public virtual void TestEllipseNotSweepNotLarge()
{
EllipticalCurveTo.EllipseArc arc = EllipticalCurveTo.EllipseArc.GetEllipse(new Point(0, 0), new Point(20,
0), 30, 10, false, false);
AssertPointEqual(new Point(-20, -19.428090), arc.ll);
AssertPointEqual(new Point(40, 0.5719095), arc.ur);
NUnit.Framework.Assert.AreEqual(38.942441, arc.extent, DELTA);
NUnit.Framework.Assert.AreEqual(70.528779, arc.startAng, DELTA);
}
public virtual void TestCircleNotSweepNotLarge()
{
EllipticalCurveTo.EllipseArc arc = EllipticalCurveTo.EllipseArc.GetEllipse(new Point(0, 0), new Point(20,
0), 10, 10, false, false);
AssertPointEqual(new Point(0, -10), arc.ll);
AssertPointEqual(new Point(20, 10), arc.ur);
NUnit.Framework.Assert.AreEqual(180, arc.extent, DELTA);
NUnit.Framework.Assert.AreEqual(0, arc.startAng, DELTA);
}
public virtual void TestEllipseNotSweepLarge()
{
EllipticalCurveTo.EllipseArc arc = EllipticalCurveTo.EllipseArc.GetEllipse(new Point(0, 0), new Point(20,
0), 30, 10, false, true);
AssertPointEqual(new Point(-20, -0.571909), arc.ll);
AssertPointEqual(new Point(40, 19.428090), arc.ur);
NUnit.Framework.Assert.AreEqual(321.057558, arc.extent, DELTA);
NUnit.Framework.Assert.AreEqual(289.4712206344907, arc.startAng, DELTA);
}
){kind=link}
internal static EllipticalCurveTo.EllipseArc GetEllipse(Point start, Point end, double a, double b, bool sweep
, bool largeArc)
{
double r1 = (start.x - end.x) / (-2.0 * a);
double r2 = (start.y - end.y) / (2.0 * b);
double factor = Math.Sqrt(r1 * r1 + r2 * r2);
if (factor > 1)
{
/* If rx, ry and φ are such that there is no solution (basically, the ellipse is not big enough
* to reach from (x1, y1) to (x2, y2)) then the ellipse's semi-axes are scaled up uniformly
* until there is exactly one solution (until the ellipse is just big enough).
*/
return(GetEllipse(start, end, a * factor, b * factor, sweep, largeArc));
}
double between1 = Math.Atan(r1 / r2);
double between2 = Math.Asin(factor);
EllipticalCurveTo.EllipseArc result = CalculatePossibleMiddle(start, end, a, b, between1 + between2, sweep
, largeArc);
if (result != null)
{
return(result);
}
result = CalculatePossibleMiddle(start, end, a, b, Math.PI + between1 - between2, sweep, largeArc);
if (result != null)
{
return(result);
}
result = CalculatePossibleMiddle(start, end, a, b, Math.PI + between1 + between2, sweep, largeArc);
if (result != null)
{
return(result);
}
result = CalculatePossibleMiddle(start, end, a, b, between1 - between2, sweep, largeArc);
if (result != null)
{
return(result);
}
throw new SvgProcessingException(SvgExceptionMessageConstant.COULD_NOT_DETERMINE_MIDDLE_POINT_OF_ELLIPTICAL_ARC
);
}