Simulations: UI for core particle nodes

This commit adds the initial set of particles nodes. These are fairly
low level and are expected to be put into groups that we ship with Blender.

See D7384 for a description of the individual nodes.

Reviewers: brecht

Differential Revision: https://developer.blender.org/D7384

release/scripts/startup/nodeitems_builtins.py

@@ -477,6 +477,30 @@ texture_node_categories = [
 
 simulation_node_categories = [
     # Simulation Nodes
+    SimulationNodeCategory("SIM_OUTPUT", "Output", items=[
+        NodeItem("SimulationNodeParticleSimulation"),
+    ]),
+    SimulationNodeCategory("SIM_INPUTS", "Input", items=[
+        NodeItem("SimulationNodeTime"),
+        NodeItem("SimulationNodeParticleAttribute"),
+    ]),
+    SimulationNodeCategory("SIM_EMITTERS", "Emitters", items=[
+        NodeItem("SimulationNodeParticleMeshEmitter"),
+        NodeItem("SimulationNodeEmitParticles"),
+    ]),
+    SimulationNodeCategory("SIM_EVENTS", "Events", items=[
+        NodeItem("SimulationNodeParticleBirthEvent"),
+        NodeItem("SimulationNodeParticleTimeStepEvent"),
+        NodeItem("SimulationNodeParticleMeshCollisionEvent"),
+    ]),
+    SimulationNodeCategory("SIM_FORCES", "Forces", items=[
+        NodeItem("SimulationNodeForce"),
+    ]),
+    SimulationNodeCategory("SIM_EXECUTE", "Execute", items=[
+        NodeItem("SimulationNodeSetParticleAttribute"),
+        NodeItem("SimulationNodeExecuteCondition"),
+        NodeItem("SimulationNodeMultiExecute"),
+    ]),
     SimulationNodeCategory("SIM_GROUP", "Group", items=node_group_items),
     SimulationNodeCategory("SIM_LAYOUT", "Layout", items=[
         NodeItem("NodeFrame"),