/// <summary>
/// Calculates 3d points on a curve where the linear distance between the points is equal.
/// </summary>
/// <param name="distance">The distance betwen division points.</param>
/// <returns>An array of equidistant points, or null on error.</returns>
public Point3d[] DivideEquidistant(double distance)
{
Point3d[] rc = null;
SimpleArrayPoint3d points = new SimpleArrayPoint3d();
IntPtr pConstThis = ConstPointer();
IntPtr pPoints = points.NonConstPointer();
if (UnsafeNativeMethods.RHC_RhinoDivideCurveEquidistant(pConstThis, distance, pPoints) > 0)
rc = points.ToArray();
points.Dispose();
return rc;
}
/// <summary>
/// Divide the curve into a number of equal-length segments.
/// </summary>
/// <param name="segmentCount">Segment count. Note that the number of division points may differ from the segment count.</param>
/// <param name="includeEnds">If true, then the points at the start and end of the curve are included.</param>
/// <param name="points">A list of division points. If the function returns successfully, this point-array will be filled in.</param>
/// <returns>Array containing division curve parameters on success, null on failure.</returns>
public double[] DivideByCount(int segmentCount, bool includeEnds, out Point3d[] points)
{
points = null;
if (segmentCount < 1)
return null;
int tcount = segmentCount - 1;
if (IsClosed && includeEnds)
tcount = segmentCount;
else if (includeEnds)
tcount = segmentCount + 1;
double[] rc = new double[tcount];
IntPtr curve_ptr = ConstPointer();
SimpleArrayPoint3d outputPoints = new SimpleArrayPoint3d();
IntPtr outputPointsPtr = outputPoints.NonConstPointer();
bool success = UnsafeNativeMethods.RHC_RhinoDivideCurve2(curve_ptr, segmentCount, includeEnds, tcount, outputPointsPtr, ref rc[0]);
if (success)
points = outputPoints.ToArray();
outputPoints.Dispose();
return success ? rc : null;
}
/// <summary>
/// Several types of Curve can have the form of a polyline
/// including a degree 1 NurbsCurve, a PolylineCurve,
/// and a PolyCurve all of whose segments are some form of
/// polyline. IsPolyline tests a curve to see if it can be
/// represented as a polyline.
/// </summary>
/// <param name="polyline">
/// If true is returned, then the polyline form is returned here.
/// </param>
/// <param name="parameters">
/// if true is returned, then the parameters of the polyline
/// points are returned here.
/// </param>
/// <returns>true if this curve can be represented as a polyline; otherwise, false.</returns>
public bool TryGetPolyline(out Polyline polyline, out double[] parameters)
{
polyline = null;
parameters = null;
SimpleArrayPoint3d outputPts = new SimpleArrayPoint3d();
int pointCount = 0;
IntPtr pCurve = ConstPointer();
IntPtr outputPointsPointer = outputPts.NonConstPointer();
Rhino.Runtime.InteropWrappers.SimpleArrayDouble tparams = new SimpleArrayDouble();
IntPtr ptparams = tparams.NonConstPointer();
UnsafeNativeMethods.ON_Curve_IsPolyline2(pCurve, outputPointsPointer, ref pointCount, ptparams);
if (pointCount > 0)
{
polyline = Polyline.PolyLineFromNativeArray(outputPts);
parameters = tparams.ToArray();
}
tparams.Dispose();
outputPts.Dispose();
return (pointCount != 0);
}
/// <summary>
/// Evaluate the derivatives at the specified curve parameter.
/// </summary>
/// <param name="t">Curve parameter to evaluate.</param>
/// <param name="derivativeCount">Number of derivatives to evaluate, must be at least 0.</param>
/// <param name="side">Side of parameter to evaluate. If the parameter is at a kink,
/// it makes a big difference whether the evaluation is from below or above.</param>
/// <returns>An array of vectors that represents all the derivatives starting at zero.</returns>
public Vector3d[] DerivativeAt(double t, int derivativeCount, CurveEvaluationSide side)
{
if (derivativeCount < 0) { throw new InvalidOperationException("The derivativeCount must be larger than or equal to zero"); }
Vector3d[] rc = null;
SimpleArrayPoint3d points = new SimpleArrayPoint3d();
IntPtr pPoints = points.NonConstPointer();
if (UnsafeNativeMethods.ON_Curve_Evaluate(ConstPointer(), derivativeCount, (int)side, t, pPoints))
{
Point3d[] pts = points.ToArray();
rc = new Vector3d[pts.Length];
for (int i = 0; i < pts.Length; i++)
{
rc[i] = new Vector3d(pts[i]);
}
}
points.Dispose();
return rc;
}
/// <summary>
/// Several types of Curve can have the form of a polyline
/// including a degree 1 NurbsCurve, a PolylineCurve,
/// and a PolyCurve all of whose segments are some form of
/// polyline. IsPolyline tests a curve to see if it can be
/// represented as a polyline.
/// </summary>
/// <param name="polyline">
/// If true is returned, then the polyline form is returned here.
/// </param>
/// <returns>true if this curve can be represented as a polyline; otherwise, false.</returns>
public bool TryGetPolyline(out Polyline polyline)
{
polyline = null;
SimpleArrayPoint3d outputPts = new SimpleArrayPoint3d();
int pointCount = 0;
IntPtr pCurve = ConstPointer();
IntPtr outputPointsPointer = outputPts.NonConstPointer();
UnsafeNativeMethods.ON_Curve_IsPolyline2(pCurve, outputPointsPointer, ref pointCount, IntPtr.Zero);
if (pointCount > 0)
{
polyline = Polyline.PolyLineFromNativeArray(outputPts);
}
outputPts.Dispose();
return (pointCount != 0);
}