private void IntersectEdges(TEdge e1, TEdge e2, IntPoint pt, Protects protects)
{
Contract.Requires(e1 != null);
Contract.Requires(e2 != null);
//e1 will be to the left of e2 BELOW the intersection. Therefore e1 is before
//e2 in AEL except when e1 is being inserted at the intersection point ...
var e1Stops = (Protects.Left & protects) == 0 && e1.NextInLML == null && e1.XTop == pt.X && e1.YTop == pt.Y;
var e2Stops = (Protects.Right & protects) == 0 && e2.NextInLML == null && e2.XTop == pt.X && e2.YTop == pt.Y;
var e1Contributing = e1.OutIdx >= 0;
var e2Contributing = e2.OutIdx >= 0;
//update winding counts...
//assumes that e1 will be to the right of e2 ABOVE the intersection
if (e1.PolyType == e2.PolyType)
{
if (IsEvenOddFillType(e1))
{
var oldE1WindCnt = e1.WindCnt;
e1.WindCnt = e2.WindCnt;
e2.WindCnt = oldE1WindCnt;
}
else
{
if (e1.WindCnt + e2.WindDelta == 0)
e1.WindCnt = -e1.WindCnt;
else
e1.WindCnt += e2.WindDelta;
if (e2.WindCnt - e1.WindDelta == 0)
e2.WindCnt = -e2.WindCnt;
else
e2.WindCnt -= e1.WindDelta;
}
}
else
{
if (!IsEvenOddFillType(e2))
e1.WindCnt2 += e2.WindDelta;
else
e1.WindCnt2 = e1.WindCnt2 == 0 ? 1 : 0;
if (!IsEvenOddFillType(e1))
e2.WindCnt2 -= e1.WindDelta;
else
e2.WindCnt2 = e2.WindCnt2 == 0 ? 1 : 0;
}
PolyFillType e1FillType, e2FillType, e1FillType2, e2FillType2;
if (e1.PolyType == PolyType.Subject)
{
e1FillType = _subjFillType;
e1FillType2 = _clipFillType;
}
else
{
e1FillType = _clipFillType;
e1FillType2 = _subjFillType;
}
if (e2.PolyType == PolyType.Subject)
{
e2FillType = _subjFillType;
e2FillType2 = _clipFillType;
}
else
{
e2FillType = _clipFillType;
e2FillType2 = _subjFillType;
}
int e1Wc, e2Wc;
switch (e1FillType)
{
case PolyFillType.Positive:
e1Wc = e1.WindCnt;
break;
case PolyFillType.Negative:
e1Wc = -e1.WindCnt;
break;
default:
e1Wc = Math.Abs(e1.WindCnt);
break;
}
switch (e2FillType)
{
case PolyFillType.Positive:
e2Wc = e2.WindCnt;
break;
case PolyFillType.Negative:
e2Wc = -e2.WindCnt;
break;
default:
e2Wc = Math.Abs(e2.WindCnt);
break;
}
if (e1Contributing && e2Contributing)
{
if (e1Stops || e2Stops ||
(e1Wc != 0 && e1Wc != 1) || (e2Wc != 0 && e2Wc != 1) ||
(e1.PolyType != e2.PolyType && _clipType != ClipType.Xor))
AddLocalMaxPoly(e1, e2, pt);
else
{
AddOutPt(e1, pt);
AddOutPt(e2, pt);
InternalHelpers.Swap(ref e1.Side, ref e2.Side);
InternalHelpers.Swap(ref e1.OutIdx, ref e2.OutIdx);
}
}
else if (e1Contributing)
{
if (e2Wc == 0 || e2Wc == 1)
{
AddOutPt(e1, pt);
InternalHelpers.Swap(ref e1.Side, ref e2.Side);
InternalHelpers.Swap(ref e1.OutIdx, ref e2.OutIdx);
}
}
else if (e2Contributing)
{
if (e1Wc == 0 || e1Wc == 1)
{
AddOutPt(e2, pt);
InternalHelpers.Swap(ref e1.Side, ref e2.Side);
InternalHelpers.Swap(ref e1.OutIdx, ref e2.OutIdx);
}
}
else if ((e1Wc == 0 || e1Wc == 1) &&
(e2Wc == 0 || e2Wc == 1) && !e1Stops && !e2Stops)
{
//neither edge is currently contributing ...
long e1Wc2, e2Wc2;
switch (e1FillType2)
{
case PolyFillType.Positive:
e1Wc2 = e1.WindCnt2;
break;
case PolyFillType.Negative:
e1Wc2 = -e1.WindCnt2;
break;
default:
e1Wc2 = Math.Abs(e1.WindCnt2);
break;
}
switch (e2FillType2)
{
case PolyFillType.Positive:
e2Wc2 = e2.WindCnt2;
break;
case PolyFillType.Negative:
e2Wc2 = -e2.WindCnt2;
break;
default:
e2Wc2 = Math.Abs(e2.WindCnt2);
break;
}
if (e1.PolyType != e2.PolyType)
AddLocalMinPoly(e1, e2, pt);
else if (e1Wc == 1 && e2Wc == 1)
switch (_clipType)
{
case ClipType.Intersection:
if (e1Wc2 > 0 && e2Wc2 > 0)
AddLocalMinPoly(e1, e2, pt);
break;
case ClipType.Union:
if (e1Wc2 <= 0 && e2Wc2 <= 0)
AddLocalMinPoly(e1, e2, pt);
break;
case ClipType.Difference:
if (((e1.PolyType == PolyType.Clip) && (e1Wc2 > 0) && (e2Wc2 > 0)) ||
((e1.PolyType == PolyType.Subject) && (e1Wc2 <= 0) && (e2Wc2 <= 0)))
AddLocalMinPoly(e1, e2, pt);
break;
case ClipType.Xor:
AddLocalMinPoly(e1, e2, pt);
break;
}
else
InternalHelpers.Swap(ref e1.Side, ref e2.Side);
}
if ((e1Stops != e2Stops) &&
((e1Stops && (e1.OutIdx >= 0)) || (e2Stops && (e2.OutIdx >= 0))))
{
InternalHelpers.Swap(ref e1.Side, ref e2.Side);
InternalHelpers.Swap(ref e1.OutIdx, ref e2.OutIdx);
}
//finally, delete any non-contributing maxima edges ...
if (e1Stops)
DeleteFromAEL(e1);
if (e2Stops)
DeleteFromAEL(e2);
}
//------------------------------------------------------------------------------
private void IntersectEdges(TEdge e1, TEdge e2, IntPoint pt, Protects protects)
{
//e1 will be to the left of e2 BELOW the intersection. Therefore e1 is before
//e2 in AEL except when e1 is being inserted at the intersection point ...
bool e1stops = (Protects.ipLeft & protects) == 0 && e1.nextInLML == null &&
e1.xtop == pt.X && e1.ytop == pt.Y;
bool e2stops = (Protects.ipRight & protects) == 0 && e2.nextInLML == null &&
e2.xtop == pt.X && e2.ytop == pt.Y;
bool e1Contributing = (e1.outIdx >= 0);
bool e2contributing = (e2.outIdx >= 0);
//update winding counts...
//assumes that e1 will be to the right of e2 ABOVE the intersection
if (e1.polyType == e2.polyType)
{
if (IsEvenOddFillType(e1))
{
int oldE1WindCnt = e1.windCnt;
e1.windCnt = e2.windCnt;
e2.windCnt = oldE1WindCnt;
}
else
{
if (e1.windCnt + e2.windDelta == 0) e1.windCnt = -e1.windCnt;
else e1.windCnt += e2.windDelta;
if (e2.windCnt - e1.windDelta == 0) e2.windCnt = -e2.windCnt;
else e2.windCnt -= e1.windDelta;
}
}
else
{
if (!IsEvenOddFillType(e2)) e1.windCnt2 += e2.windDelta;
else e1.windCnt2 = (e1.windCnt2 == 0) ? 1 : 0;
if (!IsEvenOddFillType(e1)) e2.windCnt2 -= e1.windDelta;
else e2.windCnt2 = (e2.windCnt2 == 0) ? 1 : 0;
}
PolyFillType e1FillType, e2FillType, e1FillType2, e2FillType2;
if (e1.polyType == PolyType.ptSubject)
{
e1FillType = m_SubjFillType;
e1FillType2 = m_ClipFillType;
}
else
{
e1FillType = m_ClipFillType;
e1FillType2 = m_SubjFillType;
}
if (e2.polyType == PolyType.ptSubject)
{
e2FillType = m_SubjFillType;
e2FillType2 = m_ClipFillType;
}
else
{
e2FillType = m_ClipFillType;
e2FillType2 = m_SubjFillType;
}
int e1Wc, e2Wc;
switch (e1FillType)
{
case PolyFillType.pftPositive: e1Wc = e1.windCnt; break;
case PolyFillType.pftNegative: e1Wc = -e1.windCnt; break;
default: e1Wc = Math.Abs(e1.windCnt); break;
}
switch (e2FillType)
{
case PolyFillType.pftPositive: e2Wc = e2.windCnt; break;
case PolyFillType.pftNegative: e2Wc = -e2.windCnt; break;
default: e2Wc = Math.Abs(e2.windCnt); break;
}
if (e1Contributing && e2contributing)
{
if ( e1stops || e2stops ||
(e1Wc != 0 && e1Wc != 1) || (e2Wc != 0 && e2Wc != 1) ||
(e1.polyType != e2.polyType && m_ClipType != ClipType.ctXor))
AddLocalMaxPoly(e1, e2, pt);
else
DoBothEdges(e1, e2, pt);
}
else if (e1Contributing)
{
if ((e2Wc == 0 || e2Wc == 1) &&
(m_ClipType != ClipType.ctIntersection ||
e2.polyType == PolyType.ptSubject || (e2.windCnt2 != 0)))
DoEdge1(e1, e2, pt);
}
else if (e2contributing)
{
if ((e1Wc == 0 || e1Wc == 1) &&
(m_ClipType != ClipType.ctIntersection ||
e1.polyType == PolyType.ptSubject || (e1.windCnt2 != 0)))
DoEdge2(e1, e2, pt);
}
else if ( (e1Wc == 0 || e1Wc == 1) &&
(e2Wc == 0 || e2Wc == 1) && !e1stops && !e2stops )
{
//neither edge is currently contributing ...
Int64 e1Wc2, e2Wc2;
switch (e1FillType2)
{
case PolyFillType.pftPositive: e1Wc2 = e1.windCnt2; break;
case PolyFillType.pftNegative: e1Wc2 = -e1.windCnt2; break;
default: e1Wc2 = Math.Abs(e1.windCnt2); break;
}
switch (e2FillType2)
{
case PolyFillType.pftPositive: e2Wc2 = e2.windCnt2; break;
case PolyFillType.pftNegative: e2Wc2 = -e2.windCnt2; break;
default: e2Wc2 = Math.Abs(e2.windCnt2); break;
}
if (e1.polyType != e2.polyType)
AddLocalMinPoly(e1, e2, pt);
else if (e1Wc == 1 && e2Wc == 1)
switch (m_ClipType)
{
case ClipType.ctIntersection:
{
if (e1Wc2 > 0 && e2Wc2 > 0)
AddLocalMinPoly(e1, e2, pt);
break;
}
case ClipType.ctUnion:
{
if (e1Wc2 <= 0 && e2Wc2 <= 0)
AddLocalMinPoly(e1, e2, pt);
break;
}
case ClipType.ctDifference:
{
if (e1.polyType == PolyType.ptClip && e1Wc2 > 0 && e2Wc2 > 0 ||
e1.polyType == PolyType.ptSubject && e1Wc2 <= 0 && e2Wc2 <= 0)
AddLocalMinPoly(e1, e2, pt);
break;
}
case ClipType.ctXor:
{
AddLocalMinPoly(e1, e2, pt);
break;
}
}
else
SwapSides(e1, e2);
}
if ((e1stops != e2stops) &&
((e1stops && (e1.outIdx >= 0)) || (e2stops && (e2.outIdx >= 0))))
{
SwapSides(e1, e2);
SwapPolyIndexes(e1, e2);
}
//finally, delete any non-contributing maxima edges ...
if (e1stops) DeleteFromAEL(e1);
if (e2stops) DeleteFromAEL(e2);
}
//------------------------------------------------------------------------------
private void IntersectEdges(TEdge4 e1, TEdge4 e2, IntPoint pt, Protects protects)
{
//e1 will be to the left of e2 BELOW the intersection. Therefore e1 is before
//e2 in AEL except when e1 is being inserted at the intersection point ...
bool e1stops = (Protects.ipLeft & protects) == 0 && e1.nextInLML == null &&
e1.xtop == pt.X && e1.ytop == pt.Y;
bool e2stops = (Protects.ipRight & protects) == 0 && e2.nextInLML == null &&
e2.xtop == pt.X && e2.ytop == pt.Y;
bool e1Contributing = (e1.outIdx >= 0);
bool e2contributing = (e2.outIdx >= 0);
//update winding counts...
//assumes that e1 will be to the right of e2 ABOVE the intersection
if (e1.polyType == e2.polyType)
{
if (IsNonZeroFillType(e1))
{
if (e1.windCnt + e2.windDelta == 0) e1.windCnt = -e1.windCnt;
else e1.windCnt += e2.windDelta;
if (e2.windCnt - e1.windDelta == 0) e2.windCnt = -e2.windCnt;
else e2.windCnt -= e1.windDelta;
}
else
{
int oldE1WindCnt = e1.windCnt;
e1.windCnt = e2.windCnt;
e2.windCnt = oldE1WindCnt;
}
}
else
{
if (IsNonZeroFillType(e2)) e1.windCnt2 += e2.windDelta;
else e1.windCnt2 = (e1.windCnt2 == 0) ? 1 : 0;
if (IsNonZeroFillType(e1)) e2.windCnt2 -= e1.windDelta;
else e2.windCnt2 = (e2.windCnt2 == 0) ? 1 : 0;
}
if (e1Contributing && e2contributing)
{
if (e1stops || e2stops || Math.Abs(e1.windCnt) > 1 ||
Math.Abs(e2.windCnt) > 1 ||
(e1.polyType != e2.polyType && m_ClipType != ClipType.ctXor))
AddLocalMaxPoly(e1, e2, pt);
else
DoBothEdges(e1, e2, pt);
}
else if (e1Contributing)
{
if (m_ClipType == ClipType.ctIntersection)
{
if ((e2.polyType == PolyType.ptSubject || e2.windCnt2 != 0) &&
Math.Abs(e2.windCnt) < 2)
DoEdge1(e1, e2, pt);
}
else
{
if (Math.Abs(e2.windCnt) < 2)
DoEdge1(e1, e2, pt);
}
}
else if (e2contributing)
{
if (m_ClipType == ClipType.ctIntersection)
{
if ((e1.polyType == PolyType.ptSubject || e1.windCnt2 != 0) &&
Math.Abs(e1.windCnt) < 2) DoEdge2(e1, e2, pt);
}
else
{
if (Math.Abs(e1.windCnt) < 2)
DoEdge2(e1, e2, pt);
}
}
else if (Math.Abs(e1.windCnt) < 2 && Math.Abs(e2.windCnt) < 2)
{
//neither edge is currently contributing ...
if (e1.polyType != e2.polyType && !e1stops && !e2stops &&
Math.Abs(e1.windCnt) < 2 && Math.Abs(e2.windCnt) < 2)
AddLocalMinPoly(e1, e2, pt);
else if (Math.Abs(e1.windCnt) == 1 && Math.Abs(e2.windCnt) == 1)
switch (m_ClipType)
{
case ClipType.ctIntersection:
{
if (Math.Abs(e1.windCnt2) > 0 && Math.Abs(e2.windCnt2) > 0)
AddLocalMinPoly(e1, e2, pt);
break;
}
case ClipType.ctUnion:
{
if (e1.windCnt2 == 0 && e2.windCnt2 == 0)
AddLocalMinPoly(e1, e2, pt);
break;
}
case ClipType.ctDifference:
{
if ((e1.polyType == PolyType.ptClip && e2.polyType == PolyType.ptClip &&
e1.windCnt2 != 0 && e2.windCnt2 != 0) ||
(e1.polyType == PolyType.ptSubject && e2.polyType == PolyType.ptSubject &&
e1.windCnt2 == 0 && e2.windCnt2 == 0))
AddLocalMinPoly(e1, e2, pt);
break;
}
case ClipType.ctXor:
{
AddLocalMinPoly(e1, e2, pt);
break;
}
}
else if (Math.Abs(e1.windCnt) < 2 && Math.Abs(e2.windCnt) < 2)
SwapSides(e1, e2);
}
if ((e1stops != e2stops) &&
((e1stops && (e1.outIdx >= 0)) || (e2stops && (e2.outIdx >= 0))))
{
SwapSides(e1, e2);
SwapPolyIndexes(e1, e2);
}
//finally, delete any non-contributing maxima edges ...
if (e1stops) DeleteFromAEL(e1);
if (e2stops) DeleteFromAEL(e2);
}
