Geometry Nodes: support creating import nodes when dropping file paths

Now import nodes are automatically created in Geometry Nodes when dropping
`.obj`, `.stl`, `.ply` and `.csv` files. Note that this is still hidden behind an
experimental feature flag.

Pull Request: https://projects.blender.org/blender/blender/pulls/135036

source/blender/editors/io/io_drop_import_file.cc

@@ -175,21 +175,7 @@ void WM_OT_drop_import_file(wmOperatorType *ot)
 
 static void drop_import_file_copy(bContext * /*C*/, wmDrag *drag, wmDropBox *drop)
 {
-  const auto paths = WM_drag_get_paths(drag);
-
-  char dir[FILE_MAX];
-  BLI_path_split_dir_part(paths[0].c_str(), dir, sizeof(dir));
-  RNA_string_set(drop->ptr, "directory", dir);
-
-  RNA_collection_clear(drop->ptr, "files");
-  for (const auto &path : paths) {
-    char file[FILE_MAX];
-    BLI_path_split_file_part(path.c_str(), file, sizeof(file));
-
-    PointerRNA itemptr{};
-    RNA_collection_add(drop->ptr, "files", &itemptr);
-    RNA_string_set(&itemptr, "name", file);
-  }
+  blender::ed::io::paths_to_operator_properties(drop->ptr, WM_drag_get_paths(drag));
 }
 
 static bool drop_import_file_poll(bContext *C, wmDrag *drag, const wmEvent * /*event*/)

source/blender/editors/io/io_utils.cc

@@ -111,4 +111,22 @@ Vector<std::string> paths_from_operator_properties(PointerRNA *ptr)
   }
   return paths;
 }
+
+void paths_to_operator_properties(PointerRNA *ptr, const Span<std::string> paths)
+{
+  char dir[FILE_MAX];
+  BLI_path_split_dir_part(paths[0].c_str(), dir, sizeof(dir));
+  RNA_string_set(ptr, "directory", dir);
+
+  RNA_collection_clear(ptr, "files");
+  for (const auto &path : paths) {
+    char file[FILE_MAX];
+    BLI_path_split_file_part(path.c_str(), file, sizeof(file));
+
+    PointerRNA itemptr{};
+    RNA_collection_add(ptr, "files", &itemptr);
+    RNA_string_set(&itemptr, "name", file);
+  }
+}
+
 }  // namespace blender::ed::io

source/blender/editors/io/io_utils.hh

@@ -29,4 +29,5 @@ bool poll_file_object_drop(const bContext *C, blender::bke::FileHandlerType *fh)
  * If the pointer has a `filepath` property is also returned as fallback.
  */
 Vector<std::string> paths_from_operator_properties(PointerRNA *ptr);
+void paths_to_operator_properties(PointerRNA *ptr, const Span<std::string> paths);
 }  // namespace blender::ed::io

source/blender/editors/space_node/node_add.cc

@@ -19,6 +19,7 @@
 #include "BLI_easing.h"
 #include "BLI_listbase.h"
 #include "BLI_math_geom.h"
+#include "BLI_string.h"
 
 #include "BLT_translation.hh"
 
@@ -701,7 +702,7 @@ struct NodeStackAnimationData {
   wmTimer *anim_timer;
 };
 
-static int node_add_file_modal(bContext *C, wmOperator *op, const wmEvent *event)
+static int node_add_nodes_modal(bContext *C, wmOperator *op, const wmEvent *event)
 {
   NodeStackAnimationData *data = static_cast<NodeStackAnimationData *>(op->customdata);
 
@@ -877,7 +878,7 @@ void NODE_OT_add_file(wmOperatorType *ot)
 
   /* callbacks */
   ot->exec = node_add_file_exec;
-  ot->modal = node_add_file_modal;
+  ot->modal = node_add_nodes_modal;
   ot->invoke = node_add_file_invoke;
   ot->poll = node_add_file_poll;
 
@@ -1033,6 +1034,115 @@ void NODE_OT_add_material(wmOperatorType *ot)
 
 /** \} */
 
+/* -------------------------------------------------------------------- */
+/** \name Add Import Node Operator
+ * \{ */
+
+static int node_add_import_node_exec(bContext *C, wmOperator *op)
+{
+  Main *bmain = CTX_data_main(C);
+  SpaceNode *snode = CTX_wm_space_node(C);
+  bNodeTree *ntree = snode->edittree;
+
+  const Vector<std::string> paths = ed::io::paths_from_operator_properties(op->ptr);
+
+  Vector<bNode *> new_nodes;
+  for (const StringRefNull path : paths) {
+    bNode *node = nullptr;
+    if (path.endswith(".csv")) {
+      node = add_node(*C, "GeometryNodeImportCSV", snode->runtime->cursor);
+    }
+    else if (path.endswith(".obj")) {
+      node = add_node(*C, "GeometryNodeImportOBJ", snode->runtime->cursor);
+    }
+    else if (path.endswith(".ply")) {
+      node = add_node(*C, "GeometryNodeImportPLY", snode->runtime->cursor);
+    }
+    else if (path.endswith(".stl")) {
+      node = add_node(*C, "GeometryNodeImportSTL", snode->runtime->cursor);
+    }
+
+    if (node) {
+      bNodeSocket &path_socket = node->input_by_identifier("Path");
+      BLI_assert(path_socket.type == SOCK_STRING);
+      auto *socket_data = static_cast<bNodeSocketValueString *>(path_socket.default_value);
+      STRNCPY(socket_data->value, path.c_str());
+      new_nodes.append(node);
+    }
+  }
+
+  if (new_nodes.is_empty()) {
+    return OPERATOR_CANCELLED;
+  }
+
+  node_deselect_all(*ntree);
+
+  for (const int i : new_nodes.index_range()) {
+    bNode *node = new_nodes[i];
+    node->flag |= NODE_SELECT;
+  }
+  bke::node_set_active(*ntree, *new_nodes[0]);
+
+  NodeStackAnimationData *data = MEM_new<NodeStackAnimationData>(__func__);
+  data->nodes = std::move(new_nodes);
+  data->anim_timer = WM_event_timer_add(CTX_wm_manager(C), CTX_wm_window(C), TIMER, 0.02);
+  op->customdata = data;
+  WM_event_add_modal_handler(C, op);
+
+  BKE_main_ensure_invariants(*bmain, ntree->id);
+
+  return OPERATOR_RUNNING_MODAL;
+}
+
+static int node_add_import_node_invoke(bContext *C, wmOperator *op, const wmEvent *event)
+{
+  ARegion *region = CTX_wm_region(C);
+  SpaceNode *snode = CTX_wm_space_node(C);
+
+  /* Convert mouse coordinates to v2d space. */
+  UI_view2d_region_to_view(&region->v2d,
+                           event->mval[0],
+                           event->mval[1],
+                           &snode->runtime->cursor[0],
+                           &snode->runtime->cursor[1]);
+
+  snode->runtime->cursor[0] /= UI_SCALE_FAC;
+  snode->runtime->cursor[1] /= UI_SCALE_FAC;
+
+  return node_add_import_node_exec(C, op);
+}
+
+static bool node_add_import_node_poll(bContext *C)
+{
+  const SpaceNode *snode = CTX_wm_space_node(C);
+  return ED_operator_node_editable(C) && snode->nodetree->type == NTREE_GEOMETRY;
+}
+
+void NODE_OT_add_import_node(wmOperatorType *ot)
+{
+  ot->name = "Add Import Node";
+  ot->description = "Add an import node to the node tree";
+  ot->idname = "NODE_OT_add_import_node";
+
+  ot->poll = node_add_import_node_poll;
+  ot->exec = node_add_import_node_exec;
+  ot->invoke = node_add_import_node_invoke;
+  ot->modal = node_add_nodes_modal;
+
+  ot->flag = OPTYPE_REGISTER | OPTYPE_UNDO | OPTYPE_INTERNAL;
+
+  PropertyRNA *prop;
+
+  prop = RNA_def_string_dir_path(
+      ot->srna, "directory", nullptr, FILE_MAX, "Directory", "Directory of the file");
+  RNA_def_property_flag(prop, PROP_HIDDEN | PROP_SKIP_SAVE);
+
+  prop = RNA_def_collection_runtime(ot->srna, "files", &RNA_OperatorFileListElement, "Files", "");
+  RNA_def_property_flag(prop, PROP_HIDDEN | PROP_SKIP_SAVE);
+}
+
+/** \} */
+
 /* -------------------------------------------------------------------- */
 /** \name Add Color Operator
  * \{ */

source/blender/editors/space_node/node_intern.hh

@@ -298,6 +298,7 @@ void NODE_OT_add_file(wmOperatorType *ot);
 void NODE_OT_add_mask(wmOperatorType *ot);
 void NODE_OT_add_material(wmOperatorType *ot);
 void NODE_OT_add_color(wmOperatorType *ot);
+void NODE_OT_add_import_node(wmOperatorType *ot);
 void NODE_OT_new_node_tree(wmOperatorType *ot);
 
 /* `node_group.cc` */

source/blender/editors/space_node/node_ops.cc

@@ -85,6 +85,7 @@ void node_operatortypes()
   WM_operatortype_append(NODE_OT_add_mask);
   WM_operatortype_append(NODE_OT_add_material);
   WM_operatortype_append(NODE_OT_add_color);
+  WM_operatortype_append(NODE_OT_add_import_node);
 
   WM_operatortype_append(NODE_OT_new_node_tree);
 

source/blender/editors/space_node/space_node.cc

@@ -60,6 +60,8 @@
 #include "WM_api.hh"
 #include "WM_types.hh"
 
+#include "io_utils.hh"
+
 #include "node_intern.hh" /* own include */
 
 using blender::float2;
@@ -857,6 +859,25 @@ static bool node_color_drop_poll(bContext *C, wmDrag *drag, const wmEvent * /*ev
   return (drag->type == WM_DRAG_COLOR) && !UI_but_active_drop_color(C);
 }
 
+static bool node_import_file_drop_poll(bContext * /*C*/, wmDrag *drag, const wmEvent * /*event*/)
+{
+  if (!U.experimental.use_new_file_import_nodes) {
+    return false;
+  }
+  if (drag->type != WM_DRAG_PATH) {
+    return false;
+  }
+  const blender::Span<std::string> paths = WM_drag_get_paths(drag);
+  for (const StringRef path : paths) {
+    if (path.endswith(".csv") || path.endswith(".obj") || path.endswith(".ply") ||
+        path.endswith(".stl"))
+    {
+      return true;
+    }
+  }
+  return false;
+}
+
 static void node_group_drop_copy(bContext *C, wmDrag *drag, wmDropBox *drop)
 {
   ID *id = WM_drag_get_local_ID_or_import_from_asset(C, drag, 0);
@@ -883,6 +904,11 @@ static void node_id_im_drop_copy(bContext *C, wmDrag *drag, wmDropBox *drop)
   }
 }
 
+static void node_import_file_drop_copy(bContext * /*C*/, wmDrag *drag, wmDropBox *drop)
+{
+  io::paths_to_operator_properties(drop->ptr, WM_drag_get_paths(drag));
+}
+
 /* this region dropbox definition */
 static void node_dropboxes()
 {
@@ -926,6 +952,12 @@ static void node_dropboxes()
                  nullptr);
   WM_dropbox_add(
       lb, "NODE_OT_add_color", node_color_drop_poll, UI_drop_color_copy, nullptr, nullptr);
+  WM_dropbox_add(lb,
+                 "NODE_OT_add_import_node",
+                 node_import_file_drop_poll,
+                 node_import_file_drop_copy,
+                 nullptr,
+                 nullptr);
 }
 
 /* ************* end drop *********** */