Geometry Nodes: add Attribute Color Ramp node

Differential Revision: https://developer.blender.org/D9861

Ref T82585.

release/scripts/startup/nodeitems_builtins.py

@@ -485,6 +485,7 @@ geometry_node_categories = [
         NodeItem("GeometryNodeAttributeMath"),
         NodeItem("GeometryNodeAttributeFill"),
         NodeItem("GeometryNodeAttributeMix"),
+        NodeItem("GeometryNodeAttributeColorRamp"),
     ]),
     GeometryNodeCategory("GEO_COLOR", "Color", items=[
         NodeItem("ShaderNodeValToRGB"),

source/blender/blenkernel/BKE_node.h

@@ -1352,6 +1352,7 @@ int ntreeTexExecTree(struct bNodeTree *ntree,
 #define GEO_NODE_JOIN_GEOMETRY 1010
 #define GEO_NODE_ATTRIBUTE_FILL 1011
 #define GEO_NODE_ATTRIBUTE_MIX 1012
+#define GEO_NODE_ATTRIBUTE_COLOR_RAMP 1013
 
 /** \} */
 

source/blender/blenkernel/intern/node.c

@@ -4741,6 +4741,7 @@ static void registerGeometryNodes(void)
   register_node_type_geo_attribute_math();
   register_node_type_geo_join_geometry();
   register_node_type_geo_attribute_mix();
+  register_node_type_geo_attribute_color_ramp();
 }
 
 static void registerFunctionNodes(void)

source/blender/editors/space_node/drawnode.c

@@ -3215,6 +3215,13 @@ static void node_geometry_buts_attribute_point_distribute(uiLayout *layout,
   uiItemR(layout, ptr, "distribute_method", DEFAULT_FLAGS, "", ICON_NONE);
 }
 
+static void node_geometry_buts_attribute_color_ramp(uiLayout *layout,
+                                                    bContext *UNUSED(C),
+                                                    PointerRNA *ptr)
+{
+  uiTemplateColorRamp(layout, ptr, "color_ramp", 0);
+}
+
 static void node_geometry_set_butfunc(bNodeType *ntype)
 {
   switch (ntype->type) {
@@ -3245,6 +3252,9 @@ static void node_geometry_set_butfunc(bNodeType *ntype)
     case GEO_NODE_POINT_DISTRIBUTE:
       ntype->draw_buttons = node_geometry_buts_attribute_point_distribute;
       break;
+    case GEO_NODE_ATTRIBUTE_COLOR_RAMP:
+      ntype->draw_buttons = node_geometry_buts_attribute_color_ramp;
+      break;
   }
 }
 

source/blender/makesdna/DNA_node_types.h

@@ -1084,6 +1084,10 @@ typedef struct NodeAttributeMix {
   uint8_t input_type_b;
 } NodeAttributeMix;
 
+typedef struct NodeAttributeColorRamp {
+  ColorBand color_ramp;
+} NodeAttributeColorRamp;
+
 /* script node mode */
 #define NODE_SCRIPT_INTERNAL 0
 #define NODE_SCRIPT_EXTERNAL 1

source/blender/makesrna/intern/rna_nodetree.c

@@ -8507,6 +8507,18 @@ static void def_geo_point_distribute(StructRNA *srna)
   RNA_def_property_update(prop, NC_NODE | NA_EDITED, "rna_Node_socket_update");
 }
 
+static void def_geo_attribute_color_ramp(StructRNA *srna)
+{
+  PropertyRNA *prop;
+
+  RNA_def_struct_sdna_from(srna, "NodeAttributeColorRamp", "storage");
+
+  prop = RNA_def_property(srna, "color_ramp", PROP_POINTER, PROP_NONE);
+  RNA_def_property_struct_type(prop, "ColorRamp");
+  RNA_def_property_ui_text(prop, "Color Ramp", "");
+  RNA_def_property_update(prop, NC_NODE | NA_EDITED, "rna_Node_update");
+}
+
 /* -------------------------------------------------------------------------- */
 
 static void rna_def_shader_node(BlenderRNA *brna)

source/blender/nodes/CMakeLists.txt

@@ -138,6 +138,7 @@ set(SRC
   function/nodes/node_fn_switch.cc
   function/node_function_util.cc
 
+  geometry/nodes/node_geo_attribute_color_ramp.cc
   geometry/nodes/node_geo_attribute_fill.cc
   geometry/nodes/node_geo_attribute_math.cc
   geometry/nodes/node_geo_attribute_randomize.cc

source/blender/nodes/NOD_geometry.h

@@ -39,6 +39,7 @@ void register_node_type_geo_attribute_randomize(void);
 void register_node_type_geo_attribute_math(void);
 void register_node_type_geo_join_geometry(void);
 void register_node_type_geo_attribute_mix(void);
+void register_node_type_geo_attribute_color_ramp(void);
 
 #ifdef __cplusplus
 }

source/blender/nodes/NOD_static_types.h

@@ -279,6 +279,7 @@ DefNode(GeometryNode, GEO_NODE_ATTRIBUTE_MATH, def_geo_attribute_math, "ATTRIBUT
 DefNode(GeometryNode, GEO_NODE_JOIN_GEOMETRY, 0, "JOIN_GEOMETRY", JoinGeometry, "Join Geometry", "")
 DefNode(GeometryNode, GEO_NODE_ATTRIBUTE_FILL, def_geo_attribute_fill, "ATTRIBUTE_FILL", AttributeFill, "Attribute Fill", "")
 DefNode(GeometryNode, GEO_NODE_ATTRIBUTE_MIX, def_geo_attribute_mix, "ATTRIBUTE_MIX", AttributeMix, "Attribute Mix", "")
+DefNode(GeometryNode, GEO_NODE_ATTRIBUTE_COLOR_RAMP, def_geo_attribute_color_ramp, "ATTRIBUTE_COLOR_RAMP", AttributeColorRamp, "Attribute Color Ramp", "")
 
 /* undefine macros */
 #undef DefNode

source/blender/nodes/geometry/nodes/node_geo_attribute_color_ramp.cc

@@ -0,0 +1,107 @@
+/*
+ * 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"
+
+#include "BKE_colorband.h"
+
+static bNodeSocketTemplate geo_node_attribute_color_ramp_in[] = {
+    {SOCK_GEOMETRY, N_("Geometry")},
+    {SOCK_STRING, N_("Attribute")},
+    {SOCK_STRING, N_("Result")},
+    {-1, ""},
+};
+
+static bNodeSocketTemplate geo_node_attribute_color_ramp_out[] = {
+    {SOCK_GEOMETRY, N_("Geometry")},
+    {-1, ""},
+};
+
+namespace blender::nodes {
+
+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");
+  /* Once we support more domains at the user level, we have to decide how the result domain is
+   * choosen. */
+  const AttributeDomain result_domain = ATTR_DOMAIN_POINT;
+  const CustomDataType result_type = CD_PROP_COLOR;
+
+  WriteAttributePtr attribute_result = component.attribute_try_ensure_for_write(
+      result_name, result_domain, result_type);
+  if (!attribute_result) {
+    return;
+  }
+
+  Color4fWriteAttribute attribute_out = std::move(attribute_result);
+
+  const std::string input_name = params.get_input<std::string>("Attribute");
+  FloatReadAttribute attribute_in = component.attribute_get_for_read<float>(
+      input_name, result_domain, 0.0f);
+
+  Span<float> data_in = attribute_in.get_span();
+  MutableSpan<Color4f> data_out = attribute_out.get_span();
+
+  ColorBand *color_ramp = &node_storage->color_ramp;
+  for (const int i : data_in.index_range()) {
+    BKE_colorband_evaluate(color_ramp, data_in[i], data_out[i]);
+  }
+
+  attribute_out.apply_span();
+}
+
+static void geo_node_attribute_color_ramp_exec(GeoNodeExecParams params)
+{
+  GeometrySet geometry_set = params.extract_input<GeometrySet>("Geometry");
+
+  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>());
+  }
+
+  params.set_output("Geometry", std::move(geometry_set));
+}
+
+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;
+}
+
+}  // namespace blender::nodes
+
+void register_node_type_geo_attribute_color_ramp()
+{
+  static bNodeType ntype;
+
+  geo_node_type_base(
+      &ntype, GEO_NODE_ATTRIBUTE_COLOR_RAMP, "Attribute Color Ramp", NODE_CLASS_ATTRIBUTE, 0);
+  node_type_socket_templates(
+      &ntype, geo_node_attribute_color_ramp_in, geo_node_attribute_color_ramp_out);
+  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.geometry_node_execute = blender::nodes::geo_node_attribute_color_ramp_exec;
+  nodeRegisterType(&ntype);
+}