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Implementing-an-own-brush.md

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-TODO
+Implementing an own brush is quite easy.  
+All you need to do is implementing the _IBrush_-interface which looks like this:
+```C#
+public interface IBrush
+{
+    float Brightness { get; set; }
+    float Opacity { get; set; }
+    Color GetColorAtPoint(RectangleF rectangle, PointF point);
+}
+```
+
+> **Since the _Brightness_ and _Opacity_ is something generic you should always derive from the [_AbstractBrush_-](https://github.com/DarthAffe/CUE.NET/blob/master/Brushes/AbstractBrush.cs)Class.**  
+> If you do this, you'll only have to implement the _GetColorAtPoint_-method.
+
+In the _GetColorAtPoint_-method you'll have to calculate and return the color of one specific point (representing a key) inside a rectangle (representing the keyboard or keygroup). Both, the point and the rectangle are given as parameters.  
+
+> Before you return your calculated Color you should always call the _FinalizeColor_-method to apply the overall brightness and opacity.  
+> If you don't derive from the _AbstractBrush_-Class you'll have to to take care about this by yourself.   
+
+If you need a reference on how the implementation might look, you can take the [_LinearGradientBrush_](https://github.com/DarthAffe/CUE.NET/blob/master/Brushes/LinearGradientBrush.cs), the [_RadialGradientBrush_](https://github.com/DarthAffe/CUE.NET/blob/master/Brushes/RadialGradientBrush.cs) or the [_SolidColorBrush_](https://github.com/DarthAffe/CUE.NET/blob/master/Brushes/SolidColorBrush.cs).