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, 112 insertions, 0 deletions

diff --git a/source/blender/makesrna/intern/rna_depsgraph.c b/source/blender/makesrna/intern/rna_depsgraph.c
new file mode 100644
index 00000000000..8ac1e2acc60
--- /dev/null
+++ b/source/blender/makesrna/intern/rna_depsgraph.c
@@ -0,0 +1,112 @@
+/*
+ * ***** 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.
+ *
+ * Contributor(s): Blender Foundation (2014).
+ *
+ * ***** END GPL LICENSE BLOCK *****
+ */
+
+/** \file blender/makesrna/intern/rna_depsgraph.c
+ *  \ingroup RNA
+ */
+
+#include <stdlib.h>
+
+#include "BLI_utildefines.h"
+#include "BLI_path_util.h"
+
+#include "RNA_define.h"
+#include "RNA_enum_types.h"
+
+#include "rna_internal.h"
+
+#include "DEG_depsgraph.h"
+
+#include "BKE_depsgraph.h"
+
+#ifdef RNA_RUNTIME
+
+#include "BKE_report.h"
+
+#include "DEG_depsgraph_debug.h"
+
+static void rna_Depsgraph_debug_graphviz(Depsgraph *graph, const char *filename)
+{
+	FILE *f = fopen(filename, "w");
+	if (f == NULL)
+		return;
+	
+	DEG_debug_graphviz(graph, f, "Depsgraph", false);
+	
+	fclose(f);
+}
+
+static void rna_Depsgraph_debug_rebuild(Depsgraph *UNUSED(graph), Main *bmain)
+{
+	Scene *sce;
+	DAG_relations_tag_update(bmain);
+	for (sce = bmain->scene.first; sce; sce = sce->id.next) {
+		DAG_scene_relations_rebuild(bmain, sce);
+		DEG_graph_on_visible_update(bmain, sce);
+	}
+}
+
+static void rna_Depsgraph_debug_stats(Depsgraph *graph, ReportList *reports)
+{
+	size_t outer, ops, rels;
+	
+	DEG_stats_simple(graph, &outer, &ops, &rels);
+	
+	// XXX: report doesn't seem to work
+	printf("Approx %lu Operations, %lu Relations, %lu Outer Nodes\n",
+	       ops, rels, outer);
+		   
+	BKE_reportf(reports, RPT_WARNING, "Approx. %lu Operations, %lu Relations, %lu Outer Nodes",
+	            ops, rels, outer);
+}
+
+#else
+
+static void rna_def_depsgraph(BlenderRNA *brna)
+{
+	StructRNA *srna;
+	FunctionRNA *func;
+	PropertyRNA *parm;
+
+	srna = RNA_def_struct(brna, "Depsgraph", NULL);
+	RNA_def_struct_ui_text(srna, "Dependency Graph", "");
+	
+	func = RNA_def_function(srna, "debug_graphviz", "rna_Depsgraph_debug_graphviz");
+	parm = RNA_def_string_file_path(func, "filename", NULL, FILE_MAX, "File Name",
+	                                "File in which to store graphviz debug output");
+	RNA_def_property_flag(parm, PROP_REQUIRED);
+
+	func = RNA_def_function(srna, "debug_rebuild", "rna_Depsgraph_debug_rebuild");
+	RNA_def_function_flag(func, FUNC_USE_MAIN);
+	RNA_def_property_flag(parm, PROP_REQUIRED);
+	
+	func = RNA_def_function(srna, "debug_stats", "rna_Depsgraph_debug_stats");
+	RNA_def_function_ui_description(func, "Report the number of elements in the Dependency Graph");
+	RNA_def_function_flag(func, FUNC_USE_REPORTS);
+}
+
+void RNA_def_depsgraph(BlenderRNA *brna)
+{
+	rna_def_depsgraph(brna);
+}
+
+#endif