diff --git a/Textures/Sky/cl_cumulus.rgb b/Textures/Sky/cl_cumulus.rgb
new file mode 100644
index 000000000..0185eac4d
Binary files /dev/null and b/Textures/Sky/cl_cumulus.rgb differ
diff --git a/Textures/Sky/cl_stratus.rgb b/Textures/Sky/cl_stratus.rgb
new file mode 100644
index 000000000..98dd02cfd
Binary files /dev/null and b/Textures/Sky/cl_stratus.rgb differ
diff --git a/gui/dialogs/rendering.xml b/gui/dialogs/rendering.xml
index b524cc9a1..fc4d619e2 100644
--- a/gui/dialogs/rendering.xml
+++ b/gui/dialogs/rendering.xml
@@ -1,101 +1,147 @@
-<?xml version="1.0"?>
-
-<PropertyList>
-  <name>rendering</name>
-  <modal>false</modal>
-  <layout>vbox</layout>
-
-  <text>
-    <label>Rendering Options</label>
-  </text>
-
-  <group>
-    <layout>vbox</layout>
-    <halign>center</halign>
-
-    <checkbox>
-      <halign>left</halign>
-      <label>Sun/Moon horizon effect</label>
-      <property>/sim/rendering/horizon-effect</property>
-    </checkbox>
-    
-    <checkbox>
-      <halign>left</halign>
-      <label>Enhanced runway lighting</label>
-      <property>/sim/rendering/enhanced-lighting</property>
-    </checkbox>
-    
-    <checkbox>
-      <halign>left</halign>
-      <label>Runway light distance attenuation</label>
-      <property>/sim/rendering/distance-attenuation</property>
-    </checkbox>
-    
-    <checkbox>
-      <halign>left</halign>
-      <label>Specular reflections on objects</label>
-      <property>/sim/rendering/specular-highlight</property>
-    </checkbox>
-
-    <checkbox>
-      <halign>left</halign>
-      <label>Bump mapped clouds</label>
-      <property>/sim/rendering/bump-mapping</property>
-    </checkbox>
-
-    <checkbox>
-      <halign>left</halign>
-      <label>Show frame rate</label>
-      <property>/sim/hud/draw-fps</property>
-    </checkbox>
-  </group>
-
-  <group>
-    <layout>hbox</layout>
-    <empty><stretch>true</stretch></empty>
-
-    <button>
-      <legend>OK</legend>
-      <equal>true</equal>
-      <binding>
-	<command>dialog-apply</command>
-      </binding>
-      <binding>
-	<command>dialog-close</command>
-      </binding>
-      <default>true</default>
-    </button>
-
-    <empty><stretch>true</stretch></empty>
-
-    <button>
-      <legend>Apply</legend>
-      <equal>true</equal>
-      <binding>
-	<command>dialog-apply</command>
-      </binding>
-    </button>
-
-    <empty><stretch>true</stretch></empty>
-
-    <button>
-      <legend>Reset</legend>
-      <equal>true</equal>
-      <binding>
-	<command>dialog-update</command>
-      </binding>
-    </button>
-
-    <empty><stretch>true</stretch></empty>
-
-    <button>
-      <legend>Cancel</legend>
-      <equal>true</equal>
-      <binding>
-	<command>dialog-close</command>
-      </binding>
-    </button>
-
-    <empty><stretch>true</stretch></empty>
-  </group>
-</PropertyList>
+<?xml version="1.0"?>
+
+<PropertyList>
+  <name>rendering</name>
+  <modal>false</modal>
+  <layout>vbox</layout>
+
+  <text>
+    <label>Rendering Options</label>
+  </text>
+
+  <group>
+    <layout>vbox</layout>
+    <halign>center</halign>
+
+    <checkbox>
+      <halign>left</halign>
+      <label>Sun/Moon horizon effect</label>
+      <property>/sim/rendering/horizon-effect</property>
+    </checkbox>
+    
+    <checkbox>
+      <halign>left</halign>
+      <label>Enhanced runway lighting</label>
+      <property>/sim/rendering/enhanced-lighting</property>
+    </checkbox>
+    
+    <checkbox>
+      <halign>left</halign>
+      <label>Runway light distance attenuation</label>
+      <property>/sim/rendering/distance-attenuation</property>
+    </checkbox>
+    
+    <checkbox>
+      <halign>left</halign>
+      <label>Specular reflections on objects</label>
+      <property>/sim/rendering/specular-highlight</property>
+    </checkbox>
+
+    <checkbox>
+      <halign>left</halign>
+      <label>Bump mapped clouds</label>
+      <property>/sim/rendering/bump-mapping</property>
+    </checkbox>
+
+    <checkbox>
+      <halign>left</halign>
+      <label>Show frame rate</label>
+      <property>/sim/hud/draw-fps</property>
+    </checkbox>
+
+    <checkbox>
+      <halign>left</halign>
+      <label>Enable 3d clouds</label>
+      <property>/sim/rendering/clouds3d-enable</property>
+    </checkbox>
+  </group>
+
+
+  <group>
+    <layout>hbox</layout>
+    <halign>right</halign>
+    <text><label>Visibility range (1km...50km)</label></text>
+    <slider>
+      <min>1000</min>
+      <max>50000</max>
+
+      <property>/sim/rendering/clouds3d-vis-range</property>
+      <binding>
+	<command>dialog-apply</command>
+      </binding>
+    </slider>
+  </group>
+
+  <group>
+    <layout>hbox</layout>
+    <halign>right</halign>
+    <text><label>Cloud density</label></text>
+    <slider>
+      <min>0</min>
+      <max>100</max>
+
+      <property>/sim/rendering/clouds3d-density</property>
+      <binding>
+	<command>dialog-apply</command>
+      </binding>
+    </slider>
+  </group>
+
+  <group>
+    <layout>hbox</layout>
+    <text><label>3D Clouds cache size in Kbytes</label></text>
+  <input>
+    <property>/sim/rendering/clouds3d-cache-size</property>
+  </input>  
+  </group>
+
+
+  <group>
+    <layout>hbox</layout>
+    <empty><stretch>true</stretch></empty>
+
+    <button>
+      <legend>OK</legend>
+      <equal>true</equal>
+      <binding>
+	<command>dialog-apply</command>
+      </binding>
+      <binding>
+	<command>dialog-close</command>
+      </binding>
+      <default>true</default>
+    </button>
+
+    <empty><stretch>true</stretch></empty>
+
+    <button>
+      <legend>Apply</legend>
+      <equal>true</equal>
+      <binding>
+	<command>dialog-apply</command>
+      </binding>
+    </button>
+
+    <empty><stretch>true</stretch></empty>
+
+    <button>
+      <legend>Reset</legend>
+      <equal>true</equal>
+      <binding>
+	<command>dialog-update</command>
+      </binding>
+    </button>
+
+    <empty><stretch>true</stretch></empty>
+
+    <button>
+      <legend>Cancel</legend>
+      <equal>true</equal>
+      <binding>
+	<command>dialog-close</command>
+      </binding>
+    </button>
+
+    <empty><stretch>true</stretch></empty>
+  </group>
+</PropertyList>