public void It_Refines_The_Curve_Knot(double val, int insertion)
{
// Arrange
int degree = 3;
List <double> newKnots = new List <double>();
for (int i = 0; i < insertion; i++)
{
newKnots.Add(val);
}
List <Point3> pts = new List <Point3>();
for (int i = 0; i <= 12 - degree - 2; i++)
{
pts.Add(new Point3(i, 0.0, 0.0));
}
NurbsCurve curve = new NurbsCurve(pts, degree);
// Act
NurbsBase curveAfterRefine = KnotVector.Refine(curve, newKnots);
Point3 p0 = curve.PointAt(2.5);
Point3 p1 = curveAfterRefine.PointAt(2.5);
// Assert
(curve.Knots.Count + insertion).Should().Be(curveAfterRefine.Knots.Count);
(pts.Count + insertion).Should().Be(curveAfterRefine.ControlPointLocations.Count);
(p0 == p1).Should().BeTrue();
}
public void It_Refines_The_Surface_In_The_V_Direction(double val, int insertion)
{
// Arrange
List <double> newKnots = new List <double>();
for (int i = 0; i < insertion; i++)
{
newKnots.Add(val);
}
NurbsSurface surface = NurbsSurfaceCollection.Loft();
// Act
NurbsSurface surfaceAfterRefine = KnotVector.Refine(surface, newKnots, SurfaceDirection.V);
Point3 p0 = surface.PointAt(0.5, 0.25);
Point3 p1 = surfaceAfterRefine.PointAt(0.5, 0.25);
// Assert
(surface.KnotsV.Count + insertion).Should().Be(surfaceAfterRefine.KnotsV.Count);
(surface.ControlPointLocations[0].Count + insertion).Should().Be(surfaceAfterRefine.ControlPointLocations[0].Count);
(p0 == p1).Should().BeTrue();
}
/// <summary>
/// Splits (divides) the surface into two parts at the specified parameter
/// </summary>
/// <param name="surface">The NURBS surface to split.</param>
/// <param name="parameter">The parameter at which to split the surface, parameter should be between 0 and 1.</param>
/// <param name="direction">Where to split in the U or V direction of the surface.</param>
/// <returns>If the surface is split vertically (U direction) the left side is returned as the first surface and the right side is returned as the second surface.<br/>
/// If the surface is split horizontally (V direction) the bottom side is returned as the first surface and the top side is returned as the second surface.<br/>
/// If the spit direction selected is both, the split computes first a U direction split and on the result a V direction split.</returns>
internal static NurbsSurface[] Split(NurbsSurface surface, double parameter, SplitDirection direction)
{
KnotVector knots = surface.KnotsV;
int degree = surface.DegreeV;
List <List <Point4> > srfCtrlPts = surface.ControlPoints;
if (direction != SplitDirection.V)
{
srfCtrlPts = CollectionHelpers.Transpose2DArray(surface.ControlPoints);
knots = surface.KnotsU;
degree = surface.DegreeU;
}
List <double> knotsToInsert = CollectionHelpers.RepeatData(parameter, degree + 1);
int span = knots.Span(degree, parameter);
List <List <Point4> > surfPtsLeft = new List <List <Point4> >();
List <List <Point4> > surfPtsRight = new List <List <Point4> >();
NurbsBase result = null;
foreach (List <Point4> pts in srfCtrlPts)
{
NurbsCurve tempCurve = new NurbsCurve(degree, knots, pts);
result = KnotVector.Refine(tempCurve, knotsToInsert);
surfPtsLeft.Add(result.ControlPoints.GetRange(0, span + 1));
surfPtsRight.Add(result.ControlPoints.GetRange(span + 1, span + 1));
}
if (result == null)
{
throw new Exception($"Could not split {nameof(surface)}.");
}
KnotVector knotLeft = result.Knots.GetRange(0, span + degree + 2).ToKnot();
KnotVector knotRight = result.Knots.GetRange(span + 1, span + degree + 2).ToKnot();
NurbsSurface[] surfaceResult = Array.Empty <NurbsSurface>();
switch (direction)
{
case SplitDirection.U:
{
surfaceResult = new NurbsSurface[]
{
new NurbsSurface(degree, surface.DegreeV, knotLeft, surface.KnotsV.Copy(), CollectionHelpers.Transpose2DArray(surfPtsLeft)),
new NurbsSurface(degree, surface.DegreeV, knotRight, surface.KnotsV.Copy(), CollectionHelpers.Transpose2DArray(surfPtsRight))
};
break;
}
case SplitDirection.V:
{
surfaceResult = new NurbsSurface[]
{
new NurbsSurface(surface.DegreeU, degree, surface.KnotsU.Copy(), knotLeft, surfPtsLeft),
new NurbsSurface(surface.DegreeU, degree, surface.KnotsU.Copy(), knotRight, surfPtsRight)
};
break;
}
case SplitDirection.Both:
{
NurbsSurface srf1 = new NurbsSurface(degree, surface.DegreeV, knotLeft, surface.KnotsV.Copy(), CollectionHelpers.Transpose2DArray(surfPtsLeft));
NurbsSurface srf2 = new NurbsSurface(degree, surface.DegreeV, knotRight, surface.KnotsV.Copy(), CollectionHelpers.Transpose2DArray(surfPtsRight));
NurbsSurface[] split1 = Split(srf1, parameter, SplitDirection.V);
NurbsSurface[] split2 = Split(srf2, parameter, SplitDirection.V);
surfaceResult = split2.Concat(split1).ToArray();
break;
}
}
return(surfaceResult);
}
