag, wmDropBox *drop)
   PointerRNA itemptr;
   char dir[FILE_MAX], file[FILE_MAX];
 
-  BLI_split_dirfile(WM_drag_get_path(drag), dir, file, sizeof(dir), sizeof(file));
+  BLI_split_dirfile(WM_drag_get_paths(drag)[0], dir, file, sizeof(dir), sizeof(file));
 
   RNA_string_set(drop->ptr, "directory", dir);
 

source/blender/editors/space_console/space_console.c

@@ -172,7 +172,7 @@ static bool path_drop_poll(bContext *UNUSED(C), wmDrag *drag, const wmEvent *UNU
 static void path_drop_copy(bContext *UNUSED(C), wmDrag *drag, wmDropBox *drop)
 {
   char pathname[FILE_MAX + 2];
-  BLI_snprintf(pathname, sizeof(pathname), "\"%s\"", WM_drag_get_path(drag));
+  BLI_snprintf(pathname, sizeof(pathname), "\"%s\"", WM_drag_get_paths(drag)[0]);
   RNA_string_set(drop->ptr, "text", pathname);
 }
 

source/blender/editors/space_file/space_file.c

@@ -783,7 +783,7 @@ static bool filepath_drop_poll(bContext *C, wmDrag *drag, const wmEvent *UNUSED(
 
 static void filepath_drop_copy(bContext *UNUSED(C), wmDrag *drag, wmDropBox *drop)
 {
-  RNA_string_set(drop->ptr, "filepath", WM_drag_get_path(drag));
+  RNA_string_set(drop->ptr, "filepath", WM_drag_get_paths(drag)[0]);
 }
 
 /* region dropbox definition */

source/blender/editors/space_image/space_image.c

@@ -268,7 +268,7 @@ static bool image_drop_poll(bContext *C, wmDrag *drag, const wmEvent *event)
 static void image_drop_copy(bContext *UNUSED(C), wmDrag *drag, wmDropBox *drop)
 {
   /* copy drag path to properties */
-  RNA_string_set(drop->ptr, "filepath", WM_drag_get_path(drag));
+  RNA_string_set(drop->ptr, "filepath", WM_drag_get_paths(drag)[0]);
 }
 
 /* area+region dropbox definition */

source/blender/editors/space_node/space_node.cc

@@ -711,7 +711,7 @@ static void node_id_path_drop_copy(bContext * /*C*/, wmDrag *drag, wmDropBox *dr
     return;
   }
 
-  const char *path = WM_drag_get_path(drag);
+  const char *path = WM_drag_get_paths(drag)[0];
   if (path) {
     RNA_string_set(drop->ptr, "filepath", path);
     RNA_struct_property_unset(drop->ptr, "name");

source/blender/editors/space_sequencer/sequencer_drag_drop.c

@@ -247,7 +247,7 @@ static void sequencer_drop_copy(bContext *C, wmDrag *drag, wmDropBox *drop)
     return;
   }
 
-  const char *path = WM_drag_get_path(drag);
+  const char *path = WM_drag_get_paths(drag)[0];
   /* Path dropped. */
   if (path) {
     if (RNA_struct_find_property(drop->ptr, "filepath")) {
@@ -335,7 +335,7 @@ static void get_drag_path(wmDrag *drag, char r_path[FILE_MAX])
     BLI_path_abs(r_path, BKE_main_blendfile_path_from_global());
   }
   else {
-    BLI_strncpy(r_path, WM_drag_get_path(drag), FILE_MAX);
+    BLI_strncpy(r_path, WM_drag_get_paths(drag)[0], FILE_MAX);
   }
 }
 

source/blender/editors/space_text/space_text.c

@@ -312,7 +312,7 @@ static bool text_drop_poll(bContext *UNUSED(C), wmDrag *drag, const wmEvent *UNU
 static void text_drop_copy(bContext *UNUSED(C), wmDrag *drag, wmDropBox *drop)
 {
   /* copy drag path to properties */
-  RNA_string_set(drop->ptr, "filepath", WM_drag_get_path(drag));
+  RNA_string_set(drop->ptr, "filepath", WM_drag_get_paths(drag)[0]);
 }
 
 static bool text_drop_paste_poll(bContext *UNUSED(C), wmDrag *drag, const wmEvent *UNUSED(event))

source/blender/editors/space_view3d/space_view3d.cc

@@ -903,7 +903,7 @@ static void view3d_id_path_drop_copy(bContext * /*C*/, wmDrag *drag, wmDropBox *
     RNA_struct_property_unset(drop->ptr, "filepath");
     return;
   }
-  const char *path = WM_drag_get_path(drag);
+  const char *path = WM_drag_get_paths(drag)[0];
   if (path) {
     RNA_string_set(drop->ptr, "filepath", path);
     RNA_struct_property_unset(drop->ptr, "image");

source/blender/windowmanager/WM_api.h

@@ -1445,13 +1445,15 @@ const ListBase *WM_drag_asset_list_get(const wmDrag *drag);
 
 const char *WM_drag_get_item_name(struct wmDrag *drag);
 
-/* Path drag and drop. */
+/* Paths drag and drop. */
 /**
- * \param path: The path to drag. Value will be copied into the drag data so the passed string may
- *              be destructed.
+ * \param paths: The paths to drag. Value will be copied into the drag data so the passed strings
+ * may be destructed. Only paths that share the same extension of the first file will be copied.
+ * \param path_count: the number of paths in #paths
  */
-wmDragPath *WM_drag_create_path_data(const char *path);
-const char *WM_drag_get_path(const wmDrag *drag);
+wmDragPath *WM_drag_create_path_data(const char **paths, int path_count);
+const char **WM_drag_get_paths(const wmDrag *drag);
+const int WM_drag_get_path_count(const wmDrag *drag);
 /**
  * Note that even though the enum return type uses bit-flags, this should never have multiple
  * type-bits set, so `ELEM()` like comparison is possible.

source/blender/windowmanager/WM_types.h

@@ -1133,7 +1133,9 @@ typedef struct wmDragAssetListItem {
 } wmDragAssetListItem;
 
 typedef struct wmDragPath {
-  char *path;
+  char **paths;
+  char *tooltip;
+  int path_count;
   /* Note that even though the enum type uses bit-flags, this should never have multiple type-bits
    * set, so `ELEM()` like comparison is possible. */
   int file_type; /* eFileSel_File_Types */

source/blender/windowmanager/intern/wm_dragdrop.cc

@@ -750,29 +750,70 @@ const ListBase *WM_drag_asset_list_get(const wmDrag *drag)
   return &drag->asset_items;
 }
 
-wmDragPath *WM_drag_create_path_data(const char *path)
+wmDragPath *WM_drag_create_path_data(const char **paths, int path_count)
 {
   wmDragPath *path_data = MEM_new<wmDragPath>("wmDragPath");
-  path_data->path = BLI_strdup(path);
-  path_data->file_type = ED_path_extension_type(path);
+
+  const char *ext = BLI_path_extension(paths[0]);
+
+  int valid_path_count = 1;
+  for (int i = 1; i < path_count; i++) {
+    if ((ext == nullptr && BLI_path_extension(paths[i]) == nullptr) ||
+        (ext != nullptr && BLI_path_extension_check(paths[i], ext))) {
+      valid_path_count++;
+    }
+  }
+  path_data->paths = (char **)MEM_mallocN(valid_path_count * sizeof(char *), "paths");
+
+  int path_index = 0;
+  for (int i = 0; i < path_count; i++) {
+    if ((ext == nullptr && BLI_path_extension(paths[i]) == nullptr) ||
+        (ext != nullptr && BLI_path_extension_check(paths[i], ext))) {
+      path_data->paths[path_index] = BLI_strdup(paths[i]);
+      path_index++;
+    }
+  }
+
+  path_data->file_type = ED_path_extension_type(paths[0]);
+  path_data->path_count = valid_path_count;
+  if (path_count == 1) {
+    path_data->tooltip = BLI_strdup(paths[0]);
+  }
+  else {
+    const char *tooltip = TIP_("Dragging %d %s files.");
+    path_data->tooltip = BLI_sprintfN(tooltip, valid_path_count, ext);
+  }
   return path_data;
 }
 
 static void wm_drag_free_path_data(wmDragPath **path_data)
 {
-  MEM_freeN((*path_data)->path);
+  for (int i = 0; i < (*path_data)->path_count; i++) {
+    MEM_freeN((*path_data)->paths[i]);
+  }
+  MEM_freeN((*path_data)->paths);
+  MEM_freeN((*path_data)->tooltip);
   MEM_delete(*path_data);
   *path_data = nullptr;
 }
 
-const char *WM_drag_get_path(const wmDrag *drag)
+const char **WM_drag_get_paths(const wmDrag *drag)
 {
   if (drag->type != WM_DRAG_PATH) {
     return nullptr;
   }
 
   const wmDragPath *path_data = static_cast<const wmDragPath *>(drag->poin);
-  return path_data->path;
+  return const_cast<const char **>(path_data->paths);
+}
+const int WM_drag_get_path_count(const wmDrag *drag)
+{
+  if (drag->type != WM_DRAG_PATH) {
+    return 0;
+  }
+
+  const wmDragPath *path_data = static_cast<const wmDragPath *>(drag->poin);
+  return path_data->path_count;
 }
 
 int WM_drag_get_path_file_type(const wmDrag *drag)
@@ -836,7 +877,7 @@ const char *WM_drag_get_item_name(wmDrag *drag)
     }
     case WM_DRAG_PATH: {
       const wmDragPath *path_drag_data = static_cast<const wmDragPath *>(drag->poin);
-      return path_drag_data->path;
+      return path_drag_data->tooltip;
     }
     case WM_DRAG_NAME:
       return static_cast<const char *>(drag->poin);

source/blender/windowmanager/intern/wm_window.c

@@ -1487,11 +1487,10 @@ static bool ghost_event_proc(GHOST_EventHandle evt, GHOST_TUserDataPtr C_void_pt
         if (ddd->dataType == GHOST_kDragnDropTypeFilenames) {
           GHOST_TStringArray *stra = ddd->data;
 
-          for (int a = 0; a < stra->count; a++) {
-            printf("drop file %s\n", stra->strings[a]);
+          if (stra->count > 0) {
             /* try to get icon type from extension */
-            int icon = ED_file_extension_icon((char *)stra->strings[a]);
-            wmDragPath *path_data = WM_drag_create_path_data((char *)stra->strings[a]);
+            int icon = ED_file_extension_icon((char *)stra->strings[0]);
+            wmDragPath *path_data = WM_drag_create_path_data((char **)stra->strings, stra->count);
             WM_event_start_drag(C, icon, WM_DRAG_PATH, path_data, 0.0, WM_DRAG_NOP);
             /* void poin should point to string, it makes a copy */
             break; /* only one drop element supported now */