C# - Bild steht auf reflektierendem Grund

/// <summary>
/// Lets appear a picture standing on a reflecting ground.
/// </summary>
/// <param name="source">Image to apply effect to</param>
/// <param name="height">Height of the reflection (percentage)</param>
/// <param name="startTransparency">
///     transparency the effect starts with
/// </param>
/// <param name="BackgroundColor">Color of the ground</param>
/// <returns>a bitmap with the desired effect</returns>
private Bitmap ReflectingGround(Image source, byte height, 
    byte startTransparency, Color BackgroundColor)
{
    // height needed for the shadow
    int shadowHeight = Convert.ToInt32(
        Convert.ToDouble(height) / 100 * source.Height);

    // create new bitmap for the generated picture
    Bitmap myBitmap = new Bitmap(source.Width, 
        source.Height + shadowHeight);

    Graphics myGraphics = Graphics.FromImage(myBitmap);

    // draw the source image
    myGraphics.DrawImage(source, 0, 0);

    // flip the source image and draw it below the source image
    Image flipped = (Image)source.Clone();
    flipped.RotateFlip(RotateFlipType.RotateNoneFlipY);

    myGraphics.DrawImage(flipped, 0, source.Height);

    // create gradient from semi-transparent to transparent over
    // the flipped copy
    Rectangle gradientRect = new Rectangle(0, source.Height, 
        source.Width, shadowHeight);

    // create brush
    System.Drawing.Drawing2D.LinearGradientBrush myBrush = 
        new System.Drawing.Drawing2D.LinearGradientBrush(
        gradientRect, 
        Color.FromArgb(startTransparency, BackgroundColor), 
        Color.FromArgb(255, BackgroundColor),
        System.Drawing.Drawing2D.LinearGradientMode.Vertical);

    // draw gradient
    myGraphics.FillRectangle(myBrush, gradientRect);

    // return created bitmap
    return myBitmap;
}