/*
* INTERSECT: (LCurve, LCurve)
* - both curves are supposed to be NON-DEGENERATED
*/
public static bool IntersectLL(LCurve lrsA, LCurve lrsB,
out InfoInters inters)
{
inters = null;
if ((lrsA.IsDegen) || (lrsB.IsDegen))
{
throw new ExceptionGMath("Intersect", "IntersectLL(lrs,lrs)", null);
}
VecD a0 = lrsA.Start;
VecD a1 = lrsA.End;
VecD b0 = lrsB.Start;
VecD b1 = lrsB.End;
VecD dirA = lrsA.DirTang;
VecD dirB = lrsB.DirTang;
double det = dirA.Cross(dirB);
// lrsA and lrsB are not parallel
if (Math.Abs(det) > MConsts.EPS_DEC)
{
double lenA = (a1 - a0).Norm;
double lenB = (b1 - b0).Norm;
VecD diff = b0 - a0;
Param parA = (diff.Cross(dirB)) / (det * lenA);
Param parB = (diff.Cross(dirA)) / (det * lenB);
if (lrsA.IsEvaluableStrict(parA) && lrsB.IsEvaluableStrict(parB))
{
VecD pnt = 0.5 * (lrsA.Evaluate(parA) + lrsB.Evaluate(parB));
inters = new IntersD0(parA, parB, pnt, false);
}
return(true);
}
// lrsA and lrsB are parallel
LineD lineB = new LineD(lrsB);
Param paramBInvA0, paramBInvA1;
VecD pntProjA0, pntProjA1;
a0.Project(lineB, out paramBInvA0, out pntProjA0);
a1.Project(lineB, out paramBInvA1, out pntProjA1);
double distA0 = a0.Dist(pntProjA0);
double distA1 = a1.Dist(pntProjA1);
if ((distA0 < MConsts.EPS_DEC) || (distA1 < MConsts.EPS_DEC))
{
// lrsA and lrsB are colinear
Param.TypeParam typeA0 = lrsB.ParamClassify(paramBInvA0);
Param.TypeParam typeA1 = lrsB.ParamClassify(paramBInvA1);
int mult = (int)typeA0 * (int)typeA1;
if (mult == 4)
{
return(true);
}
else if (mult == 1)
{
throw new ExceptionGMath("Intersect", "IntersectLL(lrs,lrs)", null); // lrsA is degenerated
//return false;
}
else if (mult == 2)
{
if ((typeA0 == Param.TypeParam.Start) &&
(typeA1 == Param.TypeParam.Before))
{
inters = new IntersD0(0, 0, a0, false);
}
if ((typeA0 == Param.TypeParam.Before) &&
(typeA1 == Param.TypeParam.Start))
{
inters = new IntersD0(1, 0, a1, false);
}
if ((typeA0 == Param.TypeParam.End) &&
(typeA1 == Param.TypeParam.After))
{
inters = new IntersD0(0, 1, a0, false);
}
if ((typeA0 == Param.TypeParam.After) &&
(typeA1 == Param.TypeParam.End))
{
inters = new IntersD0(1, 1, a1, false);
}
return(true);
}
else if (mult <= 0)
{
return(Inters.RefineIntersLLD1(lrsA, lrsB, out inters));
}
}
return(true);
}
public bool RayParity(RayD ray, CParam parStartRay,
out MConsts.TypeParity typeParity)
{
/*
* ASSUMPTIONS
* INPUT:
* - (parStartRay==null) is the ray does not start at
* the contour
* RETURN VALUE;
* - (false) in case of real failure;
* (true)+(typeParity==Undef) in unclear cases
*
*/
typeParity = MConsts.TypeParity.Undef;
ListInfoInters linters = new ListInfoInters();
bool isStartIntersFound = false;
for (int pozKnot = 0; pozKnot < this.NumKnot; pozKnot++)
{
BCurve curve = this.CurveByPoz(pozKnot);
if (curve != null)
{
Knot knot = this.KnotByPoz(pozKnot);
int numIntersBefore = linters.Count;
if (!Inters.IntersectBL(curve, ray, linters))
{
linters.ClearDestroy();
return(false);
}
int numIntersAfter = linters.Count;
if (numIntersAfter != numIntersBefore)
{
InfoInters inters;
if ((curve.IsDegen) || (curve.IsSelfInters(out inters)))
{
linters.ClearDestroy();
return(true);
}
}
bool isRayStartOnCurve = ((parStartRay != null) &&
(parStartRay.IndKnot == knot.IndexKnot));
for (int iInters = numIntersBefore; iInters < numIntersAfter; iInters++)
{
InfoInters inters = linters[iInters] as InfoInters;
if (inters.Dim == InfoInters.TypeDim.Dim1)
{
linters.ClearDestroy();
return(true);
}
IntersD0 intersD0 = inters as IntersD0;
double parValCurve = intersD0.Ipi.Par(0).Val;
double parValRay = intersD0.Ipi.Par(1).Val;
if (Math.Abs(parValRay) < MConsts.EPS_DEC)
{
if ((!isRayStartOnCurve) || (isRayStartOnCurve && isStartIntersFound))
{
linters.ClearDestroy();
return(true);
}
isStartIntersFound = true;
}
if ((Math.Abs(parValCurve) < MConsts.EPS_DEC_WEAK) ||
(Math.Abs(1.0 - parValCurve) < MConsts.EPS_DEC_WEAK))
{
linters.ClearDestroy();
return(true);
}
VecD dirTangCurve = curve.DirTang(parValCurve);
VecD dirTangRay = (ray as LCurve).DirTang;
if ((dirTangCurve == null) || (dirTangRay == null))
{
linters.ClearDestroy();
return(true);
}
if (Math.Abs(dirTangRay.Cross(dirTangCurve)) < MConsts.EPS_DEC_WEAK)
{
linters.ClearDestroy();
return(true);
}
}
if ((isRayStartOnCurve) && (!isStartIntersFound))
{
linters.ClearDestroy();
return(true);
}
}
}
int numIntersAll = (isStartIntersFound)? linters.Count - 1: linters.Count;
typeParity = (numIntersAll % 2 == 0)? MConsts.TypeParity.Even: MConsts.TypeParity.Odd;
linters.ClearDestroy();
return(true);
}
