/*
* METHODS
*/
public bool IsSeg(out Param parM)
{
/*
* MEANING: NON_DEGENERATED, PARAMETRIC segment
* (implies, that the Bezier is not
* self-intersecting)
*/
parM = null;
if (this.IsDegen)
{
return(false);
}
if (this.cp[0] == this.cp[2])
{
return(false); // S/I bezier
}
if (this.cp[0] == this.cp[1])
{
parM = new Param(0);
return(true);
}
if (this.cp[1] == this.cp[2])
{
parM = new Param(1);
return(true);
}
SegD seg = new SegD(this.cp[0], this.cp[2]);
LineD line = new LineD(seg);
VecD pnt;
Param par;
this.cp[1].Project(line, out par, out pnt);
if (this.cp[1].Dist(pnt) > MConsts.EPS_DEC)
{
return(false);
}
if (!seg.IsEvaluableStrict(par))
{
return(false);
}
parM = par;
if (Math.Abs(parM.Val - 0.5) < MConsts.EPS_DEC)
{
parM.Val = 0.5;
}
return(true);
}
/*
* METHODS
*/
public bool IsSeg(out Param parM)
{
/*
* MEANING: NON_DEGENERATED, PARAMETRIC segment
* (implies, that the Bezier is not
* self-intersecting)
*/
parM=null;
if (this.IsDegen)
return false;
if (this.cp[0]==this.cp[2])
return false; // S/I bezier
if (this.cp[0]==this.cp[1])
{
parM=new Param(0);
return true;
}
if (this.cp[1]==this.cp[2])
{
parM=new Param(1);
return true;
}
SegD seg=new SegD(this.cp[0], this.cp[2]);
LineD line=new LineD(seg);
VecD pnt;
Param par;
this.cp[1].Project(line,out par,out pnt);
if (this.cp[1].Dist(pnt)>MConsts.EPS_DEC)
return false;
if (!seg.IsEvaluableStrict(par))
return false;
parM=par;
if (Math.Abs(parM.Val-0.5)<MConsts.EPS_DEC)
{
parM.Val=0.5;
}
return true;
}
public static bool AuxIntersectBB(SegD seg, Bez2D bez,
InfoConnect icAB, InfoConnect icBA, ListInfoInters linters)
{
// both seg & bez are irreducable !!!
if (linters == null)
{
throw new ExceptionGMath("Intersect", "AuxIntersectBB(seg,bez)", "Null argument");
}
bool connectAB = ((icAB != null) && (icAB.IsConnect));
bool connectBA = ((icBA != null) && (icBA.IsConnect));
if ((connectBA) && (!connectAB))
{
throw new ExceptionGMath("Intersect", "AuxIntersectBB(seg,bez)", null);
//return false;
}
bool connect = connectAB || connectBA;
if (!connect)
{
int numIntersBefore = linters.Count;
if (!Inters.AuxIntersectBL(bez, seg, linters))
{
return(false);
}
linters.ParamSwap(numIntersBefore);
return(true);
}
// bez and seg are connected, => connectAB=true
Param parM;
if (bez.IsSelfInters(out parM))
{
if (connectBA) // both ends are connected
{
// parM!=Infinity - otherwise the seg is degenerated
double valM = parM.Val;
IntersD1 inters;
if (valM > 1)
{
inters = new IntersD1(0, 1,
1, 1 / (2 * valM - 1), seg, true);
}
else
{
inters = new IntersD1(0, 1,
1, (2 * valM) / (2 * valM - 1), seg, true);
}
linters.Add(inters);
return(true);
}
if (icAB.IsTangent)
{
return(true); // no additional intersections
}
else
{
SegD segSupp = bez.SupportFlat();
InfoInters inters;
if (!Inters.IntersectLL(seg, segSupp, out inters))
{
return(false);
}
if (inters == null)
{
return(true);
}
inters.ParamInvalidateBezSI();
int numIntersBefore = linters.Count;
linters.Add(inters);
/*
* CLEAN END-POINT if the Bezier does not return to it
*/
bool coversBezStart = bez.CoversEndPoint(true);
if (!coversBezStart)
{
linters.CleanEndPointBezSI(bez.Start, numIntersBefore);
}
return(true);
}
}
// bezier is NOT self-intersecting
if (connectBA)
{
return(true); // no additional intersections
}
if (icAB.IsTangent)
{
return(true); // no additional intersections
}
// seg & bez are connected and not-tangent,=>
// at most one additional point of intersection
VecD[] cfSeg, cfBez;
seg.PowerCoeff(out cfSeg);
bez.PowerCoeff(out cfBez);
VecD tang = (seg as LCurve).DirTang;
VecD norm = (seg as LCurve).DirNorm;
// connected but not-tangent: one
double[] rootsBez;
int numRootBez;
Equation.RootsReal(cfBez[2].Dot(norm), cfBez[1].Dot(norm),
out numRootBez, out rootsBez);
if (numRootBez == Equation.NumRootInfinite)
{
throw new ExceptionGMath("Intersect", "AuxIntersectBB(seg,bez)", null);
//return false;
}
if (rootsBez == null)
{
return(true);
}
Param parBez = rootsBez[0];
if (bez.IsEvaluableStrict(parBez))
{
double valBez = parBez.Val;
Param parSeg = 1 + valBez * (cfBez[2].Dot(tang) * valBez + cfBez[1].Dot(tang)) / cfSeg[1].Dot(tang);
if (seg.IsEvaluableStrict(parSeg)) // ??? && (parSeg!=1)
{
IntersD0 inters = new IntersD0(parSeg, parBez,
0.5 * (seg.Evaluate(parSeg) + bez.Evaluate(parBez)), false);
linters.Add(inters);
}
}
return(true);
}
public static bool AuxIntersectBB(SegD seg, Bez2D bez,
InfoConnect icAB, InfoConnect icBA, ListInfoInters linters)
{
// both seg & bez are irreducable !!!
if (linters==null)
{
throw new ExceptionGMath("Intersect","AuxIntersectBB(seg,bez)","Null argument");
}
bool connectAB = ((icAB!=null)&&(icAB.IsConnect));
bool connectBA = ((icBA!=null)&&(icBA.IsConnect));
if ((connectBA)&&(!connectAB))
{
throw new ExceptionGMath("Intersect","AuxIntersectBB(seg,bez)",null);
//return false;
}
bool connect=connectAB||connectBA;
if (!connect)
{
int numIntersBefore=linters.Count;
if (!Inters.AuxIntersectBL(bez,seg,linters))
return false;
linters.ParamSwap(numIntersBefore);
return true;
}
// bez and seg are connected, => connectAB=true
Param parM;
if (bez.IsSelfInters(out parM))
{
if (connectBA) // both ends are connected
{
// parM!=Infinity - otherwise the seg is degenerated
double valM=parM.Val;
IntersD1 inters;
if (valM>1)
{
inters=new IntersD1(0,1,
1,1/(2*valM-1),seg,true);
}
else
{
inters=new IntersD1(0,1,
1,(2*valM)/(2*valM-1),seg,true);
}
linters.Add(inters);
return true;
}
if (icAB.IsTangent)
{
return true; // no additional intersections
}
else
{
SegD segSupp=bez.SupportFlat();
InfoInters inters;
if (!Inters.IntersectLL(seg,segSupp,out inters))
return false;
if (inters==null)
return true;
inters.ParamInvalidateBezSI();
int numIntersBefore=linters.Count;
linters.Add(inters);
/*
* CLEAN END-POINT if the Bezier does not return to it
*/
bool coversBezStart=bez.CoversEndPoint(true);
if (!coversBezStart)
{
linters.CleanEndPointBezSI(bez.Start,numIntersBefore);
}
return true;
}
}
// bezier is NOT self-intersecting
if (connectBA)
return true; // no additional intersections
if (icAB.IsTangent)
return true; // no additional intersections
// seg & bez are connected and not-tangent,=>
// at most one additional point of intersection
VecD[] cfSeg, cfBez;
seg.PowerCoeff(out cfSeg);
bez.PowerCoeff(out cfBez);
VecD tang=(seg as LCurve).DirTang;
VecD norm=(seg as LCurve).DirNorm;
// connected but not-tangent: one
double[] rootsBez;
int numRootBez;
Equation.RootsReal(cfBez[2].Dot(norm),cfBez[1].Dot(norm),
out numRootBez, out rootsBez);
if (numRootBez==Equation.NumRootInfinite)
{
throw new ExceptionGMath("Intersect","AuxIntersectBB(seg,bez)",null);
//return false;
}
if (rootsBez==null)
return true;
Param parBez=rootsBez[0];
if (bez.IsEvaluableStrict(parBez))
{
double valBez=parBez.Val;
Param parSeg=1+valBez*(cfBez[2].Dot(tang)*valBez+cfBez[1].Dot(tang))/cfSeg[1].Dot(tang);
if (seg.IsEvaluableStrict(parSeg)) // ??? && (parSeg!=1)
{
IntersD0 inters=new IntersD0(parSeg,parBez,
0.5*(seg.Evaluate(parSeg)+bez.Evaluate(parBez)),false);
linters.Add(inters);
}
}
return true;
}