Geometry Nodes: support multiple group input nodes

Previously this was only supported within nested node groups.
Now it is also supported for the root node group that is referenced
by the modifier.

3 files changed, 20 insertions, 12 deletions

diff --git a/source/blender/blenkernel/BKE_geometry_set.hh b/source/blender/blenkernel/BKE_geometry_set.hh
index 8cc37a3e711..4454669b59a 100644
--- a/source/blender/blenkernel/BKE_geometry_set.hh
+++ b/source/blender/blenkernel/BKE_geometry_set.hh
@@ -313,6 +313,8 @@ struct GeometrySet {
   friend bool operator==(const GeometrySet &a, const GeometrySet &b);
   uint64_t hash() const;
 
+  void clear();
+
   /* Utility methods for creation. */
   static GeometrySet create_with_mesh(
       Mesh *mesh, GeometryOwnershipType ownership = GeometryOwnershipType::Owned);
diff --git a/source/blender/blenkernel/intern/geometry_set.cc b/source/blender/blenkernel/intern/geometry_set.cc
index a09c3f5f3d3..9f57fcfb2ba 100644
--- a/source/blender/blenkernel/intern/geometry_set.cc
+++ b/source/blender/blenkernel/intern/geometry_set.cc
@@ -205,6 +205,12 @@ uint64_t GeometrySet::hash() const
   return reinterpret_cast<uint64_t>(this);
 }
 
+/* Remove all geometry components from the geometry set. */
+void GeometrySet::clear()
+{
+  components_.clear();
+}
+
 /* Returns a read-only mesh or null. */
 const Mesh *GeometrySet::get_mesh_for_read() const
 {
diff --git a/source/blender/modifiers/intern/MOD_nodes.cc b/source/blender/modifiers/intern/MOD_nodes.cc
index d6f7b4c8561..8f9aa5c89ad 100644
--- a/source/blender/modifiers/intern/MOD_nodes.cc
+++ b/source/blender/modifiers/intern/MOD_nodes.cc
@@ -1057,7 +1057,7 @@ static void reset_tree_ui_storage(Span<const blender::nodes::NodeTreeRef *> tree
  * often than necessary. It's going to be replaced soon.
  */
 static GeometrySet compute_geometry(const DerivedNodeTree &tree,
-                                    Span<const OutputSocketRef *> group_input_sockets,
+                                    Span<const NodeRef *> group_input_nodes,
                                     const InputSocketRef &socket_to_compute,
                                     GeometrySet input_geometry_set,
                                     NodesModifierData *nmd,
@@ -1073,7 +1073,12 @@ static GeometrySet compute_geometry(const DerivedNodeTree &tree,
   Map<DOutputSocket, GMutablePointer> group_inputs;
 
   const DTreeContext *root_context = &tree.root_context();
-  if (group_input_sockets.size() > 0) {
+  for (const NodeRef *group_input_node : group_input_nodes) {
+    Span<const OutputSocketRef *> group_input_sockets = group_input_node->outputs().drop_back(1);
+    if (group_input_sockets.is_empty()) {
+      continue;
+    }
+
     Span<const OutputSocketRef *> remaining_input_sockets = group_input_sockets;
 
     /* If the group expects a geometry as first input, use the geometry that has been passed to
@@ -1081,7 +1086,7 @@ static GeometrySet compute_geometry(const DerivedNodeTree &tree,
     const OutputSocketRef *first_input_socket = group_input_sockets[0];
     if (first_input_socket->bsocket()->type == SOCK_GEOMETRY) {
       GeometrySet *geometry_set_in =
-          allocator.construct<GeometrySet>(std::move(input_geometry_set)).release();
+          allocator.construct<GeometrySet>(input_geometry_set).release();
       group_inputs.add_new({root_context, first_input_socket}, geometry_set_in);
       remaining_input_sockets = remaining_input_sockets.drop_front(1);
     }
@@ -1095,6 +1100,9 @@ static GeometrySet compute_geometry(const DerivedNodeTree &tree,
     }
   }
 
+  /* Don't keep a reference to the input geometry components to avoid copies during evaluation. */
+  input_geometry_set.clear();
+
   Vector<DInputSocket> group_outputs;
   group_outputs.append({root_context, &socket_to_compute});
 
@@ -1183,18 +1191,10 @@ static void modifyGeometry(ModifierData *md,
   Span<const NodeRef *> input_nodes = root_tree_ref.nodes_by_type("NodeGroupInput");
   Span<const NodeRef *> output_nodes = root_tree_ref.nodes_by_type("NodeGroupOutput");
 
-  if (input_nodes.size() > 1) {
-    return;
-  }
   if (output_nodes.size() != 1) {
     return;
   }
 
-  Span<const OutputSocketRef *> group_inputs;
-  if (input_nodes.size() == 1) {
-    group_inputs = input_nodes[0]->outputs().drop_back(1);
-  }
-
   Span<const InputSocketRef *> group_outputs = output_nodes[0]->inputs().drop_back(1);
 
   if (group_outputs.size() == 0) {
@@ -1211,7 +1211,7 @@ static void modifyGeometry(ModifierData *md,
   }
 
   geometry_set = compute_geometry(
-      tree, group_inputs, *group_outputs[0], std::move(geometry_set), nmd, ctx);
+      tree, input_nodes, *group_outputs[0], std::move(geometry_set), nmd, ctx);
 }
 
 static Mesh *modifyMesh(ModifierData *md, const ModifierEvalContext *ctx, Mesh *mesh)