/// <summary>
/// Recolor a rendering element after it has been generated. Since rendering elements are
/// immutable, the input element remains unmodified.
/// </summary>
/// <param name="element">the rendering element</param>
/// <param name="color">the new color</param>
/// <returns>recolored rendering element</returns>
private static IRenderingElement Recolor(IRenderingElement element, Color color)
{
switch (element)
{
case ElementGroup orgGroup:
var newGroup = new ElementGroup();
foreach (var child in orgGroup)
{
newGroup.Add(Recolor(child, color));
}
return(newGroup);
case LineElement lineElement:
return(new LineElement(lineElement.FirstPoint, lineElement.SecondPoint, lineElement.Width, color));
case GeneralPath generalPath:
return(generalPath.Recolor(color));
}
throw new ArgumentException($"Cannot highlight rendering element, {element.GetType()}");
}
/// <summary>
/// Generate an outer glow for the provided rendering element. The glow is defined by the glow
/// width and the stroke size.
/// </summary>
/// <param name="element">rendering element</param>
/// <param name="color">color of the glow</param>
/// <param name="glowWidth">the width of the glow</param>
/// <param name="stroke">the stroke width</param>
/// <returns>generated outer glow</returns>
internal static IRenderingElement OuterGlow(IRenderingElement element, Color color, double glowWidth, double stroke)
{
switch (element)
{
case ElementGroup orgGroup:
var newGroup = new ElementGroup();
foreach (var child in orgGroup)
{
newGroup.Add(OuterGlow(child, color, glowWidth, stroke));
}
return(newGroup);
case LineElement lineElement:
return(new LineElement(lineElement.FirstPoint, lineElement.SecondPoint, stroke + (2 * (glowWidth * stroke)), color));
case GeneralPath org:
if (org.Fill)
{
return(org.Outline(2 * (glowWidth * stroke)).Recolor(color));
}
else
{
return(org.Outline(stroke + (2 * (glowWidth * stroke))).Recolor(color));
}
default:
throw new ArgumentException($"Cannot generate glow for rendering element,{element.GetType()}");
}
}