scripts/startup/bl_ui/properties_physics_fluid.py

@@ -1055,51 +1055,6 @@ class PHYSICS_PT_particles(PhysicButtonsPanel, Panel):
                 split.operator("fluid.free_particles", text="Free Particles")
 
 
-class PHYSICS_PT_viscosity(PhysicButtonsPanel, Panel):
-    bl_label = "Viscosity"
-    bl_parent_id = "PHYSICS_PT_liquid"
-    bl_options = {'DEFAULT_CLOSED'}
-    COMPAT_ENGINES = {
-        'BLENDER_RENDER',
-        'BLENDER_EEVEE',
-        'BLENDER_EEVEE_NEXT',
-        'BLENDER_WORKBENCH',
-    }
-
-    @classmethod
-    def poll(cls, context):
-        # Fluid viscosity only enabled for liquids
-        if not PhysicButtonsPanel.poll_liquid_domain(context):
-            return False
-
-        return (context.engine in cls.COMPAT_ENGINES)
-
-    def draw_header(self, context):
-        md = context.fluid.domain_settings
-        domain = context.fluid.domain_settings
-        is_baking_any = domain.is_cache_baking_any
-        has_baked_any = domain.has_cache_baked_any
-        self.layout.enabled = not is_baking_any and not has_baked_any
-        self.layout.prop(md, "use_viscosity", text="")
-
-    def draw(self, context):
-        layout = self.layout
-        layout.use_property_split = True
-
-        domain = context.fluid.domain_settings
-        layout.active = domain.use_viscosity
-
-        is_baking_any = domain.is_cache_baking_any
-        has_baked_any = domain.has_cache_baked_any
-        has_baked_data = domain.has_cache_baked_data
-
-        flow = layout.grid_flow(row_major=True, columns=0, even_columns=True, even_rows=False, align=False)
-        flow.enabled = not is_baking_any and not has_baked_any and not has_baked_data
-
-        col = flow.column(align=True)
-        col.prop(domain, "viscosity_value", text="Strength")
-
-
 class PHYSICS_PT_diffusion(PhysicButtonsPanel, Panel):
     bl_label = "Diffusion"
     bl_parent_id = "PHYSICS_PT_liquid"
@@ -1152,6 +1107,51 @@ class PHYSICS_PT_diffusion(PhysicButtonsPanel, Panel):
         col.prop(domain, "surface_tension", text="Surface Tension")
 
 
+class PHYSICS_PT_viscosity(PhysicButtonsPanel, Panel):
+    bl_label = "High Viscosity Solver"
+    bl_parent_id = "PHYSICS_PT_diffusion"
+    bl_options = {'DEFAULT_CLOSED'}
+    COMPAT_ENGINES = {
+        'BLENDER_RENDER',
+        'BLENDER_EEVEE',
+        'BLENDER_EEVEE_NEXT',
+        'BLENDER_WORKBENCH',
+    }
+
+    @classmethod
+    def poll(cls, context):
+        # Fluid viscosity only enabled for liquids
+        if not PhysicButtonsPanel.poll_liquid_domain(context):
+            return False
+
+        return (context.engine in cls.COMPAT_ENGINES)
+
+    def draw_header(self, context):
+        md = context.fluid.domain_settings
+        domain = context.fluid.domain_settings
+        is_baking_any = domain.is_cache_baking_any
+        has_baked_any = domain.has_cache_baked_any
+        self.layout.enabled = not is_baking_any and not has_baked_any
+        self.layout.prop(md, "use_viscosity", text="")
+
+    def draw(self, context):
+        layout = self.layout
+        layout.use_property_split = True
+
+        domain = context.fluid.domain_settings
+        layout.active = domain.use_viscosity
+
+        is_baking_any = domain.is_cache_baking_any
+        has_baked_any = domain.has_cache_baked_any
+        has_baked_data = domain.has_cache_baked_data
+
+        flow = layout.grid_flow(row_major=True, columns=0, even_columns=True, even_rows=False, align=False)
+        flow.enabled = not is_baking_any and not has_baked_any and not has_baked_data
+
+        col = flow.column(align=True)
+        col.prop(domain, "viscosity_value", text="Strength")
+
+
 class PHYSICS_PT_guide(PhysicButtonsPanel, Panel):
     bl_label = "Guides"
     bl_parent_id = "PHYSICS_PT_fluid"
@@ -1625,8 +1625,8 @@ classes = (
     PHYSICS_PT_noise,
     PHYSICS_PT_fire,
     PHYSICS_PT_liquid,
-    PHYSICS_PT_viscosity,
     PHYSICS_PT_diffusion,
+    PHYSICS_PT_viscosity,
     PHYSICS_PT_particles,
     PHYSICS_PT_mesh,
     PHYSICS_PT_guide,

source/blender/makesrna/intern/rna_fluid.cc

@@ -1904,7 +1904,8 @@ static void rna_def_fluid_domain_settings(BlenderRNA *brna)
 
   prop = RNA_def_property(srna, "use_viscosity", PROP_BOOLEAN, PROP_NONE);
   RNA_def_property_boolean_sdna(prop, nullptr, "flags", FLUID_DOMAIN_USE_VISCOSITY);
-  RNA_def_property_ui_text(prop, "Use Viscosity", "Enable fluid viscosity settings");
+  RNA_def_property_ui_text(
+      prop, "Use Viscosity", "Simulate fluids with high viscosity using a special solver");
   RNA_def_property_update(prop, NC_OBJECT | ND_MODIFIER, "rna_Fluid_datacache_reset");
 
   prop = RNA_def_property(srna, "viscosity_value", PROP_FLOAT, PROP_NONE);