Simulations: Embed simulation node tree in simulation data block

This adds an embedded node tree to the simulation data block dna.
The UI in the `Simulation Editor` has been updated to show a list
of simulation data blocks, instead of individual node trees.

The new `SpaceNodeEditor.simulation` property wraps the existing
`SpaceNodeEditor.id` property. It allows scripts to get and set
the simulation data block that is being edited.

Reviewers: brecht, mont29

Differential Revision: https://developer.blender.org/D7301

2 files changed, 40 insertions, 0 deletions

diff --git a/release/scripts/startup/bl_operators/__init__.py b/release/scripts/startup/bl_operators/__init__.py
index 5af2bd22222..d7df29f1769 100644
--- a/release/scripts/startup/bl_operators/__init__.py
+++ b/release/scripts/startup/bl_operators/__init__.py
@@ -42,6 +42,7 @@ _modules = [
     "rigidbody",
     "screen_play_rendered_anim",
     "sequencer",
+    "simulation",
     "userpref",
     "uvcalc_follow_active",
     "uvcalc_lightmap",
diff --git a/release/scripts/startup/bl_operators/simulation.py b/release/scripts/startup/bl_operators/simulation.py
new file mode 100644
index 00000000000..5d9c9476318
--- /dev/null
+++ b/release/scripts/startup/bl_operators/simulation.py
@@ -0,0 +1,39 @@
+# ##### 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.
+#
+# ##### END GPL LICENSE BLOCK #####
+
+import bpy
+
+class NewSimulation(bpy.types.Operator):
+    """Create a new simulation data block and edit it in the opened simulation editor"""
+
+    bl_idname = "simulation.new"
+    bl_label = "New Simulation"
+    bl_options = {'REGISTER', 'UNDO'}
+
+    @classmethod
+    def poll(cls, context):
+        return context.area.type == 'NODE_EDITOR' and context.space_data.tree_type == 'SimulationNodeTree'
+
+    def execute(self, context):
+        simulation = bpy.data.simulations.new("Simulation")
+        context.space_data.simulation = simulation
+        return {'FINISHED'}
+
+classes = (
+    NewSimulation,
+)