public double[] FitToViewBox(SvgRect viewBox, SvgRect rectToFit)
{
var localName = _ownerElement.LocalName;
if (string.Equals(localName, "svg", StringComparison.Ordinal)) // (_ownerElement is SvgSvgElement)
{
ISvgMatrix mat = ((SvgSvgElement)_ownerElement).ViewBoxTransform;
return(new double[] { mat.E, mat.F, mat.A, mat.D });
}
if (string.Equals(localName, "pattern", StringComparison.Ordinal)) // (_ownerElement is SvgPatternElement)
{
ISvgMatrix mat = ((SvgPatternElement)_ownerElement).ViewBoxTransform;
return(new double[] { mat.E, mat.F, mat.A, mat.D });
}
double translateX = 0;
double translateY = 0;
double scaleX = 1;
double scaleY = 1;
if (!viewBox.IsEmpty && !rectToFit.IsEmpty)
{
// calculate scale values for non-uniform scaling
scaleX = rectToFit.Width / viewBox.Width;
scaleY = rectToFit.Height / viewBox.Height;
if (_alignment != SvgPreserveAspectRatioType.None)
{
// uniform scaling
if (_meetOrSlice == SvgMeetOrSlice.Meet)
{
scaleX = Math.Min(scaleX, scaleY);
}
else
{
scaleX = Math.Max(scaleX, scaleY);
}
scaleY = scaleX;
if (_alignment == SvgPreserveAspectRatioType.XMidYMax ||
_alignment == SvgPreserveAspectRatioType.XMidYMid ||
_alignment == SvgPreserveAspectRatioType.XMidYMin)
{
// align to the Middle X
translateX = (rectToFit.X + rectToFit.Width / 2) - scaleX * (viewBox.X + viewBox.Width / 2);
}
else if (_alignment == SvgPreserveAspectRatioType.XMaxYMax ||
_alignment == SvgPreserveAspectRatioType.XMaxYMid ||
_alignment == SvgPreserveAspectRatioType.XMaxYMin)
{
// align to the right X
translateX = (rectToFit.Width - viewBox.Width * scaleX);
}
if (_alignment == SvgPreserveAspectRatioType.XMaxYMid ||
_alignment == SvgPreserveAspectRatioType.XMidYMid ||
_alignment == SvgPreserveAspectRatioType.XMinYMid)
{
// align to the Middle Y
translateY = (rectToFit.Y + rectToFit.Height / 2) - scaleY * (viewBox.Y + viewBox.Height / 2);
}
else if (_alignment == SvgPreserveAspectRatioType.XMaxYMax ||
_alignment == SvgPreserveAspectRatioType.XMidYMax ||
_alignment == SvgPreserveAspectRatioType.XMinYMax)
{
// align to the bottom Y
translateY = (rectToFit.Height - viewBox.Height * scaleY);
}
}
else
{
translateX = -viewBox.X * scaleX;
translateY = -viewBox.Y * scaleY;
}
}
if (!SvgNumber.IsValid(translateX))
{
translateX = 0;
}
if (!SvgNumber.IsValid(translateY))
{
translateY = 0;
}
if (!SvgNumber.IsValid(scaleX))
{
scaleX = 1;
}
if (!SvgNumber.IsValid(scaleY))
{
scaleY = 1;
}
return(new double[] { translateX, translateY, scaleX, scaleY });
}
