1 files changed, 60 insertions, 0 deletions
diff --git a/source/blender/nodes/geometry/nodes/node_geo_input_index.cc b/source/blender/nodes/geometry/nodes/node_geo_input_index.cc
new file mode 100644
index 00000000000..c52ff3d448e
--- /dev/null
+++ b/source/blender/nodes/geometry/nodes/node_geo_input_index.cc
@@ -0,0 +1,60 @@
+/*
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version 2
+ * of the License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
+ */
+
+#include "node_geometry_util.hh"
+
+namespace blender::nodes {
+
+static void geo_node_input_index_declare(NodeDeclarationBuilder &b)
+{
+  b.add_output<decl::Int>("Index");
+}
+
+class IndexFieldInput final : public fn::FieldInput {
+ public:
+  IndexFieldInput() : FieldInput(CPPType::get<int>(), "Index")
+  {
+  }
+
+  const GVArray *get_varray_for_context(const fn::FieldContext &UNUSED(context),
+                                        IndexMask mask,
+                                        ResourceScope &scope) const final
+  {
+    /* TODO: Investigate a similar method to IndexRange::as_span() */
+    auto index_func = [](int i) { return i; };
+    return &scope.construct<
+        fn::GVArray_For_EmbeddedVArray<int, VArray_For_Func<int, decltype(index_func)>>>(
+        mask.min_array_size(), mask.min_array_size(), index_func);
+  }
+};
+
+static void geo_node_input_index_exec(GeoNodeExecParams params)
+{
+  Field<int> index_field{std::make_shared<IndexFieldInput>()};
+  params.set_output("Index", std::move(index_field));
+}
+
+}  // namespace blender::nodes
+
+void register_node_type_geo_input_index()
+{
+  static bNodeType ntype;
+
+  geo_node_type_base(&ntype, GEO_NODE_INPUT_INDEX, "Index", NODE_CLASS_INPUT, 0);
+  ntype.geometry_node_execute = blender::nodes::geo_node_input_index_exec;
+  ntype.declare = blender::nodes::geo_node_input_index_declare;
+  nodeRegisterType(&ntype);
+}