Question

Does anyone know if there is an equilant attribute of SVG’s “gradientUnits=userSpaceOnUse” in WPF for a LinearGradientBrush? I can’t seem to find this.

If not, does anyone know about how to calculate it in (C# or VB.NET)? For example if I have a StartPoint of 0,0 and EndPoint of 1,1 on a Rectangle that is 100×100, the angle is 45 degrees. However, when I change either the width or height of the Rectangle, for example Width=150, the axis is no longer at 45 degrees. How could I calculate to keep the angle at 45 degrees in a rectangle that is not a square so that it runs from bottom left to top right corner for a middle gradientstop.

Answer 1

This works like a charm now in the new Silverlight 4 – setting the angle to 45 degrees in RotateTransform does so for the bounding box instead of the shape. Like this:

  <Rectangle Width="70" Height="50">
    <Rectangle.Fill>
        <LinearGradientBrush  EndPoint="0.5,1" StartPoint="0.5,0">
            <GradientStop Color="#FFF70202" Offset="0"/>
            <GradientStop Color="#FFF7F206" Offset="1"/>
            <GradientStop Color="Black" Offset="0.49"/>
            <GradientStop Color="Black" Offset="0.51"/>
            <GradientStop Color="White" Offset="0.5"/>
            <LinearGradientBrush.RelativeTransform>
            <RotateTransform CenterX="0.5" CenterY="0.5" Angle="45"></RotateTransform>
            </LinearGradientBrush.RelativeTransform>
        </LinearGradientBrush>
    </Rectangle.Fill>