Geometry Nodes: Set Curve Normal

This node allows for curves to have their evaluated normal mode changed
between MINIMUM_TWIST and Z_UP. A selection input allows for choosing
which spline in the curves object will be affected.

Differential Revision: D16118

2 files changed, 74 insertions, 0 deletions

diff --git a/source/blender/nodes/geometry/CMakeLists.txt b/source/blender/nodes/geometry/CMakeLists.txt
index a81bbec071b..d8391871571 100644
--- a/source/blender/nodes/geometry/CMakeLists.txt
+++ b/source/blender/nodes/geometry/CMakeLists.txt
@@ -148,6 +148,7 @@ set(SRC
   nodes/node_geo_separate_components.cc
   nodes/node_geo_separate_geometry.cc
   nodes/node_geo_set_curve_handles.cc
+  nodes/node_geo_set_curve_normal.cc
   nodes/node_geo_set_curve_radius.cc
   nodes/node_geo_set_curve_tilt.cc
   nodes/node_geo_set_id.cc
diff --git a/source/blender/nodes/geometry/nodes/node_geo_set_curve_normal.cc b/source/blender/nodes/geometry/nodes/node_geo_set_curve_normal.cc
new file mode 100644
index 00000000000..bac15622c2a
--- /dev/null
+++ b/source/blender/nodes/geometry/nodes/node_geo_set_curve_normal.cc
@@ -0,0 +1,73 @@
+/* SPDX-License-Identifier: GPL-2.0-or-later */
+
+#include "BKE_curves.hh"
+
+#include "UI_interface.h"
+#include "UI_resources.h"
+
+#include "node_geometry_util.hh"
+
+namespace blender::nodes::node_geo_set_curve_normal_cc {
+
+static void node_declare(NodeDeclarationBuilder &b)
+{
+  b.add_input<decl::Geometry>(N_("Curve")).supported_type(GEO_COMPONENT_TYPE_CURVE);
+  b.add_input<decl::Bool>(N_("Selection")).default_value(true).hide_value().supports_field();
+  b.add_output<decl::Geometry>(N_("Curve"));
+}
+
+static void node_layout(uiLayout *layout, bContext *UNUSED(C), PointerRNA *ptr)
+{
+  uiItemR(layout, ptr, "mode", 0, nullptr, ICON_NONE);
+}
+
+static void node_init(bNodeTree *UNUSED(tree), bNode *node)
+{
+  node->custom1 = NORMAL_MODE_MINIMUM_TWIST;
+}
+
+static void set_normal_mode(bke::CurvesGeometry &curves,
+                            const NormalMode mode,
+                            const Field<bool> &selection_field)
+{
+  bke::CurvesFieldContext field_context{curves, ATTR_DOMAIN_CURVE};
+  fn::FieldEvaluator evaluator{field_context, curves.curves_num()};
+  evaluator.set_selection(selection_field);
+  evaluator.evaluate();
+  const IndexMask selection = evaluator.get_evaluated_selection_as_mask();
+  curves.normal_mode_for_write().fill_indices(selection, mode);
+  curves.tag_normals_changed();
+}
+
+static void node_geo_exec(GeoNodeExecParams params)
+{
+  const NormalMode mode = static_cast<NormalMode>(params.node().custom1);
+
+  GeometrySet geometry_set = params.extract_input<GeometrySet>("Curve");
+  Field<bool> selection_field = params.extract_input<Field<bool>>("Selection");
+
+  geometry_set.modify_geometry_sets([&](GeometrySet &geometry_set) {
+    if (Curves *curves_id = geometry_set.get_curves_for_write()) {
+      bke::CurvesGeometry &curves = bke::CurvesGeometry::wrap(curves_id->geometry);
+      set_normal_mode(curves, mode, selection_field);
+    }
+  });
+
+  params.set_output("Curve", std::move(geometry_set));
+}
+
+}  // namespace blender::nodes::node_geo_set_curve_normal_cc
+
+void register_node_type_geo_set_curve_normal()
+{
+  namespace file_ns = blender::nodes::node_geo_set_curve_normal_cc;
+
+  static bNodeType ntype;
+  geo_node_type_base(&ntype, GEO_NODE_SET_CURVE_NORMAL, "Set Curve Normal", NODE_CLASS_GEOMETRY);
+  ntype.declare = file_ns::node_declare;
+  ntype.geometry_node_execute = file_ns::node_geo_exec;
+  node_type_init(&ntype, file_ns::node_init);
+  ntype.draw_buttons = file_ns::node_layout;
+
+  nodeRegisterType(&ntype);
+}