Simulations: 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.

The node tree will initially be used for the new particle nodes system.

When the cmake option `WITH_NEW_SIMULATION_TYPE` is enabled, a new
`Simulation Editor` is shown in the editors menu (which is just a node editor).

This patch does not add entries to the Add Node menu, so it is empty.

Reviewers: brecht

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

6 files changed, 32 insertions, 2 deletions

diff --git a/source/blender/editors/include/ED_node.h b/source/blender/editors/include/ED_node.h
index dfdd809dbd1..1dc98cfee2f 100644
--- a/source/blender/editors/include/ED_node.h
+++ b/source/blender/editors/include/ED_node.h
@@ -99,6 +99,7 @@ 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 e5ca2efb26f..01fbafe6176 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 a82acfc4dbe..bd5ce135f82 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 3a0ef45a68d..2617384d046 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 b6ee393b991..30fe9a1ed11 100644
--- a/source/blender/editors/space_node/space_node.c
+++ b/source/blender/editors/space_node/space_node.c
@@ -938,6 +938,11 @@ 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) {