/// <summary>
/// Slices a polygon by a circle with some thickness.
/// Input circle may be a line.
/// </summary>
/// <remarks>The input polygon might get reversed</remarks>
public static void SlicePolygon(Polygon p, CircleNE c, Geometry g, double thickness, out List <Polygon> output)
{
// Setup the two slicing circles.
CircleNE c1 = c.Clone(), c2 = c.Clone();
Mobius m = new Mobius();
Vector3D pointOnCircle = c.IsLine ? c.P1 : c.Center + new Vector3D(c.Radius, 0);
m.Hyperbolic2(g, c1.CenterNE, pointOnCircle, thickness / 2);
c1.Transform(m);
m.Hyperbolic2(g, c2.CenterNE, pointOnCircle, -thickness / 2);
c2.Transform(m);
SlicePolygonHelper(p, c1, c2, out output);
}
/// <summary>
/// Slices a polygon by a circle with some thickness.
/// Input circle may be a line.
/// </summary>
/// <remarks>The input polygon might get reversed</remarks>
public static void SlicePolygon(Polygon p, CircleNE c, Geometry g, double thickness, out List <Polygon> output)
{
output = new List <Polygon>();
// Setup the two slicing circles.
CircleNE c1 = c.Clone(), c2 = c.Clone();
Mobius m = new Mobius();
Vector3D pointOnCircle = c.IsLine ? c.P1 : c.Center + new Vector3D(c.Radius, 0);
m.Hyperbolic2(g, c1.CenterNE, pointOnCircle, thickness / 2);
c1.Transform(m);
m.Hyperbolic2(g, c2.CenterNE, pointOnCircle, -thickness / 2);
c2.Transform(m);
// ZZZ - alter Clip method to work on Polygons and use that.
// Slice it up.
List <Polygon> sliced1, sliced2;
Slicer.SlicePolygon(p, c1, out sliced1);
Slicer.SlicePolygon(p, c2, out sliced2);
// Keep the ones we want.
foreach (Polygon newPoly in sliced1)
{
bool outside = !c1.IsPointInsideNE(newPoly.CentroidApprox);
if (outside)
{
output.Add(newPoly);
}
}
foreach (Polygon newPoly in sliced2)
{
bool inside = c2.IsPointInsideNE(newPoly.CentroidApprox);
if (inside)
{
output.Add(newPoly);
}
}
}
