Fluid: Hide Advanced cache options

The Manta script export should not be visible in the UI. At least not to normal users. The export feature is only useful for developers.

release/scripts/startup/bl_ui/properties_physics_fluid.py

@@ -1141,7 +1141,8 @@ class PHYSICS_PT_export(PhysicButtonsPanel, Panel):
 
     @classmethod
     def poll(cls, context):
-        if not PhysicButtonsPanel.poll_fluid_domain(context):
+        # Only show the advanced panel to advanced users who know Mantaflow's birthday :)
+        if not PhysicButtonsPanel.poll_fluid_domain(context) or bpy.app.debug_value != 3001:
             return False
 
         return (context.engine in cls.COMPAT_ENGINES)

source/blender/blenkernel/BKE_global.h

@@ -77,6 +77,7 @@ typedef struct Global {
    *   *    799: Enable some mysterious new depsgraph behavior (05/2015).
    *   *   1112: Disable new Cloth internal springs handling (09/2014).
    *   *   1234: Disable new dyntopo code fixing skinny faces generation (04/2015).
+   *   *   3001: Enable additional Fluid modifier (Mantaflow) options (02/2020).
    *   * 16384 and above: Reserved for python (add-ons) usage.
    */
   short debug_value;