Geometry Nodes: Curve Primitive Bezier Segment

Creates a Curve with 1 Bezier Spline from four positions (start,
start handle, end handle, end) and a resolution. The handles are
aligned and mirrored automatically. An "Offset" mode is also included
to allow specifying the handles relative to the control points.

The default settings recreate the existing default Bezier Curve in the
3D viewport add menu.

Differential Revision: https://developer.blender.org/D11648

4 files changed, 152 insertions, 0 deletions

diff --git a/source/blender/nodes/CMakeLists.txt b/source/blender/nodes/CMakeLists.txt
index 2576756571c..926a81e87fd 100644
--- a/source/blender/nodes/CMakeLists.txt
+++ b/source/blender/nodes/CMakeLists.txt
@@ -164,6 +164,7 @@ set(SRC
   geometry/nodes/node_geo_common.cc
   geometry/nodes/node_geo_convex_hull.cc
   geometry/nodes/node_geo_curve_length.cc  
+  geometry/nodes/node_geo_curve_primitive_bezier_segment.cc
   geometry/nodes/node_geo_curve_primitive_quadratic_bezier.cc
   geometry/nodes/node_geo_curve_primitive_spiral.cc
   geometry/nodes/node_geo_curve_primitive_star.cc
diff --git a/source/blender/nodes/NOD_geometry.h b/source/blender/nodes/NOD_geometry.h
index b3797c1834c..ba646e7654a 100644
--- a/source/blender/nodes/NOD_geometry.h
+++ b/source/blender/nodes/NOD_geometry.h
@@ -52,6 +52,7 @@ void register_node_type_geo_bounding_box(void);
 void register_node_type_geo_collection_info(void);
 void register_node_type_geo_convex_hull(void);
 void register_node_type_geo_curve_length(void);
+void register_node_type_geo_curve_primitive_bezier_segment(void);
 void register_node_type_geo_curve_primitive_quadratic_bezier(void);
 void register_node_type_geo_curve_primitive_spiral(void);
 void register_node_type_geo_curve_primitive_star(void);
diff --git a/source/blender/nodes/NOD_static_types.h b/source/blender/nodes/NOD_static_types.h
index 5d2717b3bbd..19256f7383a 100644
--- a/source/blender/nodes/NOD_static_types.h
+++ b/source/blender/nodes/NOD_static_types.h
@@ -291,6 +291,7 @@ DefNode(GeometryNode, GEO_NODE_BOUNDING_BOX, 0, "BOUNDING_BOX", BoundBox, "Bound
 DefNode(GeometryNode, GEO_NODE_COLLECTION_INFO, def_geo_collection_info, "COLLECTION_INFO", CollectionInfo, "Collection Info", "")
 DefNode(GeometryNode, GEO_NODE_CONVEX_HULL, 0, "CONVEX_HULL", ConvexHull, "Convex Hull", "")
 DefNode(GeometryNode, GEO_NODE_CURVE_LENGTH, 0, "CURVE_LENGTH", CurveLength, "Curve Length", "")
+DefNode(GeometryNode, GEO_NODE_CURVE_PRIMITIVE_BEZIER_SEGMENT, def_geo_curve_primitive_bezier_segment, "CURVE_PRIMITIVE_BEZIER_SEGMENT", CurvePrimitiveBezierSegment, "Bezier Segment", "")
 DefNode(GeometryNode, GEO_NODE_CURVE_PRIMITIVE_QUADRATIC_BEZIER, 0, "CURVE_PRIMITIVE_QUADRATIC_BEZIER", CurveQuadraticBezier, "Quadratic Bezier", "")
 DefNode(GeometryNode, GEO_NODE_CURVE_PRIMITIVE_STAR, 0, "CURVE_PRIMITIVE_STAR", CurveStar, "Star", "")
 DefNode(GeometryNode, GEO_NODE_CURVE_PRIMITIVE_SPIRAL, 0, "CURVE_PRIMITIVE_SPIRAL", CurveSpiral, "Curve Spiral", "")
diff --git a/source/blender/nodes/geometry/nodes/node_geo_curve_primitive_bezier_segment.cc b/source/blender/nodes/geometry/nodes/node_geo_curve_primitive_bezier_segment.cc
new file mode 100644
index 00000000000..e167219ea6b
--- /dev/null
+++ b/source/blender/nodes/geometry/nodes/node_geo_curve_primitive_bezier_segment.cc
@@ -0,0 +1,149 @@
+/*
+ * 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 "BKE_spline.hh"
+
+#include "UI_interface.h"
+#include "UI_resources.h"
+
+#include "node_geometry_util.hh"
+
+static bNodeSocketTemplate geo_node_curve_primitive_bezier_segment_in[] = {
+    {SOCK_INT, N_("Resolution"), 16.0f, 0.0f, 0.0f, 0.0f, 1, 256, PROP_UNSIGNED},
+    {SOCK_VECTOR, N_("Start"), -1.0f, 0.0f, 0.0f, 0.0f, -FLT_MAX, FLT_MAX, PROP_TRANSLATION},
+    {SOCK_VECTOR,
+     N_("Start Handle"),
+     -0.5f,
+     0.5f,
+     0.0f,
+     0.0f,
+     -FLT_MAX,
+     FLT_MAX,
+     PROP_TRANSLATION},
+    {SOCK_VECTOR, N_("End Handle"), 0.0f, 0.0f, 0.0f, 0.0f, -FLT_MAX, FLT_MAX, PROP_TRANSLATION},
+    {SOCK_VECTOR, N_("End"), 1.0f, 0.0f, 0.0f, 0.0f, -FLT_MAX, FLT_MAX, PROP_TRANSLATION},
+    {-1, ""},
+};
+
+static bNodeSocketTemplate geo_node_curve_primitive_bezier_segment_out[] = {
+    {SOCK_GEOMETRY, N_("Curve")},
+    {-1, ""},
+};
+static void geo_node_curve_primitive_bezier_segment_layout(uiLayout *layout,
+                                                           bContext *UNUSED(C),
+                                                           PointerRNA *ptr)
+{
+  uiItemR(layout, ptr, "mode", UI_ITEM_R_EXPAND, nullptr, ICON_NONE);
+}
+
+namespace blender::nodes {
+
+static void geo_node_curve_primitive_bezier_segment_init(bNodeTree *UNUSED(tree), bNode *node)
+{
+  NodeGeometryCurvePrimitiveBezierSegment *data = (NodeGeometryCurvePrimitiveBezierSegment *)
+      MEM_callocN(sizeof(NodeGeometryCurvePrimitiveBezierSegment), __func__);
+
+  data->mode = GEO_NODE_CURVE_PRIMITIVE_BEZIER_SEGMENT_POSITION;
+  node->storage = data;
+}
+
+static std::unique_ptr<CurveEval> create_bezier_segment_curve(
+    const float3 start,
+    const float3 start_handle_right,
+    const float3 end,
+    const float3 end_handle_left,
+    const int resolution,
+    const GeometryNodeCurvePrimitiveBezierSegmentMode mode)
+{
+  std::unique_ptr<CurveEval> curve = std::make_unique<CurveEval>();
+  std::unique_ptr<BezierSpline> spline = std::make_unique<BezierSpline>();
+
+  if (mode == GEO_NODE_CURVE_PRIMITIVE_BEZIER_SEGMENT_POSITION) {
+    spline->add_point(start,
+                      BezierSpline::HandleType::Align,
+                      start - (start_handle_right - start) * -1.0f,
+                      BezierSpline::HandleType::Align,
+                      start_handle_right,
+                      1.0f,
+                      0.0f);
+    spline->add_point(end,
+                      BezierSpline::HandleType::Align,
+                      end_handle_left,
+                      BezierSpline::HandleType::Align,
+                      end - (end_handle_left - end) * -1.0f,
+                      1.0f,
+                      0.0f);
+  }
+  else {
+    spline->add_point(start,
+                      BezierSpline::HandleType::Align,
+                      start - start_handle_right,
+                      BezierSpline::HandleType::Align,
+                      start + start_handle_right,
+                      1.0f,
+                      0.0f);
+    spline->add_point(end,
+                      BezierSpline::HandleType::Align,
+                      end + end_handle_left,
+                      BezierSpline::HandleType::Align,
+                      end - end_handle_left,
+                      1.0f,
+                      0.0f);
+  }
+
+  spline->set_resolution(resolution);
+  spline->attributes.reallocate(spline->size());
+  curve->add_spline(std::move(spline));
+  curve->attributes.reallocate(curve->splines().size());
+  return curve;
+}
+
+static void geo_node_curve_primitive_bezier_segment_exec(GeoNodeExecParams params)
+{
+  const NodeGeometryCurvePrimitiveBezierSegment *node_storage =
+      (NodeGeometryCurvePrimitiveBezierSegment *)params.node().storage;
+  const GeometryNodeCurvePrimitiveBezierSegmentMode mode =
+      (const GeometryNodeCurvePrimitiveBezierSegmentMode)node_storage->mode;
+
+  std::unique_ptr<CurveEval> curve = create_bezier_segment_curve(
+      params.extract_input<float3>("Start"),
+      params.extract_input<float3>("Start Handle"),
+      params.extract_input<float3>("End"),
+      params.extract_input<float3>("End Handle"),
+      std::max(params.extract_input<int>("Resolution"), 1),
+      mode);
+  params.set_output("Curve", GeometrySet::create_with_curve(curve.release()));
+}
+
+}  // namespace blender::nodes
+
+void register_node_type_geo_curve_primitive_bezier_segment()
+{
+  static bNodeType ntype;
+  geo_node_type_base(
+      &ntype, GEO_NODE_CURVE_PRIMITIVE_BEZIER_SEGMENT, "Bezier Segment", NODE_CLASS_GEOMETRY, 0);
+  node_type_socket_templates(&ntype,
+                             geo_node_curve_primitive_bezier_segment_in,
+                             geo_node_curve_primitive_bezier_segment_out);
+  node_type_init(&ntype, blender::nodes::geo_node_curve_primitive_bezier_segment_init);
+  node_type_storage(&ntype,
+                    "NodeGeometryCurvePrimitiveBezierSegment",
+                    node_free_standard_storage,
+                    node_copy_standard_storage);
+  ntype.draw_buttons = geo_node_curve_primitive_bezier_segment_layout;
+  ntype.geometry_node_execute = blender::nodes::geo_node_curve_primitive_bezier_segment_exec;
+  nodeRegisterType(&ntype);
+}