Introduce RenderRect for easy access to the full screen rect

VocaluxeLib/Menu/CBackground.cs

@@ -36,16 +36,11 @@ namespace VocaluxeLib.Menu
     [XmlType("Background")]
     public struct SThemeBackground
     {
-        [XmlAttributeAttribute(AttributeName = "Name")]
-        public string Name;
-        [XmlElement("Type")]
-        public EBackgroundTypes Type;
-        [XmlArray]
-        public List<string> SlideShowTextures;
-        [XmlElement("Video")]
-        public string VideoName;
-        [XmlElement("Skin")]
-        public string TextureName;
+        [XmlAttribute(AttributeName = "Name")] public string Name;
+        [XmlElement("Type")] public EBackgroundTypes Type;
+        [XmlArray] public List<string> SlideShowTextures;
+        [XmlElement("Video")] public string VideoName;
+        [XmlElement("Skin")] public string TextureName;
         public SThemeColor Color;
     }
 
@@ -225,7 +220,9 @@ namespace VocaluxeLib.Menu
         #region internal
         private static SRectF _GetDrawRect()
         {
-            return new SRectF(0f, 0f, CBase.Settings.GetRenderW(), CBase.Settings.GetRenderH(), CBase.Settings.GetZFar() / 4);
+            SRectF rect = CBase.Settings.GetRenderRect();
+            rect.Z = CBase.Settings.GetZFar() / 4;
+            return rect;
         }
 
         private void _DrawColor()