Nodes: Add modal keymap for Node link drag

This will add a proper modal keymap for the node link drag operator.
It allows the user to customize the keys used to start drag and so on.
Also it gets rid of the custom status bar message.

Differential Revision: https://developer.blender.org/D17190

release/scripts/presets/keyconfig/keymap_data/blender_default.py

@@ -6318,6 +6318,25 @@ def km_curve_pen_modal_map(_params):
     return keymap
 
 
+def km_node_link_modal_map(_params):
+    items = []
+    keymap = (
+        "Node Link Modal Map",
+        {"space_type": 'EMPTY', "region_type": 'WINDOW', "modal": True},
+        {"items": items},
+    )
+
+    items.extend([
+        ("BEGIN", {"type": 'LEFTMOUSE', "value": 'PRESS', "any": True}, None),
+        ("CONFIRM", {"type": 'LEFTMOUSE', "value": 'RELEASE', "any": True}, None),
+        ("CANCEL", {"type": 'RIGHTMOUSE', "value": 'PRESS', "any": True}, None),
+        ("CANCEL", {"type": 'ESC', "value": 'PRESS', "any": True}, None),
+        ("SWAP", {"type": 'LEFT_ALT', "value": 'ANY', "any": True}, None),
+        ("SWAP", {"type": 'RIGHT_ALT', "value": 'ANY', "any": True}, None),
+    ])
+
+    return keymap
+
 # Fallback for gizmos that don't have custom a custom key-map.
 def km_generic_gizmo(_params):
     keymap = (
@@ -8087,6 +8106,7 @@ def generate_keymaps(params=None):
         km_paint_stroke_modal(params),
         km_sculpt_expand_modal(params),
         km_curve_pen_modal_map(params),
+        km_node_link_modal_map(params),
 
         # Gizmos.
         km_generic_gizmo(params),

source/blender/editors/space_node/node_intern.hh

@@ -309,6 +309,8 @@ void NODE_OT_link_viewer(wmOperatorType *ot);
 
 void NODE_OT_insert_offset(wmOperatorType *ot);
 
+struct wmKeyMap *node_link_modal_keymap(struct wmKeyConfig *keyconf);
+
 /* node_edit.cc */
 
 float2 node_link_calculate_multi_input_position(const float2 &socket_position,

source/blender/editors/space_node/node_ops.cc

@@ -121,6 +121,8 @@ void node_keymap(wmKeyConfig *keyconf)
 
   /* Main Region only ----------------- */
   WM_keymap_ensure(keyconf, "Node Editor", SPACE_NODE, 0);
+
+  node_link_modal_keymap(keyconf);
 }
 
 }  // namespace blender::ed::space_node

source/blender/editors/space_node/node_relationships.cc

@@ -843,24 +843,6 @@ static void draw_draglink_tooltip_deactivate(const ARegion &region, bNodeLinkDra
   }
 }
 
-static void node_link_update_header(bContext *C, bNodeLinkDrag & /*nldrag*/)
-{
-  char header[UI_MAX_DRAW_STR];
-
-  const char *str_lmb = WM_key_event_string(LEFTMOUSE, true);
-  const char *str_rmb = WM_key_event_string(RIGHTMOUSE, true);
-  const char *str_alt = WM_key_event_string(EVT_LEFTALTKEY, true);
-
-  BLI_snprintf(header,
-               sizeof(header),
-               TIP_("%s: drag node link, %s: cancel, %s: swap node links"),
-               str_lmb,
-               str_rmb,
-               str_alt);
-
-  ED_workspace_status_text(C, header);
-}
-
 static int node_socket_count_links(const bNodeTree &ntree, const bNodeSocket &socket)
 {
   int count = 0;
@@ -1162,6 +1144,37 @@ static void node_link_find_socket(bContext &C, wmOperator &op, const float2 &cur
   }
 }
 
+enum class NodeLinkAction : int {
+  Begin,
+  Cancel,
+  Swap,
+  Confirm,
+};
+
+wmKeyMap *node_link_modal_keymap(wmKeyConfig *keyconf)
+{
+  static const EnumPropertyItem modal_items[] = {
+      {int(NodeLinkAction::Begin), "BEGIN", 0, "Drag Node-link", ""},
+      {int(NodeLinkAction::Confirm), "CONFIRM", 0, "Confirm Link", ""},
+      {int(NodeLinkAction::Cancel), "CANCEL", 0, "Cancel", ""},
+      {int(NodeLinkAction::Swap), "SWAP", 0, "Swap Links", ""},
+      {0, nullptr, 0, nullptr, nullptr},
+  };
+
+  wmKeyMap *keymap = WM_modalkeymap_find(keyconf, "Node Link Modal Map");
+
+  /* This function is called for each space-type, only needs to add map once. */
+  if (keymap && keymap->modal_items) {
+    return nullptr;
+  }
+
+  keymap = WM_modalkeymap_ensure(keyconf, "Node Link Modal Map", modal_items);
+
+  WM_modalkeymap_assign(keymap, "NODE_OT_link");
+
+  return keymap;
+}
+
 static int node_link_modal(bContext *C, wmOperator *op, const wmEvent *event)
 {
   bNodeLinkDrag &nldrag = *static_cast<bNodeLinkDrag *>(op->customdata);
@@ -1175,27 +1188,12 @@ static int node_link_modal(bContext *C, wmOperator *op, const wmEvent *event)
   nldrag.cursor[0] = event->mval[0];
   nldrag.cursor[1] = event->mval[1];
 
-  switch (event->type) {
-    case MOUSEMOVE:
-      if (nldrag.start_socket->is_multi_input() && nldrag.links.is_empty()) {
-        pick_input_link_by_link_intersect(*C, *op, nldrag, cursor);
+  if (event->type == EVT_MODAL_MAP) {
+    switch (event->val) {
+      case int(NodeLinkAction::Begin): {
+        return OPERATOR_RUNNING_MODAL;
       }
-      else {
-        node_link_find_socket(*C, *op, cursor);
-
-        node_link_update_header(C, nldrag);
-        ED_region_tag_redraw(region);
-      }
-
-      if (need_drag_link_tooltip(*snode.edittree, nldrag)) {
-        draw_draglink_tooltip_activate(*region, nldrag);
-      }
-      else {
-        draw_draglink_tooltip_deactivate(*region, nldrag);
-      }
-      break;
-    case LEFTMOUSE:
-      if (event->val == KM_RELEASE) {
+      case int(NodeLinkAction::Confirm): {
         /* Add a search menu for compatible sockets if the drag released on empty space. */
         if (should_create_drag_link_search_menu(*snode.edittree, nldrag)) {
           bNodeLink &link = nldrag.links.first();
@@ -1206,25 +1204,37 @@ static int node_link_modal(bContext *C, wmOperator *op, const wmEvent *event)
             invoke_node_link_drag_add_menu(*C, *link.tonode, *link.tosock, cursor);
           }
         }
-
         add_dragged_links_to_tree(*C, nldrag);
         return OPERATOR_FINISHED;
       }
-      break;
-    case RIGHTMOUSE:
-    case MIDDLEMOUSE: {
-      if (event->val == KM_RELEASE) {
+      case int(NodeLinkAction::Cancel): {
         node_link_cancel(C, op);
         return OPERATOR_CANCELLED;
       }
-      break;
+      case int(NodeLinkAction::Swap):
+        if (event->prev_val == KM_PRESS) {
+          nldrag.swap_links = true;
+        }
+        else if (event->prev_val == KM_RELEASE) {
+          nldrag.swap_links = false;
+        }
+        return OPERATOR_RUNNING_MODAL;
     }
-    case EVT_LEFTALTKEY:
-      nldrag.swap_links = (event->val == KM_PRESS);
-      break;
-    case EVT_ESCKEY: {
-      node_link_cancel(C, op);
-      return OPERATOR_CANCELLED;
+  }
+  else if (event->type == MOUSEMOVE) {
+    if (nldrag.start_socket->is_multi_input() && nldrag.links.is_empty()) {
+      pick_input_link_by_link_intersect(*C, *op, nldrag, cursor);
+    }
+    else {
+      node_link_find_socket(*C, *op, cursor);
+      ED_region_tag_redraw(region);
+    }
+
+    if (need_drag_link_tooltip(*snode.edittree, nldrag)) {
+      draw_draglink_tooltip_activate(*region, nldrag);
+    }
+    else {
+      draw_draglink_tooltip_deactivate(*region, nldrag);
     }
   }