Nodes: Add general Combine/Separate Color nodes

Inspired by D12936 and D12929, this patch adds general purpose
"Combine Color" and "Separate Color" nodes to Geometry, Compositor,
Shader and Texture nodes.
- Within Geometry Nodes, it replaces the existing "Combine RGB" and
  "Separate RGB" nodes.
- Within Compositor Nodes, it replaces the existing
  "Combine RGBA/HSVA/YCbCrA/YUVA" and "Separate RGBA/HSVA/YCbCrA/YUVA"
  nodes.
- Within Texture Nodes, it replaces the existing "Combine RGBA" and
  "Separate RGBA" nodes.
- Within Shader Nodes, it replaces the existing "Combine RGB/HSV" and
  "Separate RGB/HSV" nodes.

Python addons have not been updated to the new nodes yet.

**New shader code**
In node_color.h, color.h and gpu_shader_material_color_util.glsl,
missing methods hsl_to_rgb and rgb_to_hsl are added by directly
converting existing C code. They always produce the same result.

**Old code**
As requested by T96219, old nodes still exist but are not displayed in
the add menu. This means Python scripts can still create them as usual.
Otherwise, versioning replaces the old nodes with the new nodes when
opening .blend files.

Differential Revision: https://developer.blender.org/D14034

2 files changed, 141 insertions, 0 deletions

diff --git a/intern/cycles/scene/shader_nodes.cpp b/intern/cycles/scene/shader_nodes.cpp
index 95fccf725f3..06a2052d4cb 100644
--- a/intern/cycles/scene/shader_nodes.cpp
+++ b/intern/cycles/scene/shader_nodes.cpp
@@ -5010,6 +5010,63 @@ void MixNode::constant_fold(const ConstantFolder &folder)
   }
 }
 
+/* Combine Color */
+
+NODE_DEFINE(CombineColorNode)
+{
+  NodeType *type = NodeType::add("combine_color", create, NodeType::SHADER);
+
+  static NodeEnum type_enum;
+  type_enum.insert("rgb", NODE_COMBSEP_COLOR_RGB);
+  type_enum.insert("hsv", NODE_COMBSEP_COLOR_HSV);
+  type_enum.insert("hsl", NODE_COMBSEP_COLOR_HSL);
+  SOCKET_ENUM(color_type, "Type", type_enum, NODE_COMBSEP_COLOR_RGB);
+
+  SOCKET_IN_FLOAT(r, "Red", 0.0f);
+  SOCKET_IN_FLOAT(g, "Green", 0.0f);
+  SOCKET_IN_FLOAT(b, "Blue", 0.0f);
+
+  SOCKET_OUT_COLOR(color, "Color");
+
+  return type;
+}
+
+CombineColorNode::CombineColorNode() : ShaderNode(get_node_type())
+{
+}
+
+void CombineColorNode::constant_fold(const ConstantFolder &folder)
+{
+  if (folder.all_inputs_constant()) {
+    folder.make_constant(svm_combine_color(color_type, make_float3(r, g, b)));
+  }
+}
+
+void CombineColorNode::compile(SVMCompiler &compiler)
+{
+  ShaderInput *red_in = input("Red");
+  ShaderInput *green_in = input("Green");
+  ShaderInput *blue_in = input("Blue");
+  ShaderOutput *color_out = output("Color");
+
+  int red_stack_offset = compiler.stack_assign(red_in);
+  int green_stack_offset = compiler.stack_assign(green_in);
+  int blue_stack_offset = compiler.stack_assign(blue_in);
+  int color_stack_offset = compiler.stack_assign(color_out);
+
+  compiler.add_node(
+      NODE_COMBINE_COLOR,
+      color_type,
+      compiler.encode_uchar4(red_stack_offset, green_stack_offset, blue_stack_offset),
+      color_stack_offset);
+}
+
+void CombineColorNode::compile(OSLCompiler &compiler)
+{
+  compiler.parameter(this, "color_type");
+  compiler.add(this, "node_combine_color");
+}
+
 /* Combine RGB */
 
 NODE_DEFINE(CombineRGBNode)
@@ -5250,6 +5307,70 @@ void BrightContrastNode::compile(OSLCompiler &compiler)
   compiler.add(this, "node_brightness");
 }
 
+/* Separate Color */
+
+NODE_DEFINE(SeparateColorNode)
+{
+  NodeType *type = NodeType::add("separate_color", create, NodeType::SHADER);
+
+  static NodeEnum type_enum;
+  type_enum.insert("rgb", NODE_COMBSEP_COLOR_RGB);
+  type_enum.insert("hsv", NODE_COMBSEP_COLOR_HSV);
+  type_enum.insert("hsl", NODE_COMBSEP_COLOR_HSL);
+  SOCKET_ENUM(color_type, "Type", type_enum, NODE_COMBSEP_COLOR_RGB);
+
+  SOCKET_IN_COLOR(color, "Color", zero_float3());
+
+  SOCKET_OUT_FLOAT(r, "Red");
+  SOCKET_OUT_FLOAT(g, "Green");
+  SOCKET_OUT_FLOAT(b, "Blue");
+
+  return type;
+}
+
+SeparateColorNode::SeparateColorNode() : ShaderNode(get_node_type())
+{
+}
+
+void SeparateColorNode::constant_fold(const ConstantFolder &folder)
+{
+  if (folder.all_inputs_constant()) {
+    float3 col = svm_separate_color(color_type, color);
+
+    for (int channel = 0; channel < 3; channel++) {
+      if (outputs[channel] == folder.output) {
+        folder.make_constant(col[channel]);
+        return;
+      }
+    }
+  }
+}
+
+void SeparateColorNode::compile(SVMCompiler &compiler)
+{
+  ShaderInput *color_in = input("Color");
+  ShaderOutput *red_out = output("Red");
+  ShaderOutput *green_out = output("Green");
+  ShaderOutput *blue_out = output("Blue");
+
+  int color_stack_offset = compiler.stack_assign(color_in);
+  int red_stack_offset = compiler.stack_assign(red_out);
+  int green_stack_offset = compiler.stack_assign(green_out);
+  int blue_stack_offset = compiler.stack_assign(blue_out);
+
+  compiler.add_node(
+      NODE_SEPARATE_COLOR,
+      color_type,
+      color_stack_offset,
+      compiler.encode_uchar4(red_stack_offset, green_stack_offset, blue_stack_offset));
+}
+
+void SeparateColorNode::compile(OSLCompiler &compiler)
+{
+  compiler.parameter(this, "color_type");
+  compiler.add(this, "node_separate_color");
+}
+
 /* Separate RGB */
 
 NODE_DEFINE(SeparateRGBNode)
diff --git a/intern/cycles/scene/shader_nodes.h b/intern/cycles/scene/shader_nodes.h
index 9aef5d3151f..ac40a397c1e 100644
--- a/intern/cycles/scene/shader_nodes.h
+++ b/intern/cycles/scene/shader_nodes.h
@@ -1101,6 +1101,17 @@ class MixNode : public ShaderNode {
   NODE_SOCKET_API(float, fac)
 };
 
+class CombineColorNode : public ShaderNode {
+ public:
+  SHADER_NODE_CLASS(CombineColorNode)
+  void constant_fold(const ConstantFolder &folder);
+
+  NODE_SOCKET_API(NodeCombSepColorType, color_type)
+  NODE_SOCKET_API(float, r)
+  NODE_SOCKET_API(float, g)
+  NODE_SOCKET_API(float, b)
+};
+
 class CombineRGBNode : public ShaderNode {
  public:
   SHADER_NODE_CLASS(CombineRGBNode)
@@ -1150,6 +1161,15 @@ class BrightContrastNode : public ShaderNode {
   NODE_SOCKET_API(float, contrast)
 };
 
+class SeparateColorNode : public ShaderNode {
+ public:
+  SHADER_NODE_CLASS(SeparateColorNode)
+  void constant_fold(const ConstantFolder &folder);
+
+  NODE_SOCKET_API(NodeCombSepColorType, color_type)
+  NODE_SOCKET_API(float3, color)
+};
+
 class SeparateRGBNode : public ShaderNode {
  public:
   SHADER_NODE_CLASS(SeparateRGBNode)