public BCurve SubCurve(Param parA, Param parB)
{
if ((!this.IsEvaluableStrict(parA)) || (!this.IsEvaluableStrict(parB)))
{
return(null);
}
Bez2D bezWork = new Bez2D(this);
double valA = parA.Val;
double valB = parB.Val;
if (valA > valB)
{
bezWork.Reverse();
valA = 1 - valA;
valB = 1 - valB;
}
/*
* if ((valS==0)&&(valE==1))
* return new Bez2D(bezWork);
* CurveD curveS, curveE;
* if (valS==0)
* {
* bezWork.Subdivide(valB,out curveS, out curveE);
* return curveS;
* }
* if (valE==1)
* {
* bezWork.Subdivide(valA,out curveS, out curveE);
* return curveE;
* }
*/
VecD a01, a12, b01, b12;
a01 = (1 - valA) * bezWork.Cp(0) + valA * bezWork.Cp(1);
a12 = (1 - valA) * bezWork.Cp(1) + valA * bezWork.Cp(2);
b01 = (1 - valB) * bezWork.Cp(0) + valB * bezWork.Cp(1);
b12 = (1 - valB) * bezWork.Cp(1) + valB * bezWork.Cp(2);
VecD start, mid, end;
start = (1 - valA) * a01 + valA * a12;
end = (1 - valB) * b01 + valB * b12;
mid = (1 - valB) * a01 + valB * a12;
// mid=(1-valA)*(1-valB)*bezWork.Cp(0)+valA*valB*bezWork.Cp(2)+
// ((1-valB)*valA+(1-valA)*valB))*bezWork.Cp(1);
return(new Bez2D(start, mid, end));
}
public bool ProjectGeneral(Bez2D bez, out Param[] pars, out VecD pnt)
{
/*
* MEANING: parameter (or parameters) of the nearest point
* in range [0,1]
*
* ASSUMPTIONS: bezier can be non-reduced
* bezier can be self-intersecting
*
*/
pars=null;
pnt=null;
Param parM;
if (!bez.IsSelfInters(out parM))
{
Param par;
if (!this.Project(bez,out par,out pnt))
return false;
if (par!=null)
{
pars=new Param[1];
pars[0]=par;
}
return true;
}
double valM=parM.Val;
if (parM<0)
{
Bez2D bezRev=new Bez2D(bez);
bezRev.Reverse();
if (!this.ProjectGeneral(bezRev,out pars,out pnt))
return false;
if (pars!=null)
{
for (int iPar=0; iPar<pars.Length; iPar++)
{
pars[iPar].Reverse(1);
}
}
return true;
}
SegD support=bez.SupportFlat();
Param parSupport;
if (!this.Project(support,out parSupport, out pnt))
return false;
if (!bez.ParamFromSupport(parSupport,out pars))
return false;
return true;
}
public BCurve SubCurve(Param parA, Param parB)
{
if ((!this.IsEvaluableStrict(parA))||(!this.IsEvaluableStrict(parB)))
return null;
Bez2D bezWork=new Bez2D(this);
double valA=parA.Val;
double valB=parB.Val;
if (valA>valB)
{
bezWork.Reverse();
valA=1-valA;
valB=1-valB;
}
/*
if ((valS==0)&&(valE==1))
return new Bez2D(bezWork);
CurveD curveS, curveE;
if (valS==0)
{
bezWork.Subdivide(valB,out curveS, out curveE);
return curveS;
}
if (valE==1)
{
bezWork.Subdivide(valA,out curveS, out curveE);
return curveE;
}
*/
VecD a01,a12,b01,b12;
a01=(1-valA)*bezWork.Cp(0)+valA*bezWork.Cp(1);
a12=(1-valA)*bezWork.Cp(1)+valA*bezWork.Cp(2);
b01=(1-valB)*bezWork.Cp(0)+valB*bezWork.Cp(1);
b12=(1-valB)*bezWork.Cp(1)+valB*bezWork.Cp(2);
VecD start, mid, end;
start=(1-valA)*a01+valA*a12;
end=(1-valB)*b01+valB*b12;
mid=(1-valB)*a01+valB*a12;
// mid=(1-valA)*(1-valB)*bezWork.Cp(0)+valA*valB*bezWork.Cp(2)+
// ((1-valB)*valA+(1-valA)*valB))*bezWork.Cp(1);
return new Bez2D(start,mid,end);
}
public bool ProjectGeneral(Bez2D bez, out Param[] pars, out VecD pnt)
{
/*
* MEANING: parameter (or parameters) of the nearest point
* in range [0,1]
*
* ASSUMPTIONS: bezier can be non-reduced
* bezier can be self-intersecting
*
*/
pars = null;
pnt = null;
Param parM;
if (!bez.IsSelfInters(out parM))
{
Param par;
if (!this.Project(bez, out par, out pnt))
{
return(false);
}
if (par != null)
{
pars = new Param[1];
pars[0] = par;
}
return(true);
}
double valM = parM.Val;
if (parM < 0)
{
Bez2D bezRev = new Bez2D(bez);
bezRev.Reverse();
if (!this.ProjectGeneral(bezRev, out pars, out pnt))
{
return(false);
}
if (pars != null)
{
for (int iPar = 0; iPar < pars.Length; iPar++)
{
pars[iPar].Reverse(1);
}
}
return(true);
}
SegD support = bez.SupportFlat();
Param parSupport;
if (!this.Project(support, out parSupport, out pnt))
{
return(false);
}
if (!bez.ParamFromSupport(parSupport, out pars))
{
return(false);
}
return(true);
}