Geometry Nodes: Add Geometry Materials node

This adds a new `Geometry Materials` node that can get the list of materials from any geometry component that has them (i.e., Mesh, Point Cloud, Curve, Grease Pencil).

<img width="259" alt="image.png" src="attachments/f2742cdf-aef1-443c-a41e-0809c7430f0b">

This is a follow up to a PR that I closed about a half year ago (https://projects.blender.org/blender/blender/pulls/144628) now that lists are out of experimental!

Pull Request: https://projects.blender.org/blender/blender/pulls/161451

---------

Co-authored-by: Colin Basnett <5035660+cmbasnett@users.noreply.github.com>

scripts/startup/bl_ui/node_add_menu_geometry.py

@@ -458,6 +458,8 @@ class NODE_MT_gn_material_base(node_add_menu.NodeMenu):
 
     def draw(self, _context):
         layout = self.layout
+        self.node_operator(layout, "GeometryNodeGeometryMaterials")
+        layout.separator()
         self.node_operator(layout, "GeometryNodeReplaceMaterial")
         layout.separator()
         self.node_operator(layout, "GeometryNodeInputMaterialIndex")

source/blender/makesrna/intern/rna_nodetree.cc

@@ -11003,6 +11003,7 @@ static void rna_def_nodes(BlenderRNA *brna)
   define("GeometryNode", "GeometryNodeJoinGeometry");
   define("GeometryNode", "GeometryNodeListGetItem");
   define("GeometryNode", "GeometryNodeListLength");
+  define("GeometryNode", "GeometryNodeGeometryMaterials");
   define("GeometryNode", "GeometryNodeMaterialSelection");
   define("GeometryNode", "GeometryNodeMenuSwitch", def_geo_menu_switch);
   define("GeometryNode", "GeometryNodeMergeByDistance");

source/blender/nodes/geometry/CMakeLists.txt

@@ -98,6 +98,7 @@ set(SRC
   nodes/node_geo_filter_list.cc
   nodes/node_geo_flip_faces.cc
   nodes/node_geo_foreach_geometry_element.cc
+  nodes/node_geo_geometry_materials.cc
   nodes/node_geo_geometry_to_instance.cc
   nodes/node_geo_get_attribute_names.cc
   nodes/node_geo_get_bundle_item.cc

source/blender/nodes/geometry/nodes/node_geo_geometry_materials.cc

@@ -0,0 +1,106 @@
+/* SPDX-FileCopyrightText: 2026 Blender Authors
+ *
+ * SPDX-License-Identifier: GPL-2.0-or-later */
+
+#include "BKE_material.hh"
+
+#include "DNA_curves_types.h"
+#include "DNA_grease_pencil_types.h"
+#include "DNA_mesh_types.h"
+#include "DNA_object_types.h"
+#include "DNA_pointcloud_types.h"
+
+#include "NOD_geometry_nodes_list.hh"
+
+#include "RNA_enum_types.hh"
+
+#include "UI_interface_icons.hh"
+
+#include "node_geometry_util.hh"
+
+namespace blender::nodes::node_geo_geometry_materials {
+
+static void node_declare(NodeDeclarationBuilder &b)
+{
+  b.add_input<decl::Geometry>("Geometry"_ustr);
+  b.add_input<decl::Menu>("Component Type"_ustr)
+      .static_items(rna_enum_geometry_component_type_items,
+                    [](const EnumPropertyItem &item) {
+                      return ELEM(GeometryComponent::Type(item.value),
+                                  GeometryComponent::Type::Mesh,
+                                  GeometryComponent::Type::PointCloud,
+                                  GeometryComponent::Type::Curve,
+                                  GeometryComponent::Type::GreasePencil);
+                    })
+      .optional_label();
+  b.add_output<decl::Material>("Materials"_ustr).structure_type(StructureType::List);
+}
+
+static void node_geo_exec(GeoNodeExecParams params)
+{
+  const GeometrySet geometry_set = params.extract_input<GeometrySet>("Geometry"_ustr);
+  const GeometryComponent::Type component = params.extract_input<GeometryComponent::Type>(
+      "Component Type"_ustr);
+
+  Material **materials = nullptr;
+  int count = 0;
+
+  switch (component) {
+    case GeometryComponent::Type::Curve: {
+      if (const Curves *curves = geometry_set.get_curves()) {
+        materials = curves->mat;
+        count = curves->totcol;
+      }
+      break;
+    }
+    case GeometryComponent::Type::GreasePencil: {
+      if (const GreasePencil *grease_pencil = geometry_set.get_grease_pencil()) {
+        materials = grease_pencil->material_array;
+        count = grease_pencil->material_array_num;
+      }
+      break;
+    }
+    case GeometryComponent::Type::Mesh: {
+      if (const Mesh *mesh = geometry_set.get_mesh()) {
+        materials = mesh->mat;
+        count = mesh->totcol;
+      }
+      break;
+    }
+    case GeometryComponent::Type::PointCloud: {
+      if (const PointCloud *point_cloud = geometry_set.get_pointcloud()) {
+        materials = point_cloud->mat;
+        count = point_cloud->totcol;
+      }
+      break;
+    }
+    default:
+      break;
+  }
+
+  if (count == 0 || materials == nullptr) {
+    params.set_default_remaining_outputs();
+    return;
+  }
+
+  const CPPType &type = CPPType::get<Material *>();
+  GArray<> array(type, count, NoInitialization());
+  type.copy_construct_n(materials, array.data(), count);
+  params.set_output("Materials"_ustr, GList::from_garray(std::move(array)));
+}
+
+static void node_register()
+{
+  static bke::bNodeType ntype;
+
+  geo_node_type_base(&ntype, "GeometryNodeGeometryMaterials"_ustr);
+  ntype.ui_name = "Geometry Materials";
+  ntype.ui_description = "Get a list of the materials used by a geometry component";
+  ntype.nclass = NODE_CLASS_GEOMETRY;
+  ntype.geometry_node_execute = node_geo_exec;
+  ntype.declare = node_declare;
+  bke::node_register_type(ntype);
+}
+NOD_REGISTER_NODE(node_register)
+
+}  // namespace blender::nodes::node_geo_geometry_materials