//--------------------------------------------------------------------------------------------------
void _AddBSplineCurve(Geom2d_BSplineCurve bspline, double first, double last)
{
// Cut spline
bspline = Geom2dConvert.SplitBSplineCurve(bspline, first, last, 0.00001);
if (_Document.Flags.HasFlag(DxfFlags.ExportSplineAsPolygon))
{
_AddPolygonCurve(bspline);
return;
}
if (bspline.Degree() > 3)
{
// Try to reduce the order of the curve
var continuity = bspline.Continuity();
if (continuity != GeomAbs_Shape.GeomAbs_C0)
{
continuity = GeomAbs_Shape.GeomAbs_C1;
}
var converter = new Geom2dConvert_ApproxCurve(bspline, _Precision * 10.0, continuity, 100, 3);
if (!(converter.IsDone() && converter.HasResult()))
{
Messages.Warning("DxfExporter: BSpline curve has an undecreasable degree of " + bspline.Degree() + ".");
return;
}
bspline = converter.Curve();
}
var knotSource = bspline.KnotSequence();
var knots = new double[knotSource.Length()];
int sourceStart = knotSource.Lower();
for (int i = 0; i < knots.Length; i++)
{
knots[i] = knotSource.Value(sourceStart + i);
}
var points = new Pnt2d[bspline.NbPoles()];
var weights = new double[points.Length];
for (int i = 0; i < bspline.NbPoles(); i++)
{
points[i] = bspline.Pole(i + 1);
weights[i] = bspline.Weight(i + 1);
}
var flags = DxfDomSpline.SplineFlags.None;
if (bspline.IsRational())
{
flags = flags.Added(DxfDomSpline.SplineFlags.IsRational);
}
var entity = new DxfDomSpline(_CurrentLayer, bspline.Degree(), knots, points, weights, flags);
_Document.Entities.Add(entity);
}
//--------------------------------------------------------------------------------------------------
public static bool RenderBSplineCurve(IDrawingRenderer renderer, Geom2d_BSplineCurve bspline, double first, double last, bool reverse)
{
if (renderer.Capabilities.BSplineCurveMaxDegree > 0)
{
bspline = Geom2dConvert.SplitBSplineCurve(bspline, first, last, 0.00001);
if (bspline.Degree() > renderer.Capabilities.BSplineCurveMaxDegree)
{
// Try to reduce the order of the curve
var continuity = bspline.Continuity();
if (continuity != GeomAbs_Shape.GeomAbs_C0)
{
continuity = GeomAbs_Shape.GeomAbs_C1;
}
var converter = new Geom2dConvert_ApproxCurve(bspline, 0.0001, continuity, 100, 3);
if (!(converter.IsDone() && converter.HasResult()))
{
Messages.Warning("BrepRenderHelper: BSpline curve has an undecreasable degree of " + bspline.Degree() + ".");
return(false);
}
bspline = converter.Curve();
}
var knotSource = bspline.KnotSequence();
var knots = new double[knotSource.Length()];
int sourceStart = knotSource.Lower();
for (int i = 0; i < knots.Length; i++)
{
knots[i] = knotSource.Value(sourceStart + i);
}
var points = new Pnt2d[bspline.NbPoles()];
var weights = new double[points.Length];
for (int i = 0; i < bspline.NbPoles(); i++)
{
points[i] = bspline.Pole(i + 1);
weights[i] = bspline.Weight(i + 1);
}
renderer.BSplineCurve(bspline.Degree(), knots, points, weights, bspline.IsRational());
return(true);
}
else
{
// Cannot render BSpline, Try bezier
var converter = new Geom2dConvert_BSplineCurveToBezierCurve(bspline, first, last, 0.001 /*Precision.PConfusion() * 10*/);
bool result = true;
if (reverse)
{
for (int i = converter.NbArcs(); i >= 1; i -= 1)
{
var arc = converter.Arc(i);
result &= RenderBezierCurve(renderer, arc, arc.FirstParameter(), arc.LastParameter(), true);
}
}
else
{
for (int i = 1; i <= converter.NbArcs(); i += 1)
{
var arc = converter.Arc(i);
result &= RenderBezierCurve(renderer, arc, arc.FirstParameter(), arc.LastParameter(), false);
}
}
return(result);
}
}