private static bool IsInRegion(Rect2D region, ILocatable locatable, bool fullyEnclosed)
{
double x0 = locatable.X;
double y0 = locatable.Y;
if (false == fullyEnclosed) // Cross selection.
{
var test = new Rect2D(x0, y0, locatable.Width, locatable.Height);
return region.IntersectsWith(test);
}
double x1 = x0 + locatable.Width;
double y1 = y0 + locatable.Height;
return (region.Contains(x0, y0) && region.Contains(x1, y1));
}