1 files changed, 141 insertions, 0 deletions
diff --git a/source/blender/nodes/geometry/nodes/legacy/node_geo_attribute_color_ramp.cc b/source/blender/nodes/geometry/nodes/legacy/node_geo_attribute_color_ramp.cc
new file mode 100644
index 00000000000..aa054af3acd
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+++ b/source/blender/nodes/geometry/nodes/legacy/node_geo_attribute_color_ramp.cc
@@ -0,0 +1,141 @@
+/*
+ * 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 "BLI_task.hh"
+
+#include "BKE_colorband.h"
+
+#include "UI_interface.h"
+#include "UI_resources.h"
+
+#include "node_geometry_util.hh"
+
+namespace blender::nodes {
+
+static void geo_node_attribute_color_ramp_declare(NodeDeclarationBuilder &b)
+{
+  b.add_input<decl::Geometry>("Geometry");
+  b.add_input<decl::String>("Attribute");
+  b.add_input<decl::String>("Result");
+  b.add_output<decl::Geometry>("Geometry");
+}
+
+static void geo_node_attribute_color_ramp_layout(uiLayout *layout,
+                                                 bContext *UNUSED(C),
+                                                 PointerRNA *ptr)
+{
+  uiTemplateColorRamp(layout, ptr, "color_ramp", false);
+}
+
+static void geo_node_attribute_color_ramp_init(bNodeTree *UNUSED(ntree), bNode *node)
+{
+  NodeAttributeColorRamp *node_storage = (NodeAttributeColorRamp *)MEM_callocN(
+      sizeof(NodeAttributeColorRamp), __func__);
+  BKE_colorband_init(&node_storage->color_ramp, true);
+  node->storage = node_storage;
+}
+
+static AttributeDomain get_result_domain(const GeometryComponent &component,
+                                         StringRef input_name,
+                                         StringRef result_name)
+{
+  /* Use the domain of the result attribute if it already exists. */
+  std::optional<AttributeMetaData> result_info = component.attribute_get_meta_data(result_name);
+  if (result_info) {
+    return result_info->domain;
+  }
+
+  /* Otherwise use the input attribute's domain if it exists. */
+  std::optional<AttributeMetaData> source_info = component.attribute_get_meta_data(input_name);
+  if (source_info) {
+    return source_info->domain;
+  }
+
+  return ATTR_DOMAIN_POINT;
+}
+
+static void execute_on_component(const GeoNodeExecParams &params, GeometryComponent &component)
+{
+  const bNode &bnode = params.node();
+  NodeAttributeColorRamp *node_storage = (NodeAttributeColorRamp *)bnode.storage;
+  const std::string result_name = params.get_input<std::string>("Result");
+  const std::string input_name = params.get_input<std::string>("Attribute");
+
+  /* Always output a color attribute for now. We might want to allow users to customize.
+   * Using the type of an existing attribute could work, but does not have a real benefit
+   * currently. */
+  const AttributeDomain result_domain = get_result_domain(component, input_name, result_name);
+
+  OutputAttribute_Typed<ColorGeometry4f> attribute_result =
+      component.attribute_try_get_for_output_only<ColorGeometry4f>(result_name, result_domain);
+  if (!attribute_result) {
+    return;
+  }
+
+  GVArray_Typed<float> attribute_in = component.attribute_get_for_read<float>(
+      input_name, result_domain, 0.0f);
+
+  MutableSpan<ColorGeometry4f> results = attribute_result.as_span();
+
+  ColorBand *color_ramp = &node_storage->color_ramp;
+  threading::parallel_for(IndexRange(attribute_in.size()), 512, [&](IndexRange range) {
+    for (const int i : range) {
+      BKE_colorband_evaluate(color_ramp, attribute_in[i], results[i]);
+    }
+  });
+
+  attribute_result.save();
+}
+
+static void geo_node_attribute_color_ramp_exec(GeoNodeExecParams params)
+{
+  GeometrySet geometry_set = params.extract_input<GeometrySet>("Geometry");
+
+  geometry_set = geometry_set_realize_instances(geometry_set);
+
+  if (geometry_set.has<MeshComponent>()) {
+    execute_on_component(params, geometry_set.get_component_for_write<MeshComponent>());
+  }
+  if (geometry_set.has<PointCloudComponent>()) {
+    execute_on_component(params, geometry_set.get_component_for_write<PointCloudComponent>());
+  }
+  if (geometry_set.has<CurveComponent>()) {
+    execute_on_component(params, geometry_set.get_component_for_write<CurveComponent>());
+  }
+
+  params.set_output("Geometry", std::move(geometry_set));
+}
+
+}  // namespace blender::nodes
+
+void register_node_type_geo_attribute_color_ramp()
+{
+  static bNodeType ntype;
+
+  geo_node_type_base(&ntype,
+                     GEO_NODE_LEGACY_ATTRIBUTE_COLOR_RAMP,
+                     "Attribute Color Ramp",
+                     NODE_CLASS_ATTRIBUTE,
+                     0);
+  node_type_storage(
+      &ntype, "NodeAttributeColorRamp", node_free_standard_storage, node_copy_standard_storage);
+  node_type_init(&ntype, blender::nodes::geo_node_attribute_color_ramp_init);
+  node_type_size_preset(&ntype, NODE_SIZE_LARGE);
+  ntype.declare = blender::nodes::geo_node_attribute_color_ramp_declare;
+  ntype.geometry_node_execute = blender::nodes::geo_node_attribute_color_ramp_exec;
+  ntype.draw_buttons = blender::nodes::geo_node_attribute_color_ramp_layout;
+  nodeRegisterType(&ntype);
+}