/// <devdoc>
/// Creates a WindowsRegion from a System.Drawing.Region.
/// </devdoc>
public static WindowsRegion FromRegion(Region region, Graphics g)
{
if (region.IsInfinite(g))
{
// An infinite region would cover the entire device region which is the same as
// not having a clipping region. Observe that this is not the same as having an
// empty region, which when clipping to it has the effect of excluding the entire
// device region.
// To remove the clip region from a dc the SelectClipRgn() function needs to be
// called with a null region ptr - that's why we use the empty constructor here.
// GDI+ will return IntPtr.Zero for Region.GetHrgn(Graphics) when the region is
// Infinite.
return(new WindowsRegion());
}
return(WindowsRegion.FromHregion(region.GetHrgn(g), true));
}