//--------------------------------------------------------------------------------------------------
void _ImportSplineWithFitPoints(DxfDomSpline dxfSpline)
{
// Copy points
var pointCount = dxfSpline.FitPoints.Length;
var points = new TColgp_HArray1OfPnt2d(1, pointCount);
for (int i = 0; i < pointCount; i++)
{
points.SetValue(i + 1, dxfSpline.FitPoints[i]);
}
// Interpolate
var algo = new Geom2dAPI_Interpolate(points, false, 0.001);
if (dxfSpline.HasTangents)
{
algo.Load(dxfSpline.StartTangent, dxfSpline.EndTangent);
}
algo.Perform();
if (!algo.IsDone())
{
Messages.Warning("DxfImporter: Cannot create spline through fit points.");
return;
}
_AddBSplineCurve(algo.Curve());
}
//--------------------------------------------------------------------------------------------------
void _AddBezierSegment(SketchSegmentBezier bezierSegment)
{
if (_Document.Flags.HasFlag(DxfFlags.ExportSplineAsPolygon))
{
var curve = bezierSegment.MakeCurve(_Sketch.Points);
if (curve == null)
{
Messages.Error($"Cannot make curve for converting bezier segment to polyline.");
return;
}
_AddPolygonCurve(curve);
}
else
{
var pointCount = bezierSegment.Points.Length;
var knots = new double[pointCount * 2];
knots.Fill(0, pointCount, 0.0);
knots.Fill(pointCount, pointCount, 1.0);
var points = bezierSegment.Points.Select(idx => _Sketch.Points[idx]).ToArray();
var entity = new DxfDomSpline("0", pointCount - 1, knots, points, null, DxfDomSpline.SplineFlags.None);
_Document.Entities.Add(entity);
}
}
//--------------------------------------------------------------------------------------------------
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);
}
//--------------------------------------------------------------------------------------------------
void _ImportSpline(DxfDomSpline dxfSpline)
{
if (dxfSpline.ControlPoints.Length > 0 && dxfSpline.Knots.Length > 0)
{
_ImportSplineWithControlPoints(dxfSpline);
}
else if (dxfSpline.FitPoints.Length > 0)
{
_ImportSplineWithFitPoints(dxfSpline);
}
}
//--------------------------------------------------------------------------------------------------
void _ImportSplineWithControlPoints(DxfDomSpline dxfSpline)
{
// Copy control points
var poleCount = dxfSpline.ControlPoints.Length;
var poles = new TColgp_Array1OfPnt2d(1, poleCount);
var weights = dxfSpline.Weights != null ? new TColStd_Array1OfReal(1, poleCount) : null;
for (int i = 0; i < poleCount; i++)
{
poles.SetValue(i + 1, dxfSpline.ControlPoints[i]);
weights?.SetValue(i + 1, dxfSpline.Weights[i]);
}
// Count multiplicities and compact knot list
var knotList = new List <double>();
var multList = new List <int>();
var lastKnot = double.NaN;
foreach (var knot in dxfSpline.Knots)
{
if (lastKnot != knot)
{
knotList.Add(knot);
lastKnot = knot;
multList.Add(1);
}
else
{
multList[multList.Count - 1]++;
}
}
// Copy knots and multiplicities
var knotCount = knotList.Count;
var knots = new TColStd_Array1OfReal(1, knotCount);
var mults = new TColStd_Array1OfInteger(1, knotCount);
for (int i = 0; i < knotCount; i++)
{
knots.SetValue(i + 1, knotList[i]);
mults.SetValue(i + 1, multList[i]);
}
// Create spline
var spline = weights != null
? new Geom2d_BSplineCurve(poles, weights, knots, mults, dxfSpline.Degree, dxfSpline.Flags.Has(DxfDomSpline.SplineFlags.IsClosed))
: new Geom2d_BSplineCurve(poles, knots, mults, dxfSpline.Degree, dxfSpline.Flags.Has(DxfDomSpline.SplineFlags.IsClosed));
_AddBSplineCurve(spline);
}
//--------------------------------------------------------------------------------------------------
void _ReadEntities(DxfReader reader)
{
while (reader.GroupCode >= 0)
{
if (reader.GroupCode != 0)
{
reader.Skip();
continue;
}
var type = reader.ReadString()?.ToUpper();
if (type == null)
{
continue;
}
DxfDomEntity entity = null;
switch (type)
{
case "ENDSEC":
return;
case "LINE":
entity = new DxfDomLine();
break;
case "CIRCLE":
case "ARC":
entity = new DxfDomCircle();
break;
case "ELLIPSE":
entity = new DxfDomEllipse();
break;
case "LWPOLYLINE":
entity = new DxfDomLwPolyline();
break;
case "POLYLINE":
entity = new DxfDomPolyline();
break;
case "SPLINE":
entity = new DxfDomSpline();
break;
}
if (entity == null)
{
continue;
}
if (entity.Read(reader))
{
Entities.Add(entity);
}
else
{
Messages.Error($"DxfReader: Incomplete entity description at line {reader.Line}.");
}
}
}