Changed color-control to brushes, improved keygroups

Helper/RectangleHelper.cs

@@ -1,10 +1,16 @@
 using System;
+using System.Collections.Generic;
 using System.Drawing;
 
 namespace CUE.NET.Helper
 {
     public static class RectangleHelper
     {
+        public static PointF GetCenter(this RectangleF rectangle)
+        {
+            return new PointF(rectangle.Left + rectangle.Width / 2f, rectangle.Top + rectangle.Height / 2f);
+        }
+
         public static RectangleF CreateRectangleFromPoints(PointF point1, PointF point2)
         {
             float posX = Math.Min(point1.X, point2.X);
@@ -25,6 +31,24 @@ namespace CUE.NET.Helper
             return new RectangleF(posX, posY, width, height);
         }
 
+        public static RectangleF CreateRectangleFromRectangles(IEnumerable<RectangleF> rectangles)
+        {
+            float posX = float.MaxValue;
+            float posY = float.MaxValue;
+            float posX2 = float.MinValue;
+            float posY2 = float.MinValue;
+
+            foreach (RectangleF rectangle in rectangles)
+            {
+                posX = Math.Min(posX, rectangle.X);
+                posY = Math.Min(posY, rectangle.Y);
+                posX2 = Math.Max(posX2, rectangle.X + rectangle.Width);
+                posY2 = Math.Max(posY2, rectangle.Y + rectangle.Height);
+            }
+
+            return CreateRectangleFromPoints(new PointF(posX, posY), new PointF(posX2, posY2));
+        }
+
         public static float CalculateIntersectPercentage(RectangleF rect, RectangleF referenceRect)
         {
             if (rect.IsEmpty || referenceRect.IsEmpty) return 0;