void ON_GL( const ON_Curve& curve,
GLUnurbsObj* nobj, // created with gluNewNurbsRenderer )
GLenum type, // = 0 (and type is automatically set)
double xform[][4]
)
{
const ON_PolyCurve* poly_curve = ON_PolyCurve::Cast(&curve);
if ( poly_curve )
{
ON_Curve* pSegmentCurve = 0;
int segment_count = poly_curve->Count();
int i;
for ( i = 0; i < segment_count; i++ ) {
pSegmentCurve = poly_curve->SegmentCurve(i);
if ( pSegmentCurve )
ON_GL( *pSegmentCurve, nobj, type, xform );
}
return;
}
const ON_CurveProxy* curve_proxy = ON_CurveProxy::Cast(&curve);
if ( curve_proxy && !curve_proxy->ProxyCurveIsReversed() )
{
const ON_Curve* real_curve = curve_proxy->ProxyCurve();
if ( 0 == real_curve )
return;
if ( curve_proxy == real_curve )
return;
if ( curve_proxy->ProxyCurveDomain() == real_curve->Domain() )
{
ON_GL( *real_curve, nobj, type, xform );
return;
}
}
{
ON_NurbsCurve tmp;
const ON_NurbsCurve* nurbs_curve = ON_NurbsCurve::Cast(&curve);
if ( !nurbs_curve )
{
if ( curve.GetNurbForm(tmp) )
nurbs_curve = &tmp;
}
ON_GL( *nurbs_curve, nobj, type, true, NULL, xform );
}
}
// Add the isocurves of a BrepFace to the partial boundingbox result.
static void ON_Brep_GetTightIsoCurveBoundingBox_Helper( const TL_Brep& tlbrep, const ON_BrepFace& face, ON_BoundingBox& bbox, const ON_Xform* xform, int dir )
{
ON_Interval domain = face.Domain(1 - dir);
int degree = face.Degree(1 - dir);
int spancount = face.SpanCount(1 - dir);
int spansamples = degree * (degree + 1) - 1;
if( spansamples < 2 )
spansamples = 2;
// pbox delineates the extremes of the face interior.
// We can use it to trivially reject spans and isocurves.
ON_BrepLoop* pOuterLoop = face.OuterLoop();
if( NULL==pOuterLoop )
return;
const ON_BoundingBox& pbox = pOuterLoop->m_pbox;
double t0 = ((dir == 0) ? pbox.Min().y : pbox.Min().x);
double t1 = ((dir == 0) ? pbox.Max().y : pbox.Max().x);
// Get the surface span vector.
ON_SimpleArray<double> spanvector(spancount + 1);
spanvector.SetCount(spancount + 1);
face.GetSpanVector(1 - dir, spanvector.Array());
// Generate a list of all the sampling parameters.
ON_SimpleArray<double> samples(spancount * spansamples);
for( int s = 0; s < spancount; s++)
{
double s0 = spanvector[s];
double s1 = spanvector[s+1];
// Reject span if it does not intersect the pbox.
if( s1 < t0 ) { continue; }
if( s0 > t1 ) { continue; }
ON_Interval span(s0, s1);
for( int i = 1; i < spansamples; i++ )
{
double t = span.ParameterAt((double)i / (double)(spansamples - 1));
// Reject iso if it does not intersect the pbox.
if( t < t0 )
continue;
if( t > t1 )
break;
samples.Append(t);
}
}
//Iterate over samples
int sample_count = samples.Count();
ON_BoundingBox loose_box;
ON_SimpleArray<ON_Interval> intervals;
ON_NurbsCurve isosubcrv;
for( int i = 0; i<sample_count; i++)
{
// Retrieve iso-curve.
ON_Curve* isocrv = face.IsoCurve(dir, samples[i]);
while( NULL!=isocrv )
{
// Transform isocurve if necessary, this is better than transforming downstream boundingboxes.
if( xform )
isocrv->Transform(*xform);
// Compute loose box.
if( !isocrv->GetBoundingBox(loose_box, false))
break;
// Determine whether the loose box is already contained within the partial result.
if( bbox.Includes(loose_box, false) )
break;
// Solve trimming domains for the iso-curve.
intervals.SetCount(0);
if( !tlbrep.GetIsoIntervals(face, dir, samples[i], intervals))
break;
// Iterate over trimmed iso-curves.
int interval_count = intervals.Count();
for( int k=0; k<interval_count; k++ )
{
//this to mask a bug in Rhino4. GetNurbForm does not destroy the Curve Tree. It does now.
isosubcrv.DestroyCurveTree();
isocrv->GetNurbForm(isosubcrv, 0.0, &intervals[k]);
ON_Brep_GetTightCurveBoundingBox_Helper(isosubcrv, bbox, NULL, NULL);
}
break;
}
if( isocrv )
{
delete isocrv;
isocrv = NULL;
}
}
}
ON_Surface::ISO
ON_Surface::IsIsoparametric( const ON_Curve& curve, const ON_Interval* subdomain ) const
{
ISO iso = not_iso;
if ( subdomain )
{
ON_Interval cdom = curve.Domain();
double t0 = cdom.NormalizedParameterAt(subdomain->Min());
double t1 = cdom.NormalizedParameterAt(subdomain->Max());
if ( t0 < t1-ON_SQRT_EPSILON )
{
if ( (t0 > ON_SQRT_EPSILON && t0 < 1.0-ON_SQRT_EPSILON) || (t1 > ON_SQRT_EPSILON && t1 < 1.0-ON_SQRT_EPSILON) )
{
cdom.Intersection(*subdomain);
if ( cdom.IsIncreasing() )
{
ON_NurbsCurve nurbs_curve;
if ( curve.GetNurbForm( nurbs_curve, 0.0,&cdom) )
{
return IsIsoparametric( nurbs_curve, 0 );
}
}
}
}
}
ON_BoundingBox bbox;
double tolerance = 0.0;
const int dim = curve.Dimension();
if ( (dim == 2 || dim==3) && curve.GetBoundingBox(bbox) )
{
iso = IsIsoparametric( bbox );
switch (iso) {
case x_iso:
case W_iso:
case E_iso:
// make sure curve is a (nearly) vertical line
// and weed out vertical scribbles
tolerance = bbox.m_max.x - bbox.m_min.x;
if ( tolerance < ON_ZERO_TOLERANCE && ON_ZERO_TOLERANCE*1024.0 <= (bbox.m_max.y-bbox.m_min.y) )
{
// 26 March 2007 Dale Lear
// If tolerance is tiny, then use ON_ZERO_TOLERANCE
// This fixes cases where iso curves where not getting
// the correct flag because tol=1e-16 and the closest
// point to line had calculation errors of 1e-15.
tolerance = ON_ZERO_TOLERANCE;
}
if ( !curve.IsLinear( tolerance ) )
iso = not_iso;
break;
case y_iso:
case S_iso:
case N_iso:
// make sure curve is a (nearly) horizontal line
// and weed out horizontal scribbles
tolerance = bbox.m_max.y - bbox.m_min.y;
if ( tolerance < ON_ZERO_TOLERANCE && ON_ZERO_TOLERANCE*1024.0 <= (bbox.m_max.x-bbox.m_min.x) )
{
// 26 March 2007 Dale Lear
// If tolerance is tiny, then use ON_ZERO_TOLERANCE
// This fixes cases where iso curves where not getting
// the correct flag because tol=1e-16 and the closest
// point to line had calculation errors of 1e-15.
tolerance = ON_ZERO_TOLERANCE;
}
if ( !curve.IsLinear( tolerance ) )
iso = not_iso;
break;
default:
// nothing here
break;
}
}
return iso;
}
