Nodes: move NodeTreeRef functionality into node runtime data

The purpose of `NodeTreeRef` was to speed up various queries on a read-only
`bNodeTree`. Not that we have runtime data in nodes and sockets, we can also
store the result of some queries there. This has some benefits:
* No need for a read-only separate node tree data structure which increased
  complexity.
* Makes it easier to reuse cached queries in more parts of Blender that can
  benefit from it.

A downside is that we loose some type safety that we got by having different
types for input and output sockets, as well as internal and non-internal links.

This patch also refactors `DerivedNodeTree` so that it does not use
`NodeTreeRef` anymore, but uses `bNodeTree` directly instead.

To provide a convenient API (that is also close to what `NodeTreeRef` has), a
new approach is implemented: `bNodeTree`, `bNode`, `bNodeSocket` and `bNodeLink`
now have C++ methods declared in `DNA_node_types.h` which are implemented in
`BKE_node_runtime.hh`. To make this work, `makesdna` now skips c++ sections when
parsing dna header files.

No user visible changes are expected.

Differential Revision: https://developer.blender.org/D15491

12 files changed, 13 insertions, 11 deletions

diff --git a/source/blender/nodes/function/node_function_util.hh b/source/blender/nodes/function/node_function_util.hh
index fd0b6c31b1d..059b2f9bc17 100644
--- a/source/blender/nodes/function/node_function_util.hh
+++ b/source/blender/nodes/function/node_function_util.hh
@@ -23,4 +23,6 @@
 
 #include "FN_multi_function_builder.hh"
 
+#include "RNA_access.h"
+
 void fn_node_type_base(struct bNodeType *ntype, int type, const char *name, short nclass);
diff --git a/source/blender/nodes/function/nodes/node_fn_align_euler_to_vector.cc b/source/blender/nodes/function/nodes/node_fn_align_euler_to_vector.cc
index 7d08d57c503..e5c89567d44 100644
--- a/source/blender/nodes/function/nodes/node_fn_align_euler_to_vector.cc
+++ b/source/blender/nodes/function/nodes/node_fn_align_euler_to_vector.cc
@@ -190,7 +190,7 @@ class MF_AlignEulerToVector : public fn::MultiFunction {
 
 static void fn_node_align_euler_to_vector_build_multi_function(NodeMultiFunctionBuilder &builder)
 {
-  bNode &node = builder.node();
+  const bNode &node = builder.node();
   builder.construct_and_set_matching_fn<MF_AlignEulerToVector>(node.custom1, node.custom2);
 }
 
diff --git a/source/blender/nodes/function/nodes/node_fn_boolean_math.cc b/source/blender/nodes/function/nodes/node_fn_boolean_math.cc
index b6d7e6c9a5f..5fc28509a49 100644
--- a/source/blender/nodes/function/nodes/node_fn_boolean_math.cc
+++ b/source/blender/nodes/function/nodes/node_fn_boolean_math.cc
@@ -68,7 +68,7 @@ static void node_gather_link_searches(GatherLinkSearchOpParams &params)
   }
 }
 
-static const fn::MultiFunction *get_multi_function(bNode &bnode)
+static const fn::MultiFunction *get_multi_function(const bNode &bnode)
 {
   static auto exec_preset = fn::CustomMF_presets::AllSpanOrSingle();
   static fn::CustomMF_SI_SI_SO<bool, bool, bool> and_fn{
diff --git a/source/blender/nodes/function/nodes/node_fn_combine_color.cc b/source/blender/nodes/function/nodes/node_fn_combine_color.cc
index c5fd3ce38a1..450cd166e78 100644
--- a/source/blender/nodes/function/nodes/node_fn_combine_color.cc
+++ b/source/blender/nodes/function/nodes/node_fn_combine_color.cc
@@ -49,7 +49,7 @@ static void fn_node_combine_color_init(bNodeTree *UNUSED(tree), bNode *node)
   node->storage = data;
 }
 
-static const fn::MultiFunction *get_multi_function(bNode &bnode)
+static const fn::MultiFunction *get_multi_function(const bNode &bnode)
 {
   const NodeCombSepColor &storage = node_storage(bnode);
 
diff --git a/source/blender/nodes/function/nodes/node_fn_compare.cc b/source/blender/nodes/function/nodes/node_fn_compare.cc
index e3f13dc7d6b..122d1a3c93e 100644
--- a/source/blender/nodes/function/nodes/node_fn_compare.cc
+++ b/source/blender/nodes/function/nodes/node_fn_compare.cc
@@ -167,7 +167,7 @@ static float component_average(float3 a)
   return (a.x + a.y + a.z) / 3.0f;
 }
 
-static const fn::MultiFunction *get_multi_function(bNode &node)
+static const fn::MultiFunction *get_multi_function(const bNode &node)
 {
   const NodeFunctionCompare *data = (NodeFunctionCompare *)node.storage;
 
diff --git a/source/blender/nodes/function/nodes/node_fn_float_to_int.cc b/source/blender/nodes/function/nodes/node_fn_float_to_int.cc
index 9c9d8620a7e..aad2f532d20 100644
--- a/source/blender/nodes/function/nodes/node_fn_float_to_int.cc
+++ b/source/blender/nodes/function/nodes/node_fn_float_to_int.cc
@@ -39,7 +39,7 @@ static void node_float_to_int_label(const bNodeTree *UNUSED(ntree),
   BLI_strncpy(label, IFACE_(name), maxlen);
 }
 
-static const fn::MultiFunction *get_multi_function(bNode &bnode)
+static const fn::MultiFunction *get_multi_function(const bNode &bnode)
 {
   static auto exec_preset = fn::CustomMF_presets::AllSpanOrSingle();
   static fn::CustomMF_SI_SO<float, int> round_fn{
diff --git a/source/blender/nodes/function/nodes/node_fn_input_bool.cc b/source/blender/nodes/function/nodes/node_fn_input_bool.cc
index 5ced719627f..717f4d1ac6b 100644
--- a/source/blender/nodes/function/nodes/node_fn_input_bool.cc
+++ b/source/blender/nodes/function/nodes/node_fn_input_bool.cc
@@ -22,7 +22,7 @@ static void fn_node_input_bool_layout(uiLayout *layout, bContext *UNUSED(C), Poi
 
 static void fn_node_input_bool_build_multi_function(NodeMultiFunctionBuilder &builder)
 {
-  bNode &bnode = builder.node();
+  const bNode &bnode = builder.node();
   NodeInputBool *node_storage = static_cast<NodeInputBool *>(bnode.storage);
   builder.construct_and_set_matching_fn<fn::CustomMF_Constant<bool>>(node_storage->boolean);
 }
diff --git a/source/blender/nodes/function/nodes/node_fn_input_color.cc b/source/blender/nodes/function/nodes/node_fn_input_color.cc
index 46787f7575d..cdad1542c66 100644
--- a/source/blender/nodes/function/nodes/node_fn_input_color.cc
+++ b/source/blender/nodes/function/nodes/node_fn_input_color.cc
@@ -23,7 +23,7 @@ static void fn_node_input_color_layout(uiLayout *layout, bContext *UNUSED(C), Po
 static void fn_node_input_color_build_multi_function(
     blender::nodes::NodeMultiFunctionBuilder &builder)
 {
-  bNode &bnode = builder.node();
+  const bNode &bnode = builder.node();
   NodeInputColor *node_storage = static_cast<NodeInputColor *>(bnode.storage);
   blender::ColorGeometry4f color = (ColorGeometry4f)node_storage->color;
   builder.construct_and_set_matching_fn<blender::fn::CustomMF_Constant<ColorGeometry4f>>(color);
diff --git a/source/blender/nodes/function/nodes/node_fn_input_int.cc b/source/blender/nodes/function/nodes/node_fn_input_int.cc
index 1e5dcd5ae7a..16506b5f9b8 100644
--- a/source/blender/nodes/function/nodes/node_fn_input_int.cc
+++ b/source/blender/nodes/function/nodes/node_fn_input_int.cc
@@ -22,7 +22,7 @@ static void fn_node_input_int_layout(uiLayout *layout, bContext *UNUSED(C), Poin
 
 static void fn_node_input_int_build_multi_function(NodeMultiFunctionBuilder &builder)
 {
-  bNode &bnode = builder.node();
+  const bNode &bnode = builder.node();
   NodeInputInt *node_storage = static_cast<NodeInputInt *>(bnode.storage);
   builder.construct_and_set_matching_fn<fn::CustomMF_Constant<int>>(node_storage->integer);
 }
diff --git a/source/blender/nodes/function/nodes/node_fn_input_string.cc b/source/blender/nodes/function/nodes/node_fn_input_string.cc
index 124a8572f78..129d19f4f04 100644
--- a/source/blender/nodes/function/nodes/node_fn_input_string.cc
+++ b/source/blender/nodes/function/nodes/node_fn_input_string.cc
@@ -20,7 +20,7 @@ static void fn_node_input_string_layout(uiLayout *layout, bContext *UNUSED(C), P
 
 static void fn_node_input_string_build_multi_function(NodeMultiFunctionBuilder &builder)
 {
-  bNode &bnode = builder.node();
+  const bNode &bnode = builder.node();
   NodeInputString *node_storage = static_cast<NodeInputString *>(bnode.storage);
   std::string string = std::string((node_storage->string) ? node_storage->string : "");
   builder.construct_and_set_matching_fn<fn::CustomMF_Constant<std::string>>(std::move(string));
diff --git a/source/blender/nodes/function/nodes/node_fn_input_vector.cc b/source/blender/nodes/function/nodes/node_fn_input_vector.cc
index 898c19e92f0..de894a4038d 100644
--- a/source/blender/nodes/function/nodes/node_fn_input_vector.cc
+++ b/source/blender/nodes/function/nodes/node_fn_input_vector.cc
@@ -22,7 +22,7 @@ static void fn_node_input_vector_layout(uiLayout *layout, bContext *UNUSED(C), P
 
 static void fn_node_input_vector_build_multi_function(NodeMultiFunctionBuilder &builder)
 {
-  bNode &bnode = builder.node();
+  const bNode &bnode = builder.node();
   NodeInputVector *node_storage = static_cast<NodeInputVector *>(bnode.storage);
   float3 vector(node_storage->vector);
   builder.construct_and_set_matching_fn<fn::CustomMF_Constant<float3>>(vector);
diff --git a/source/blender/nodes/function/nodes/node_fn_rotate_euler.cc b/source/blender/nodes/function/nodes/node_fn_rotate_euler.cc
index a4fc1a6bfd1..299c0f7a932 100644
--- a/source/blender/nodes/function/nodes/node_fn_rotate_euler.cc
+++ b/source/blender/nodes/function/nodes/node_fn_rotate_euler.cc
@@ -52,7 +52,7 @@ static void fn_node_rotate_euler_layout(uiLayout *layout, bContext *UNUSED(C), P
   uiItemR(layout, ptr, "space", UI_ITEM_R_EXPAND, nullptr, ICON_NONE);
 }
 
-static const fn::MultiFunction *get_multi_function(bNode &bnode)
+static const fn::MultiFunction *get_multi_function(const bNode &bnode)
 {
   static fn::CustomMF_SI_SI_SO<float3, float3, float3> obj_euler_rot{
       "Rotate Euler by Euler/Object", [](const float3 &input, const float3 &rotation) {