override public void ComputeKeys()
{
double eps = 0.001;
double eps2 = eps * eps;
int ib = 0;
int ie = this.NumOfPoints - 1;
SHomog line = new SHomog(Points[ib], Points[ie]);
double lensq = Points[ib].SqrDist(Points[ie]);
if (lensq < eps2)
{
throw new Exception("start and end points are too close");
}
//ie--;
AddBuildStep(null, null, ib, ie, eBuildStep.Build);
Build();
//AddBuildStep(ib, ib, eBuildStep.OutputVertex);
AddBuildStep(null, null, ib, ib, eBuildStep.ReturnKey);
ReturnKey();
//AddBuildStep(null, null, 0, 0, eBuildStep.OutputVertex);
//OutputVertex();
//AddBuildStep(null, null, 0, 0, eBuildStep.OutputVertex);
//AddBuildStep(ib, ib, eBuildStep.OutputVertex);
AddBuildStep(null, null, ib, ie, eBuildStep.DP);
while (m_stack.Count() > 0)
{
switch (m_stack.First().eBuild)
{
case eBuildStep.DP:
DP();
break;
case eBuildStep.Build:
Build();
break;
case eBuildStep.ReturnKey:
ReturnKey();
break;
case eBuildStep.OutputVertex:
//OutputVertex();
Debug.Assert(false);
break;
case eBuildStep.UpdateHull:
UpdateHull();
break;
default:
Debug.Assert(false);
break;
}
}
}
private void DP()
{
double rd = 0, ld = 0, lensq = 0;
int re = 0, le = 0;
Debug.Assert(m_stack.Count() > 0);
Debug.Assert(m_stack.First().eBuild == eBuildStep.DP);
int ib = m_stack.First().iB;
int ie = m_stack.First().iE;
m_stack.Pop();
SHomog line = new SHomog(Points[ib], Points[ie]);
lensq = Points[ib].SqrDist(Points[ie]);
if ((ie - ib) < 2)
{
AddBuildStep(null, null, ie, ie, eBuildStep.ReturnKey);
return;
}
this.m_LHull.Find_Extreme(line, ref le, ref ld);
this.m_RHull.Find_Extreme(line, ref re, ref rd);
if (ld > rd)
{
if (ld * ld > Tol * lensq)
{
PathHullStack lh = m_LHull.Copy();
PathHullStack rh = m_RHull.Copy();
lh.Split(le);
//AddBuildStep(null, null, 0, 0, eBuildStep.OutputVertex);
AddBuildStep(null, null, le, ie, eBuildStep.DP);
AddBuildStep(lh, rh, m_PHTag, 0, eBuildStep.UpdateHull);
AddBuildStep(null, null, ib, le, eBuildStep.DP);
AddBuildStep(null, null, ib, le, eBuildStep.Build);
//AddBuildStep(null, null, le, ie, eBuildStep.DP);
return;
}
else
{
AddBuildStep(null, null, ie, ie, eBuildStep.ReturnKey);
return;
}
}
else
{
if (rd * rd > Tol * lensq)
{
if (m_PHTag != re)
{
m_RHull.Split(re);
}
AddBuildStep(null, null, re, ie, eBuildStep.DP);
AddBuildStep(null, null, re, ie, eBuildStep.Build);
// AddBuildStep(null, null,0, 0, eBuildStep.OutputVertex);
AddBuildStep(null, null, ib, re, eBuildStep.DP);
if (m_PHTag == re)
{
AddBuildStep(null, null, ib, re, eBuildStep.Build);
}
return;
}
else
{
AddBuildStep(null, null, ie, ie, eBuildStep.ReturnKey);
}
}
//if ((ie - ib) < 8) {
// rd = 0;
// for (int i = ib + 1; i < ie; i++) {
// ld = Math.Abs(line.DotProduct_2CH(Points[i]));
// if (ld > rd) {
// rd = ld;
// re = i;
// }
// }
// if (rd * rd > Tol * lensq) {
// AddBuildStep(re, ie, eBuildStep.DP);
// AddBuildStep(ib, re, eBuildStep.OutputVertex);
// AddBuildStep(ib, re, eBuildStep.DP);
// return;
// } else {
// AddBuildStep(ie, ie, eBuildStep.ReturnKey);
// return;
// }
//} else {
//}
}
public void Find_Extreme(SHomog line, ref int ie, ref double dist)
{
int mid, lo, m1, brk, m2, hi;
bool sbase, sbrk;
double d1, d2;
if ((Top - Bot) > 6)
{
lo = Bot;
hi = Top - 1;
sbase = line.Slope_Sign(Pts[Elt[hi]], Pts[Elt[lo]]);
do
{
brk = (lo + hi) / 2;
sbrk = line.Slope_Sign(Pts[Elt[brk]], Pts[Elt[brk + 1]]);
if (sbase == sbrk)
{
if (sbase == line.Slope_Sign(Pts[Elt[lo]], Pts[Elt[brk + 1]]))
{
lo = brk + 1;
}
else
{
hi = brk;
}
}
} while (sbase == sbrk);
m1 = brk;
while (lo < m1)
{
mid = (lo + m1) / 2;
if (sbase == line.Slope_Sign(Pts[Elt[mid]], Pts[Elt[mid + 1]]))
{
lo = mid + 1;
}
else
{
m1 = mid;
}
}
m2 = brk;
while (m2 < hi)
{
mid = (m2 + hi) / 2;
if (sbase == line.Slope_Sign(Pts[Elt[mid]], Pts[Elt[mid + 1]]))
{
hi = mid;
}
else
{
m2 = mid + 1;
}
}
d1 = Math.Abs(line.DotProduct_2CH(Pts[Elt[lo]]));
d2 = Math.Abs(line.DotProduct_2CH(Pts[Elt[m2]]));
if (d1 > d2)
{
dist = d1;
ie = Elt[lo];
}
else
{
dist = d2;
ie = Elt[m2];
}
}
else
{
dist = 0;
for (mid = Bot; mid < Top; mid++)
{
d1 = Math.Abs(line.DotProduct_2CH(Pts[Elt[mid]]));
if (d1 > dist)
{
dist = d1;
ie = Elt[mid];
}
}
}
}
