private static SvgPaintServer CreateLinearGradientPaintServer(SvgElement elementToPaint, SvgLinearGradientElement linear)
{
var stops = ConvertStops(linear.Stops);
if (linear.GradientTransform.Count > 0)
{
throw new NotImplementedException($"gradient '{linear.GradientTransform}' transformations");
}
var bbox = elementToPaint.GetBBox();
var width = bbox?.Width ?? 0;
var height = bbox?.Height ?? 0;
float?GetRelativeValue(SvgLength?length)
{
if (length == null)
{
return(null);
}
var lengthType = length.Value.LengthType;
if (lengthType != SvgLengthType.Number && lengthType != SvgLengthType.Percentage)
{
throw new Exception($"Expected linear gradient value to be number or percent but got '{length}'");
}
return(length.Value.GetAbsoluteValue(1));
}
var x1 = (GetRelativeValue(linear.X1) ?? 0) * width;
var y1 = (GetRelativeValue(linear.Y1) ?? 0) * height;
var x2 = (GetRelativeValue(linear.X2) ?? 1) * width;
var y2 = (GetRelativeValue(linear.Y2) ?? 0) * height;
if (Math.Abs(x1 - x2) < float.Epsilon && Math.Abs(y1 - y2) < float.Epsilon)
{
if (stops.Count < 1)
{
throw new Exception($"Linear gradient has no stops");
}
var lastStop = stops[stops.Count - 1];
return(new SvgSolidColorPaintServer(lastStop.Color, lastStop.Opacity));
}
return(new SvgLinearGradientPaintServer(x1, y1, x2, y2, linear.GradientUnits, stops));
}
private static SvgPaintServer CreateRadialGradientPaintServer(SvgElement elementToPaint, SvgRadialGradientElement radial)
{
var stops = ConvertStops(radial.Stops);
if (radial.GradientTransform.Count > 0)
{
throw new NotImplementedException($"gradient '{radial.GradientTransform}' transformations");
}
var bbox = elementToPaint.GetBBox();
var width = bbox?.Width ?? 0;
var height = bbox?.Height ?? 0;
var cx = radial.CircleX?.GetAbsoluteValue(width) ?? (width * 0.5f);
var cy = radial.CircleY?.GetAbsoluteValue(height) ?? (height * 0.5f);
var cr = radial.CircleRadius?.GetAbsoluteValue(width) ?? (width * 0.5f);
var fx = radial.FocalX?.GetAbsoluteValue(width) ?? cx;
var fy = radial.FocalY?.GetAbsoluteValue(height) ?? cy;
return(new SvgRadialGradientPaintServer(cx, cy, cr, fx, fy, radial.GradientUnits, stops));
}