Add simulation node tree type

This implements a new builtin node tree type called `SimulationNodeTree`.
It is not yet embedded in the `Simulation` data block.

This is part of T73324.

The `WITH_NEW_SIMULATION_TYPE` cmake option is used to control whether `Simulation Editor` is shown in the editors menu.
Disabling the rna code with this option was a bit tricky, because the node tree type stores a reference to the rna type.
I could do the `#ifdef WITH_NEW_SIMULATION_TYPE` everywhere, but I'm not sure if it is worth the effort.

Currently there is only the group node, which is unusable, because there are no other nodes.
I'll submit those for review separately.

Differential Revision: https://developer.blender.org/D7287

19 files changed, 249 insertions, 4 deletions

diff --git a/source/blender/blenkernel/intern/node.c b/source/blender/blenkernel/intern/node.c
index 06ddf4a8582..cc04d235783 100644
--- a/source/blender/blenkernel/intern/node.c
+++ b/source/blender/blenkernel/intern/node.c
@@ -66,6 +66,7 @@
 #include "NOD_common.h"
 #include "NOD_composite.h"
 #include "NOD_shader.h"
+#include "NOD_simulation.h"
 #include "NOD_socket.h"
 #include "NOD_texture.h"
 
@@ -4113,6 +4114,11 @@ static void registerTextureNodes(void)
   register_node_type_tex_proc_distnoise();
 }
 
+static void registerSimulationNodes(void)
+{
+  register_node_type_sim_group();
+}
+
 void init_nodesystem(void)
 {
   nodetreetypes_hash = BLI_ghash_str_new("nodetreetypes_hash gh");
@@ -4126,6 +4132,7 @@ void init_nodesystem(void)
   register_node_tree_type_cmp();
   register_node_tree_type_sh();
   register_node_tree_type_tex();
+  register_node_tree_type_sim();
 
   register_node_type_frame();
   register_node_type_reroute();
@@ -4135,6 +4142,7 @@ void init_nodesystem(void)
   registerCompositNodes();
   registerShaderNodes();
   registerTextureNodes();
+  registerSimulationNodes();
 }
 
 void free_nodesystem(void)
diff --git a/source/blender/editors/include/ED_node.h b/source/blender/editors/include/ED_node.h
index ae2b4989069..d7db99d4f6c 100644
--- a/source/blender/editors/include/ED_node.h
+++ b/source/blender/editors/include/ED_node.h
@@ -94,6 +94,7 @@ void ED_node_set_tree_type(struct SpaceNode *snode, struct bNodeTreeType *typein
 bool ED_node_is_compositor(struct SpaceNode *snode);
 bool ED_node_is_shader(struct SpaceNode *snode);
 bool ED_node_is_texture(struct SpaceNode *snode);
+bool ED_node_is_simulation(struct SpaceNode *snode);
 
 void ED_node_shader_default(const struct bContext *C, struct ID *id);
 void ED_node_composit_default(const struct bContext *C, struct Scene *scene);
diff --git a/source/blender/editors/space_node/CMakeLists.txt b/source/blender/editors/space_node/CMakeLists.txt
index f8c30f9a688..4e21cdc9d16 100644
--- a/source/blender/editors/space_node/CMakeLists.txt
+++ b/source/blender/editors/space_node/CMakeLists.txt
@@ -75,6 +75,10 @@ if(WITH_OPENIMAGEDENOISE)
   add_definitions(-DWITH_OPENIMAGEDENOISE)
 endif()
 
+if (WITH_NEW_SIMULATION_TYPE)
+  add_definitions(-DWITH_NEW_SIMULATION_TYPE)
+endif()
+
 add_definitions(${GL_DEFINITIONS})
 
 blender_add_lib(bf_editor_space_node "${SRC}" "${INC}" "${INC_SYS}" "${LIB}")
diff --git a/source/blender/editors/space_node/drawnode.c b/source/blender/editors/space_node/drawnode.c
index 55a5a043014..e1450efba6d 100644
--- a/source/blender/editors/space_node/drawnode.c
+++ b/source/blender/editors/space_node/drawnode.c
@@ -69,6 +69,7 @@
 
 #include "NOD_composite.h"
 #include "NOD_shader.h"
+#include "NOD_simulation.h"
 #include "NOD_texture.h"
 #include "node_intern.h" /* own include */
 
@@ -3122,6 +3123,12 @@ static void node_texture_set_butfunc(bNodeType *ntype)
   }
 }
 
+/* ****************** BUTTON CALLBACKS FOR SIMULATION NODES ***************** */
+
+static void node_simulation_set_butfunc(bNodeType *UNUSED(ntype))
+{
+}
+
 /* ****** init draw callbacks for all tree types, only called in usiblender.c, once ************ */
 
 static void node_property_update_default(Main *bmain, Scene *UNUSED(scene), PointerRNA *ptr)
@@ -3230,6 +3237,7 @@ void ED_node_init_butfuncs(void)
     node_composit_set_butfunc(ntype);
     node_shader_set_butfunc(ntype);
     node_texture_set_butfunc(ntype);
+    node_simulation_set_butfunc(ntype);
 
     /* define update callbacks for socket properties */
     node_template_properties_update(ntype);
@@ -3240,6 +3248,7 @@ void ED_node_init_butfuncs(void)
   ntreeType_Composite->ui_icon = ICON_NODE_COMPOSITING;
   ntreeType_Shader->ui_icon = ICON_NODE_MATERIAL;
   ntreeType_Texture->ui_icon = ICON_NODE_TEXTURE;
+  ntreeType_Simulation->ui_icon = ICON_PHYSICS; /* TODO: Use correct icon. */
 }
 
 void ED_init_custom_node_type(bNodeType *ntype)
diff --git a/source/blender/editors/space_node/node_edit.c b/source/blender/editors/space_node/node_edit.c
index e50f5a818aa..6c7770aa531 100644
--- a/source/blender/editors/space_node/node_edit.c
+++ b/source/blender/editors/space_node/node_edit.c
@@ -69,6 +69,7 @@
 
 #include "NOD_composite.h"
 #include "NOD_shader.h"
+#include "NOD_simulation.h"
 #include "NOD_texture.h"
 #include "node_intern.h" /* own include */
 
@@ -438,6 +439,11 @@ bool ED_node_is_texture(struct SpaceNode *snode)
   return STREQ(snode->tree_idname, ntreeType_Texture->idname);
 }
 
+bool ED_node_is_simulation(struct SpaceNode *snode)
+{
+  return STREQ(snode->tree_idname, ntreeType_Simulation->idname);
+}
+
 /* assumes nothing being done in ntree yet, sets the default in/out node */
 /* called from shading buttons or header */
 void ED_node_shader_default(const bContext *C, ID *id)
diff --git a/source/blender/editors/space_node/node_group.c b/source/blender/editors/space_node/node_group.c
index 2a4c6147d5d..0f296fd293a 100644
--- a/source/blender/editors/space_node/node_group.c
+++ b/source/blender/editors/space_node/node_group.c
@@ -69,7 +69,8 @@ static bool node_group_operator_active(bContext *C)
      */
     if (STREQ(snode->tree_idname, "ShaderNodeTree") ||
         STREQ(snode->tree_idname, "CompositorNodeTree") ||
-        STREQ(snode->tree_idname, "TextureNodeTree")) {
+        STREQ(snode->tree_idname, "TextureNodeTree") ||
+        STREQ(snode->tree_idname, "SimulationNodeTree")) {
       return true;
     }
   }
@@ -85,7 +86,8 @@ static bool node_group_operator_editable(bContext *C)
      * Disabled otherwise to allow pynodes define their own operators
      * with same keymap.
      */
-    if (ED_node_is_shader(snode) || ED_node_is_compositor(snode) || ED_node_is_texture(snode)) {
+    if (ED_node_is_shader(snode) || ED_node_is_compositor(snode) || ED_node_is_texture(snode) ||
+        ED_node_is_simulation(snode)) {
       return true;
     }
   }
@@ -111,6 +113,9 @@ static const char *group_node_idname(bContext *C)
   else if (ED_node_is_texture(snode)) {
     return "TextureNodeGroup";
   }
+  else if (ED_node_is_simulation(snode)) {
+    return "SimulationNodeGroup";
+  }
 
   return "";
 }
diff --git a/source/blender/editors/space_node/space_node.c b/source/blender/editors/space_node/space_node.c
index 32007d5b971..a86818b577b 100644
--- a/source/blender/editors/space_node/space_node.c
+++ b/source/blender/editors/space_node/space_node.c
@@ -939,6 +939,11 @@ static void node_space_subtype_item_extend(bContext *C, EnumPropertyItem **item,
   bool free;
   const EnumPropertyItem *item_src = RNA_enum_node_tree_types_itemf_impl(C, &free);
   for (const EnumPropertyItem *item_iter = item_src; item_iter->identifier; item_iter++) {
+#ifndef WITH_NEW_SIMULATION_TYPE
+    if (STREQ(item_iter->identifier, "SimulationNodeTree")) {
+      continue;
+    }
+#endif
     RNA_enum_item_add(item, totitem, item_iter);
   }
   if (free) {
diff --git a/source/blender/makesdna/DNA_node_types.h b/source/blender/makesdna/DNA_node_types.h
index 8029e8ebc13..069449fcba7 100644
--- a/source/blender/makesdna/DNA_node_types.h
+++ b/source/blender/makesdna/DNA_node_types.h
@@ -498,6 +498,7 @@ typedef struct bNodeTree {
 #define NTREE_SHADER 0
 #define NTREE_COMPOSIT 1
 #define NTREE_TEXTURE 2
+#define NTREE_SIMULATION 3
 
 /* ntree->init, flag */
 #define NTREE_TYPE_INIT 1
diff --git a/source/blender/makesrna/RNA_access.h b/source/blender/makesrna/RNA_access.h
index 087b4c35c02..229411829f5 100644
--- a/source/blender/makesrna/RNA_access.h
+++ b/source/blender/makesrna/RNA_access.h
@@ -549,6 +549,8 @@ extern StructRNA RNA_ShrinkwrapModifier;
 extern StructRNA RNA_SimpleDeformModifier;
 extern StructRNA RNA_SimplifyGpencilModifier;
 extern StructRNA RNA_Simulation;
+extern StructRNA RNA_SimulationNode;
+extern StructRNA RNA_SimulationNodeTree;
 extern StructRNA RNA_SkinModifier;
 extern StructRNA RNA_SmoothGpencilModifier;
 extern StructRNA RNA_SmoothModifier;
diff --git a/source/blender/makesrna/intern/rna_nodetree.c b/source/blender/makesrna/intern/rna_nodetree.c
index 29c36b21b7f..4fc20a44dbb 100644
--- a/source/blender/makesrna/intern/rna_nodetree.c
+++ b/source/blender/makesrna/intern/rna_nodetree.c
@@ -669,6 +669,20 @@ static const EnumPropertyItem *rna_node_static_type_itemf(bContext *UNUSED(C),
 #  undef DefNode
   }
 
+  if (RNA_struct_is_a(ptr->type, &RNA_SimulationNode)) {
+#  define DefNode(Category, ID, DefFunc, EnumName, StructName, UIName, UIDesc) \
+    if (STREQ(#Category, "SimulationNode")) { \
+      tmp.value = ID; \
+      tmp.identifier = EnumName; \
+      tmp.name = UIName; \
+      tmp.description = UIDesc; \
+      tmp.icon = ICON_NONE; \
+      RNA_enum_item_add(&item, &totitem, &tmp); \
+    }
+#  include "../../nodes/NOD_static_types.h"
+#  undef DefNode
+  }
+
   RNA_enum_item_end(&item, &totitem);
   *r_free = true;
 
@@ -1785,6 +1799,28 @@ static StructRNA *rna_TextureNode_register(Main *bmain,
   return nt->ext.srna;
 }
 
+static StructRNA *rna_SimulationNode_register(Main *bmain,
+                                              ReportList *reports,
+                                              void *data,
+                                              const char *identifier,
+                                              StructValidateFunc validate,
+                                              StructCallbackFunc call,
+                                              StructFreeFunc free)
+{
+  bNodeType *nt = rna_Node_register_base(
+      bmain, reports, &RNA_SimulationNode, data, identifier, validate, call, free);
+  if (!nt) {
+    return NULL;
+  }
+
+  nodeRegisterType(nt);
+
+  /* update while blender is running */
+  WM_main_add_notifier(NC_NODE | NA_EDITED, NULL);
+
+  return nt->ext.srna;
+}
+
 static IDProperty *rna_Node_idprops(PointerRNA *ptr, bool create)
 {
   bNode *node = ptr->data;
@@ -7936,6 +7972,16 @@ static void rna_def_texture_node(BlenderRNA *brna)
   RNA_def_struct_register_funcs(srna, "rna_TextureNode_register", "rna_Node_unregister", NULL);
 }
 
+static void rna_def_simulation_node(BlenderRNA *brna)
+{
+  StructRNA *srna;
+
+  srna = RNA_def_struct(brna, "SimulationNode", "NodeInternal");
+  RNA_def_struct_ui_text(srna, "Simulation Node", "");
+  RNA_def_struct_sdna(srna, "bNode");
+  RNA_def_struct_register_funcs(srna, "rna_SimulationNode_register", "rna_Node_unregister", NULL);
+}
+
 /* -------------------------------------------------------------------------- */
 
 static void rna_def_node_socket(BlenderRNA *brna)
@@ -9474,6 +9520,17 @@ static void rna_def_texture_nodetree(BlenderRNA *brna)
   RNA_def_struct_ui_icon(srna, ICON_TEXTURE);
 }
 
+static void rna_def_simulation_nodetree(BlenderRNA *brna)
+{
+  StructRNA *srna;
+
+  srna = RNA_def_struct(brna, "SimulationNodeTree", "NodeTree");
+  RNA_def_struct_ui_text(
+      srna, "Simulation Node Tree", "Node tree consisting of linked nodes used for simulations");
+  RNA_def_struct_sdna(srna, "bNodeTree");
+  RNA_def_struct_ui_icon(srna, ICON_PHYSICS); /* TODO: Use correct icon. */
+}
+
 static StructRNA *define_specific_node(BlenderRNA *brna,
                                        const char *struct_name,
                                        const char *base_name,
@@ -9560,6 +9617,7 @@ void RNA_def_nodetree(BlenderRNA *brna)
   rna_def_shader_node(brna);
   rna_def_compositor_node(brna);
   rna_def_texture_node(brna);
+  rna_def_simulation_node(brna);
 
   rna_def_nodetree(brna);
 
@@ -9568,6 +9626,7 @@ void RNA_def_nodetree(BlenderRNA *brna)
   rna_def_composite_nodetree(brna);
   rna_def_shader_nodetree(brna);
   rna_def_texture_nodetree(brna);
+  rna_def_simulation_nodetree(brna);
 
 #  define DefNode(Category, ID, DefFunc, EnumName, StructName, UIName, UIDesc) \
     { \
@@ -9584,12 +9643,13 @@ void RNA_def_nodetree(BlenderRNA *brna)
    */
 #  include "../../nodes/NOD_static_types.h"
 
-  /* Node group types need to be defined for shader, compositor, texture nodes individually.
-   * Cannot use the static types header for this, since they share the same int id.
+  /* Node group types need to be defined for shader, compositor, texture, simulation nodes
+   * individually. Cannot use the static types header for this, since they share the same int id.
    */
   define_specific_node(brna, "ShaderNodeGroup", "ShaderNode", "Group", "", def_group);
   define_specific_node(brna, "CompositorNodeGroup", "CompositorNode", "Group", "", def_group);
   define_specific_node(brna, "TextureNodeGroup", "TextureNode", "Group", "", def_group);
+  define_specific_node(brna, "SimulationNodeGroup", "SimulationNode", "Group", "", def_group);
   def_custom_group(brna,
                    "ShaderNodeCustomGroup",
                    "ShaderNode",
diff --git a/source/blender/nodes/CMakeLists.txt b/source/blender/nodes/CMakeLists.txt
index a2f825ee454..59a0ee808f5 100644
--- a/source/blender/nodes/CMakeLists.txt
+++ b/source/blender/nodes/CMakeLists.txt
@@ -23,6 +23,7 @@ set(INC
   composite
   intern
   shader
+  simulation
   texture
   ../blenkernel
   ../blenlib
@@ -220,6 +221,10 @@ set(SRC
   shader/node_shader_tree.c
   shader/node_shader_util.c
 
+  simulation/nodes/node_sim_common.cc
+  simulation/node_simulation_tree.cc
+  simulation/node_simulation_util.cc
+
   texture/nodes/node_texture_at.c
   texture/nodes/node_texture_bricks.c
   texture/nodes/node_texture_checker.c
@@ -253,11 +258,13 @@ set(SRC
 
   composite/node_composite_util.h
   shader/node_shader_util.h
+  simulation/node_simulation_util.h
   texture/node_texture_util.h
 
   NOD_common.h
   NOD_composite.h
   NOD_shader.h
+  NOD_simulation.h
   NOD_socket.h
   NOD_static_types.h
   NOD_texture.h
diff --git a/source/blender/nodes/NOD_common.h b/source/blender/nodes/NOD_common.h
index 26c78eab4ec..dcc4f4d0b76 100644
--- a/source/blender/nodes/NOD_common.h
+++ b/source/blender/nodes/NOD_common.h
@@ -26,6 +26,10 @@
 
 #include "BKE_node.h"
 
+#ifdef __cplusplus
+extern "C" {
+#endif
+
 void register_node_type_frame(void);
 void register_node_type_reroute(void);
 
@@ -42,4 +46,8 @@ struct bNodeSocket *node_group_output_find_socket(struct bNode *node, const char
 void node_group_input_update(struct bNodeTree *ntree, struct bNode *node);
 void node_group_output_update(struct bNodeTree *ntree, struct bNode *node);
 
+#ifdef __cplusplus
+}
+#endif
+
 #endif /* __NOD_COMMON_H__ */
diff --git a/source/blender/nodes/NOD_simulation.h b/source/blender/nodes/NOD_simulation.h
new file mode 100644
index 00000000000..6eca04c2acd
--- /dev/null
+++ b/source/blender/nodes/NOD_simulation.h
@@ -0,0 +1,18 @@
+#ifndef __NOD_SIMULATION_H__
+#define __NOD_SIMULATION_H__
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+extern struct bNodeTreeType *ntreeType_Simulation;
+
+void register_node_tree_type_sim(void);
+
+void register_node_type_sim_group(void);
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif /* __NOD_SIMULATION_H__ */
diff --git a/source/blender/nodes/intern/node_common.h b/source/blender/nodes/intern/node_common.h
index c3314ae3c28..7810e9f1f14 100644
--- a/source/blender/nodes/intern/node_common.h
+++ b/source/blender/nodes/intern/node_common.h
@@ -26,6 +26,10 @@
 
 #include "DNA_listBase.h"
 
+#ifdef __cplusplus
+extern "C" {
+#endif
+
 struct bNodeTree;
 
 void node_group_label(struct bNodeTree *ntree, struct bNode *node, char *label, int maxlen);
@@ -33,4 +37,8 @@ bool node_group_poll_instance(struct bNode *node, struct bNodeTree *nodetree);
 
 void ntree_update_reroute_nodes(struct bNodeTree *ntree);
 
+#ifdef __cplusplus
+}
+#endif
+
 #endif
diff --git a/source/blender/nodes/intern/node_util.h b/source/blender/nodes/intern/node_util.h
index a7f09d24a70..61f8fe6809d 100644
--- a/source/blender/nodes/intern/node_util.h
+++ b/source/blender/nodes/intern/node_util.h
@@ -38,6 +38,10 @@
 
 #include "RNA_access.h"
 
+#ifdef __cplusplus
+extern "C" {
+#endif
+
 struct bNode;
 struct bNodeTree;
 
@@ -103,4 +107,8 @@ void node_socket_set_vector(struct bNodeTree *ntree,
                             struct bNodeSocket *sock,
                             const float *value);
 
+#ifdef __cplusplus
+}
+#endif
+
 #endif
diff --git a/source/blender/nodes/simulation/node_simulation_tree.cc b/source/blender/nodes/simulation/node_simulation_tree.cc
new file mode 100644
index 00000000000..0c1833bf467
--- /dev/null
+++ b/source/blender/nodes/simulation/node_simulation_tree.cc
@@ -0,0 +1,29 @@
+#include <string.h>
+
+#include "MEM_guardedalloc.h"
+
+#include "NOD_simulation.h"
+
+#include "BKE_node.h"
+
+#include "BLT_translation.h"
+
+#include "DNA_node_types.h"
+
+#include "RNA_access.h"
+
+bNodeTreeType *ntreeType_Simulation;
+
+void register_node_tree_type_sim(void)
+{
+  bNodeTreeType *tt = ntreeType_Simulation = (bNodeTreeType *)MEM_callocN(
+      sizeof(bNodeTreeType), "simulation node tree type");
+  tt->type = NTREE_SIMULATION;
+  strcpy(tt->idname, "SimulationNodeTree");
+  strcpy(tt->ui_name, N_("Simulation Editor"));
+  tt->ui_icon = 0; /* defined in drawnode.c */
+  strcpy(tt->ui_description, N_("Simulation nodes"));
+  tt->ext.srna = &RNA_SimulationNodeTree;
+
+  ntreeTypeAdd(tt);
+}
diff --git a/source/blender/nodes/simulation/node_simulation_util.cc b/source/blender/nodes/simulation/node_simulation_util.cc
new file mode 100644
index 00000000000..c10bac1681c
--- /dev/null
+++ b/source/blender/nodes/simulation/node_simulation_util.cc
@@ -0,0 +1,13 @@
+#include "node_simulation_util.h"
+#include "node_util.h"
+
+bool sim_node_poll_default(bNodeType *UNUSED(ntype), bNodeTree *ntree)
+{
+  return STREQ(ntree->idname, "SimulationNodeTree");
+}
+
+void sim_node_type_base(bNodeType *ntype, int type, const char *name, short nclass, short flag)
+{
+  node_type_base(ntype, type, name, nclass, flag);
+  ntype->poll = sim_node_poll_default;
+}
diff --git a/source/blender/nodes/simulation/node_simulation_util.h b/source/blender/nodes/simulation/node_simulation_util.h
new file mode 100644
index 00000000000..c1ff82cd26f
--- /dev/null
+++ b/source/blender/nodes/simulation/node_simulation_util.h
@@ -0,0 +1,24 @@
+#ifndef __NODE_SIM_UTIL_H__
+#define __NODE_SIM_UTIL_H__
+
+#include <string.h>
+
+#include "BLI_utildefines.h"
+
+#include "MEM_guardedalloc.h"
+
+#include "DNA_node_types.h"
+
+#include "BKE_node.h"
+
+#include "BLT_translation.h"
+
+#include "NOD_simulation.h"
+
+#include "node_util.h"
+
+void sim_node_type_base(
+    struct bNodeType *ntype, int type, const char *name, short nclass, short flag);
+bool sim_node_poll_default(struct bNodeType *ntype, struct bNodeTree *ntree);
+
+#endif /* __NODE_SIM_UTIL_H__ */
diff --git a/source/blender/nodes/simulation/nodes/node_sim_common.cc b/source/blender/nodes/simulation/nodes/node_sim_common.cc
new file mode 100644
index 00000000000..60d47a4e290
--- /dev/null
+++ b/source/blender/nodes/simulation/nodes/node_sim_common.cc
@@ -0,0 +1,29 @@
+#include "BKE_node.h"
+
+#include "NOD_simulation.h"
+
+#include "NOD_common.h"
+#include "node_common.h"
+#include "node_simulation_util.h"
+
+void register_node_type_sim_group(void)
+{
+  static bNodeType ntype;
+
+  node_type_base_custom(&ntype, "SimulationNodeGroup", "Group", 0, 0);
+  ntype.type = NODE_GROUP;
+  ntype.poll = sim_node_poll_default;
+  ntype.poll_instance = node_group_poll_instance;
+  ntype.insert_link = node_insert_link_default;
+  ntype.update_internal_links = node_update_internal_links_default;
+  ntype.ext.srna = RNA_struct_find("SimulationNodeGroup");
+  BLI_assert(ntype.ext.srna != NULL);
+  RNA_struct_blender_type_set(ntype.ext.srna, &ntype);
+
+  node_type_socket_templates(&ntype, NULL, NULL);
+  node_type_size(&ntype, 140, 60, 400);
+  node_type_label(&ntype, node_group_label);
+  node_type_group_update(&ntype, node_group_update);
+
+  nodeRegisterType(&ntype);
+}