Restored Fluid Sim baking

This commit restores fluid sim baking functionality in 2.5, it's been on the todo for
a while, and was previously almost completely non-functional. The old 
code was quite complicated and specific to the 2.4 animation system, so I've 
pretty much rewritten most of it.

This includes:
* Animated variables work again - just key them in the UI. Non-animateable values
should be already set non-animateable in RNA, hopefully I got them all.

Available are: Domain Gravity / Domain Viscosity / Object loc/rot/scale / 
Object initial velocity / Deforming meshes / Fluid control Attract strength / 
Fluid control Attract radius / Fluid control Velocity strength / 
Fluid control Velocity radius / Object Active status (checkbox next to fluid type)

The Domain time scale is still not yet implemented.

* Fluid sim now use global scene units data by default - when enabled, the 
scene's global gravity value is used and when units are set (metric/imperial)
the simulation real world size is taken from the object's actual measurements.

* The baking process is now done in the background, using the nifty threaded
Jobs system. It's non-blocking and your domain object will show the simulated
fluid as it becomes available for that frame.

A nice extra thing for the future would be to improve the visualisation of the 
object's state while baking, and also the jobs system/ui could do with some
touchups - currently it has to share a bit from the 'render' job, and appears as
'Render' in the header. Progress bars for jobs in the header would be great too.

1 files changed, 31 insertions, 8 deletions

diff --git a/release/scripts/ui/properties_physics_fluid.py b/release/scripts/ui/properties_physics_fluid.py
index 9b36b98bc24..c6fd7e930d9 100644
--- a/release/scripts/ui/properties_physics_fluid.py
+++ b/release/scripts/ui/properties_physics_fluid.py
@@ -42,7 +42,7 @@ class PHYSICS_PT_fluid(PhysicButtonsPanel):
         md = context.fluid
         wide_ui = context.region.width > narrowui
 
-        split = layout.split()
+        split = layout.split(percentage=0.5)
         split.operator_context = 'EXEC_DEFAULT'
 
         if md:
@@ -53,7 +53,7 @@ class PHYSICS_PT_fluid(PhysicButtonsPanel):
             row = split.row(align=True)
             row.prop(md, "render", text="")
             row.prop(md, "realtime", text="")
-
+            
             fluid = md.settings
 
         else:
@@ -67,10 +67,19 @@ class PHYSICS_PT_fluid(PhysicButtonsPanel):
 
         if fluid:
             if wide_ui:
-                layout.prop(fluid, "type")
+                row = layout.row()
+                row.prop(fluid, "type")
+                if fluid.type not in ('NONE', 'DOMAIN', 'PARTICLE'):
+                    row.prop(fluid, "active", text="")
             else:
                 layout.prop(fluid, "type", text="")
-
+                if fluid.type not in ('NONE', 'DOMAIN', 'PARTICLE'):
+                    layout.prop(fluid, "active", text="")
+            
+            layout = layout.column()
+            if fluid.type not in ('NONE', 'DOMAIN', 'PARTICLE'):
+                layout.active = fluid.active
+            
             if fluid.type == 'DOMAIN':
                 layout.operator("fluid.bake", text="Bake Fluid Simulation", icon='MOD_FLUIDSIM')
                 split = layout.split()
@@ -220,15 +229,29 @@ class PHYSICS_PT_domain_gravity(PhysicButtonsPanel):
         layout = self.layout
 
         fluid = context.fluid.settings
+        scene = context.scene
         wide_ui = context.region.width > narrowui
 
         split = layout.split()
 
         col = split.column()
-        col.label(text="Gravity:")
-        col.prop(fluid, "gravity", text="")
-        col.label(text="Real World Size:")
-        col.prop(fluid, "real_world_size", text="Metres")
+        if scene.use_gravity:
+            col.label(text="Using Scene Gravity", icon="SCENE_DATA")
+            sub = col.column()
+            sub.enabled = False
+            sub.prop(fluid, "gravity", text="")
+        else:
+            col.label(text="Gravity:")
+            col.prop(fluid, "gravity", text="")
+        
+        if scene.unit_settings.system != 'NONE':
+            col.label(text="Using Scene Size Units", icon="SCENE_DATA")
+            sub = col.column()
+            sub.enabled = False
+            sub.prop(fluid, "real_world_size", text="Metres")
+        else:
+            col.label(text="Real World Size:")
+            col.prop(fluid, "real_world_size", text="Metres")
 
         if wide_ui:
             col = split.column()