Depsgraph: New dependency graph integration commit

This commit integrates the work done so far on the new dependency graph system,
where goal was to replace legacy depsgraph with the new one, supporting loads of
neat features like:

- More granular dependency relation nature, which solves issues with fake cycles
  in the dependencies.

- Move towards all-animatable, by better integration of drivers into the system.

- Lay down some basis for upcoming copy-on-write, overrides and so on.

The new system is living side-by-side with the previous one and disabled by
default, so nothing will become suddenly broken. The way to enable new depsgraph
is to pass `--new-depsgraph` command line argument.

It's a bit early to consider the system production-ready, there are some TODOs
and issues were discovered during the merge period, they'll be addressed ASAP.
But it's important to merge, because it's the only way to attract artists to
really start testing this system.

There are number of assorted documents related on the design of the new system:

* http://wiki.blender.org/index.php/User:Aligorith/GSoC2013_Depsgraph#Design_Documents
* http://wiki.blender.org/index.php/User:Nazg-gul/DependencyGraph

There are also some user-related information online:

* http://code.blender.org/2015/02/blender-dependency-graph-branch-for-users/
* http://code.blender.org/2015/03/more-dependency-graph-tricks/

Kudos to everyone who was involved into the project:

- Joshua "Aligorith" Leung -- design specification, initial code
- Lukas "lukas_t" Toenne -- integrating code into blender, with further fixes
- Sergey "Sergey" "Sharybin" -- some mocking around, trying to wrap up the
  project and so
- Bassam "slikdigit" Kurdali -- stressing the new system, reporting all the
  issues and recording/writing documentation.
- Everyone else who i forgot to mention here :)

1 files changed, 117 insertions, 0 deletions

diff --git a/source/blender/depsgraph/DEG_depsgraph_build.h b/source/blender/depsgraph/DEG_depsgraph_build.h
new file mode 100644
index 00000000000..08b83ac2ea1
--- /dev/null
+++ b/source/blender/depsgraph/DEG_depsgraph_build.h
@@ -0,0 +1,117 @@
+/*
+ * ***** BEGIN GPL LICENSE BLOCK *****
+ *
+ * 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.
+ *
+ * The Original Code is Copyright (C) 2013 Blender Foundation.
+ * All rights reserved.
+ *
+ * Original Author: Joshua Leung
+ * Contributor(s): Lukas Toenne
+ *
+ * ***** END GPL LICENSE BLOCK *****
+ *
+ * Public API for Depsgraph
+ */
+
+#ifndef __DEG_DEPSGRAPH_BUILD_H__
+#define __DEG_DEPSGRAPH_BUILD_H__
+
+/* ************************************************* */
+
+/* Dependency Graph */
+struct Depsgraph;
+
+/* ------------------------------------------------ */
+
+struct Main;
+struct Scene;
+
+struct PointerRNA;
+struct PropertyRNA;
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+/* Graph Building -------------------------------- */
+
+/* Build depsgraph for the given scene, and dump results in given graph container */
+void DEG_graph_build_from_scene(struct Depsgraph *graph, struct Main *bmain, struct Scene *scene);
+
+/* Tag relations from the given graph for update. */
+void DEG_graph_tag_relations_update(struct Depsgraph *graph);
+
+/* Tag all relations in the database for update.*/
+void DEG_relations_tag_update(struct Main *bmain);
+
+/* Create new graph if didn't exist yet,
+ * or update relations if graph was tagged for update.
+ */
+void DEG_scene_relations_update(struct Main *bmain, struct Scene *scene);
+
+/* Rebuild dependency graph only for a given scene. */
+void DEG_scene_relations_rebuild(struct Main *bmain,
+                                 struct Scene *scene);
+
+/* Delete scene graph. */
+void DEG_scene_graph_free(struct Scene *scene);
+
+/* Add Dependencies  ----------------------------- */
+
+/* Handle for components to define their dependencies from callbacks.
+ * This is generated by the depsgraph and passed to dependency callbacks
+ * as a symbolic reference to the current DepsNode.
+ * All relations will be defined in reference to that node.
+ */
+struct DepsNodeHandle;
+
+struct Object;
+
+typedef enum eDepsSceneComponentType {
+	DEG_SCENE_COMP_PARAMETERS,     /* Parameters Component - Default when nothing else fits (i.e. just SDNA property setting) */
+	DEG_SCENE_COMP_ANIMATION,      /* Animation Component */                 // XXX: merge in with parameters?
+	DEG_SCENE_COMP_SEQUENCER,      /* Sequencer Component (Scene Only) */
+} eDepsSceneComponentType;
+
+typedef enum eDepsObjectComponentType {
+	DEG_OB_COMP_PARAMETERS,        /* Parameters Component - Default when nothing else fits (i.e. just SDNA property setting) */
+	DEG_OB_COMP_PROXY,             /* Generic "Proxy-Inherit" Component */   // XXX: Also for instancing of subgraphs?
+	DEG_OB_COMP_ANIMATION,         /* Animation Component */                 // XXX: merge in with parameters?
+	DEG_OB_COMP_TRANSFORM,         /* Transform Component (Parenting/Constraints) */
+	DEG_OB_COMP_GEOMETRY,          /* Geometry Component (DerivedMesh/Displist) */
+	
+	/* Evaluation-Related Outer Types (with Subdata) */
+	DEG_OB_COMP_EVAL_POSE,         /* Pose Component - Owner/Container of Bones Eval */
+	DEG_OB_COMP_BONE,              /* Bone Component - Child/Subcomponent of Pose */
+	
+	DEG_OB_COMP_EVAL_PARTICLES,    /* Particle Systems Component */
+	DEG_OB_COMP_SHADING,           /* Material Shading Component */
+} eDepsObjectComponentType;
+
+void DEG_add_scene_relation(struct DepsNodeHandle *node, struct Scene *scene, eDepsSceneComponentType component, const char *description);
+void DEG_add_object_relation(struct DepsNodeHandle *node, struct Object *ob, eDepsObjectComponentType component, const char *description);
+void DEG_add_bone_relation(struct DepsNodeHandle *handle, struct Object *ob, const char *bone_name, eDepsObjectComponentType component, const char *description);
+
+/* TODO(sergey): Remove once all geometry update is granular. */
+void DEG_add_special_eval_flag(struct Depsgraph *graph, struct ID *id, short flag);
+
+/* ************************************************ */
+
+#ifdef __cplusplus
+} /* extern "C" */
+#endif
+
+#endif  /* __DEG_DEPSGRAPH_BUILD_H__ */