/// <summary>
/// Slicing function used for earthquake puzzles.
/// c should be geodesic (orthogonal to the disk boundary).
/// </summary>
public static void SlicePolygonWithHyperbolicGeodesic(Polygon p, CircleNE c, double thickness, out List <Polygon> output)
{
Geometry g = Geometry.Hyperbolic;
Segment seg = null;
if (c.IsLine)
{
Vector3D p1, p2;
Euclidean2D.IntersectionLineCircle(c.P1, c.P2, new Circle(), out p1, out p2);
seg = Segment.Line(p1, p2);
}
else
{
// Setup the two slicing circles.
// These are cuts equidistant from the passed in geodesic.
Vector3D closestToOrigin = H3Models.Ball.ClosestToOrigin(new Circle3D()
{
Center = c.Center, Radius = c.Radius, Normal = new Vector3D(0, 0, 1)
});
Vector3D p1, p2;
Euclidean2D.IntersectionCircleCircle(c, new Circle(), out p1, out p2);
seg = Segment.Arc(p1, closestToOrigin, p2);
}
Circle c1 = H3Models.Ball.EquidistantOffset(g, seg, thickness / 2);
Circle c2 = H3Models.Ball.EquidistantOffset(g, seg, -thickness / 2);
CircleNE c1NE = c.Clone(), c2NE = c.Clone();
c1NE.Center = c1.Center; c2NE.Center = c2.Center;
c1NE.Radius = c1.Radius; c2NE.Radius = c2.Radius;
SlicePolygonHelper(p, c1NE, c2NE, 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)
{
// 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>
/// Setup a circle we'll use to color neighbors.
/// </summary>
private void SetupNeighborCircle(Tile templateTriangle)
{
Polygon poly = m_tiles.First().Boundary; // Tetrahedral tiling.
CircleNE circ = new CircleNE();
circ.Radius = m_shrink;
circ.Reflect(poly.Segments[2]);
circ.Reflect(templateTriangle.Boundary.Segments[1]);
Mobius m = new Mobius();
m.Isometry(Geometry.Spherical, 0, -circ.CenterNE);
circ.Transform(m);
m_neighborCircle = new CircleNE();
m_neighborCircle.Radius = 1.0 / circ.Radius;
m_originalNeighborCircle = m_neighborCircle.Clone();
System.Func <Vector3D, Vector3D> pointTransform = v =>
{
v *= m_neighborCircle.Radius;
v = new Vector3D(v.Y, v.X);
v.RotateXY(-Math.PI / 2);
return(v);
};
m_neighborToStandardDisk = CalcMobius(pointTransform);
}
/// <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);
}
}
}
