///<summary>
/// Generates the geometry for the sine star
///</summary>
/// <returns>The geometry representing the sine star</returns>
public IGeometry CreateSineStar()
{
Envelope env = Envelope;
double radius = env.Width / 2.0;
double armRatio = ArmLengthRatio;
if (armRatio < 0.0)
{
armRatio = 0.0;
}
if (armRatio > 1.0)
{
armRatio = 1.0;
}
double armMaxLen = armRatio * radius;
double insideRadius = (1 - armRatio) * radius;
double centreX = env.MinX + radius;
double centreY = env.MinY + radius;
Coordinate[] pts = new Coordinate[NumPoints + 1];
int iPt = 0;
for (int i = 0; i < NumPoints; i++)
{
// the fraction of the way thru the current arm - in [0,1]
double ptArcFrac = (i / (double)NumPoints) * NumArms;
double armAngFrac = ptArcFrac - Math.Floor(ptArcFrac);
// the angle for the current arm - in [0,2Pi]
// (each arm is a complete sine wave cycle)
double armAng = 2 * Math.PI * armAngFrac;
// the current length of the arm
double armLenFrac = (Math.Cos(armAng) + 1.0) / 2.0;
// the current radius of the curve (core + arm)
double curveRadius = insideRadius + armMaxLen * armLenFrac;
// the current angle of the curve
double ang = i * (2 * Math.PI / NumPoints);
double x = curveRadius * Math.Cos(ang) + centreX;
double y = curveRadius * Math.Sin(ang) + centreY;
pts[iPt++] = CreateCoord(x, y);
}
pts[iPt] = new Coordinate(pts[0]);
ILinearRing ring = GeomFact.CreateLinearRing(pts);
IPolygon poly = GeomFact.CreatePolygon(ring);
return(poly);
}
public void run()
{
var env = new Envelope(0, 100, 0, 100);
var comb1 = Comb(env, SIZE);
var centre = env.Centre;
var trans = AffineTransformation.RotationInstance(0.5 * Math.PI, centre.X, centre.Y);
var comb2 = (IPolygon)trans.Transform(comb1);
var mp = GeomFact.CreateMultiPolygon(new[] { comb1, comb2 });
//System.out.println(mp);
var isValid = mp.IsValid;
Debug.WriteLine("Is Valid = " + isValid);
}
