diff --git a/tools/pathops_visualizer.htm b/tools/pathops_visualizer.htm
index 3cf835c..67552a5 100644
--- a/tools/pathops_visualizer.htm
+++ b/tools/pathops_visualizer.htm
@@ -2,6 +2,8 @@
 <head>
 <div height="0" hidden="true">
 
+Skia UnitTests: --match PathOpsSkp$ --resourcePath resources\ SK_DEBUG
+
 <div id="skpwww_gorcraft_ru_1">
 seg=1 {{{{1170, 4559}, {1176, 4559}, {1176, 4565}}}, 0.707106769f}
 seg=2 {{{1176, 4565}, {1176, 4590}}}
@@ -31,41 +33,6 @@
 SkOpSegment::addT insert t=0.972972973 segID=12 spanID=30
 debugShowConicLineIntersection no intersect {{{{84,4596}, {78,4596}, {78,4590}}}, 0.707106769} {{{1171,4595}, {83,4595}}}
 debugShowConicLineIntersection no intersect {{{{83,4595}, {78.0086746,4595}, {78,4590.00586}}}, 0.707720578} {{{78,4590}, {78,4565}}}
-id=1 1=(0,1) [4,2] id=2 2=(0,0.5) [1] 4=(0.5,1) [1]
-id=1 1=(0,0.5) [4,2] 3=(0.5,1) [4] id=2 2=(0,0.5) [1] 4=(0.5,1) [3,1]
-id=1 1=(0,0.5) [2] 3=(0.5,1) [6,4] id=2 2=(0,0.5) [1] 4=(0.5,0.75) [3] 6=(0.75,1) [3]
-id=1 3=(0.5,1) [6,4] id=2 4=(0.5,0.75) [3] 6=(0.75,1) [3]
-id=1 3=(0.5,0.75) [6,4] 5=(0.75,1) [6] id=2 4=(0.5,0.75) [3] 6=(0.75,1) [5,3]
-id=1 3=(0.5,0.75) [4] 5=(0.75,1) [10,6] id=2 4=(0.5,0.75) [3] 6=(0.75,0.875) [5] 10=(0.875,1) [5]
-id=1 5=(0.75,1) [10,6] id=2 6=(0.75,0.875) [5] 10=(0.875,1) [5]
-id=1 5=(0.75,0.875) [10,6] 7=(0.875,1) [10] id=2 6=(0.75,0.875) [5] 10=(0.875,1) [7,5]
-id=1 5=(0.75,0.875) [10] 7=(0.875,1) [10] id=2 10=(0.875,1) [7,5]
-id=1 7=(0.875,1) [16,10] id=2 10=(0.875,0.9375) [7] 16=(0.9375,1) [7]
-id=1 7=(0.875,0.9375) [16,10] 9=(0.9375,1) [16] id=2 10=(0.875,0.9375) [7] 16=(0.9375,1) [9,7]
-id=1 7=(0.875,0.9375) [16] 9=(0.9375,1) [16] id=2 16=(0.9375,1) [9,7]
-id=1 9=(0.9375,1) [20,16] id=2 16=(0.9375,0.96875) [9] 20=(0.96875,1) [9]
-id=1 9=(0.9375,0.96875) [20,16] 11=(0.96875,1) [20] id=2 16=(0.9375,0.96875) [9] 20=(0.96875,1) [11,9]
-id=1 9=(0.9375,0.96875) [20] 11=(0.96875,1) [20] id=2 20=(0.96875,1) [11,9]
-id=1 11=(0.96875,1) [24,20] id=2 20=(0.96875,0.984375) [11] 24=(0.984375,1) [11]
-id=1 11=(0.96875,0.984375) [24,20] 13=(0.984375,1) [24] id=2 20=(0.96875,0.984375) [11] 24=(0.984375,1) [13,11]
-id=1 11=(0.96875,0.984375) [24] 13=(0.984375,1) [24] id=2 24=(0.984375,1) [13,11]
-id=1 13=(0.984375,1) [28,24] id=2 24=(0.984375,0.992188) [13] 28=(0.992188,1) [13]
-id=1 13=(0.984375,0.992188) [24] 15=(0.992188,1) [28] id=2 24=(0.984375,0.992188) [13] 28=(0.992188,1) [15]
-id=1 15=(0.992188,1) [28] id=2 28=(0.992188,1) [15]
-id=1 15=(0.992188,1) [32,28] id=2 28=(0.992188,0.996094) [15] 32=(0.996094,1) [15]
-id=1 15=(0.992188,0.996094) [28] 17=(0.996094,1) [28,32] id=2 28=(0.992188,0.996094) [17,15] 32=(0.996094,1) [17]
-id=1 17=(0.996094,1) [32] id=2 32=(0.996094,1) [17]
-id=1 17=(0.996094,1) [36,32] id=2 32=(0.996094,0.998047) [17] 36=(0.998047,1) [17]
-id=1 19=(0.998047,1) [36] id=2 36=(0.998047,1) [19]
-id=1 19=(0.998047,1) [38,36] id=2 36=(0.998047,0.999023) [19] 38=(0.999023,1) [19]
-setPerp t=0.998046875 cPt=(78.0000229,4590.01658) == oppT=0.998483762 fPerpPt=(78.0000301,4590.01658)
-setPerp t=0.999023438 cPt=(78.0000057,4590.00829) == oppT=0.99965636 fPerpPt=(78.0000048,4590.00829)
-setPerp t=0.999023438 cPt=(78.0000168,4590.01276) == oppT=0.998496341 fPerpPt=(78.0000136,4590.01276)
-setPerp t=0.998046875 cPt=(78.0000229,4590.01658) == oppT=0.998483762 fPerpPt=(78.0000301,4590.01658)
-setPerp t=0.999023438 cPt=(78.0000057,4590.00829) == oppT=0.99965636 fPerpPt=(78.0000048,4590.00829)
-setPerp t=0.999023438 cPt=(78.0000168,4590.01276) == oppT=0.998496341 fPerpPt=(78.0000136,4590.01276)
-setPerp t=0.999339899 cPt=(78.0000103,4590.01053) == oppT=0.998759893 fPerpPt=(78.0000092,4590.01053)
-id=1 21=(0.99934,0.99934) [36] id=2 36=(0.99876,0.99876) [21]
 debugShowConicIntersection wtTs[0]=0.999339899 {{{{83,4595}, {78.0086746,4595}, {78,4590.00586}}}, 0.707720578} {{78.0000076,4590.01074}} wnTs[0]=0.99876 {{{{84,4596}, {78,4596}, {78,4590}}}, 0.707106769}
 SkOpSegment::addT insert t=0.999339899 segID=5 spanID=31
 SkOpSegment::addT insert t=0.998759893 segID=14 spanID=32
@@ -74,34 +41,6 @@
 debugShowConicLineIntersection wtTs[0]=0 {{{{78,4565}, {78,4559}, {84,4559}}}, 0.707106769} {{78,4565}} wnTs[0]=1 {{{78,4590.00586}, {78,4565}}}
 debugShowConicLineIntersection wtTs[0]=1 {{{{84,4596}, {78,4596}, {78,4590}}}, 0.707106769} {{78,4590}} wnTs[0]=0.00023432 {{{78,4590.00586}, {78,4565}}}
 debugShowConicLineIntersection wtTs[0]=0 {{{{78,4565}, {78,4559}, {84,4559}}}, 0.707106769} {{78,4565}} wnTs[0]=1 {{{78,4590}, {78,4565}}}
-id=1 1=(0,1) [4,2] id=2 2=(0,0.5) [1] 4=(0.5,1) [1]
-id=1 1=(0,0.5) [4,2] 3=(0.5,1) [2,4] id=2 2=(0,0.5) [3,1] 4=(0.5,1) [3,1]
-id=1 1=(0,0.5) [6,4,2] 3=(0.5,1) [6,4] id=2 2=(0,0.25) [1] 6=(0.25,0.5) [1,3] 4=(0.5,1) [3,1]
-id=1 1=(0,0.25) [6,2] 5=(0.25,0.5) [2,4,6] 3=(0.5,1) [6,4] id=2 2=(0,0.25) [5,1] 6=(0.25,0.5) [5,1,3] 4=(0.5,1) [5,3]
-id=1 1=(0,0.25) [6,2] 5=(0.25,0.5) [2,4,6] 3=(0.5,1) [8,6,4] id=2 2=(0,0.25) [5,1] 6=(0.25,0.5) [5,1,3] 4=(0.5,0.75) [5,3] 8=(0.75,1) [3]
-id=1 1=(0,0.25) [6,2] 5=(0.25,0.5) [2,4,6] 3=(0.5,0.75) [8,6,4] 7=(0.75,1) [4,8] id=2 2=(0,0.25) [5,1] 6=(0.25,0.5) [5,1,3] 4=(0.5,0.75) [7,5,3] 8=(0.75,1) [7,3]
-id=1 1=(0,0.25) [6,2] 5=(0.25,0.5) [2,4,6] 3=(0.5,0.75) [8,6,4] 7=(0.75,1) [10,4,8] id=2 2=(0,0.25) [5,1] 6=(0.25,0.5) [5,1,3] 4=(0.5,0.75) [7,5,3] 8=(0.75,0.875) [7,3] 10=(0.875,1) [7]
-id=1 1=(0,0.25) [6,2] 5=(0.25,0.5) [2,4,6] 3=(0.5,0.75) [8,6,4] 7=(0.75,0.875) [10,4,8] 9=(0.875,1) [8,10] id=2 2=(0,0.25) [5,1] 6=(0.25,0.5) [5,1,3] 4=(0.5,0.75) [7,5,3] 8=(0.75,0.875) [9,7,3] 10=(0.875,1) [9,7]
-id=1 1=(0,0.25) [12,6,2] 5=(0.25,0.5) [12,4,6] 3=(0.5,0.75) [8,6,4] 7=(0.75,0.875) [10,4,8] 9=(0.875,1) [8,10] id=2 2=(0,0.125) [1] 12=(0.125,0.25) [1,5] 6=(0.25,0.5) [5,1,3] 4=(0.5,0.75) [7,5,3] 8=(0.75,0.875) [9,7,3] 10=(0.875,1) [9,7]
-id=1 1=(0,0.125) [12,2] 11=(0.125,0.25) [2,6,12] 5=(0.25,0.5) [12,4,6] 3=(0.5,0.75) [8,6,4] 7=(0.75,0.875) [10,4,8] 9=(0.875,1) [8,10] id=2 2=(0,0.125) [11,1] 12=(0.125,0.25) [11,1,5] 6=(0.25,0.5) [11,5,3] 4=(0.5,0.75) [7,5,3] 8=(0.75,0.875) [9,7,3] 10=(0.875,1) [9,7]
-id=1 1=(0,0.125) [12,2] 11=(0.125,0.25) [2,6,12] 5=(0.25,0.5) [14,12,4,6] 3=(0.5,0.75) [14,8,4] 7=(0.75,0.875) [10,4,8] 9=(0.875,1) [8,10] id=2 2=(0,0.125) [11,1] 12=(0.125,0.25) [11,1,5] 6=(0.25,0.375) [11,5] 14=(0.375,0.5) [3,5] 4=(0.5,0.75) [7,5,3] 8=(0.75,0.875) [9,7,3] 10=(0.875,1) [9,7]
-id=1 1=(0,0.125) [12,2] 11=(0.125,0.25) [2,6,12] 5=(0.25,0.375) [14,12,6] 13=(0.375,0.5) [6,4,14] 3=(0.5,0.75) [14,8,4] 7=(0.75,0.875) [10,4,8] 9=(0.875,1) [8,10] id=2 2=(0,0.125) [11,1] 12=(0.125,0.25) [11,1,5] 6=(0.25,0.375) [13,11,5] 14=(0.375,0.5) [13,3,5] 4=(0.5,0.75) [13,7,3] 8=(0.75,0.875) [9,7,3] 10=(0.875,1) [9,7]
-id=1 1=(0,0.125) [12,2] 11=(0.125,0.25) [2,6,12] 5=(0.25,0.375) [14,12,6] 13=(0.375,0.5) [6,4,14] 3=(0.5,0.75) [16,14,8,4] 7=(0.75,0.875) [16,10,8] 9=(0.875,1) [8,10] id=2 2=(0,0.125) [11,1] 12=(0.125,0.25) [11,1,5] 6=(0.25,0.375) [13,11,5] 14=(0.375,0.5) [13,3,5] 4=(0.5,0.625) [13,3] 16=(0.625,0.75) [3,7] 8=(0.75,0.875) [9,7,3] 10=(0.875,1) [9,7]
-id=1 1=(0,0.125) [12,2] 11=(0.125,0.25) [2,6,12] 5=(0.25,0.375) [14,12,6] 13=(0.375,0.5) [6,4,14] 3=(0.5,0.625) [16,14,4] 15=(0.625,0.75) [4,8,16] 7=(0.75,0.875) [16,10,8] 9=(0.875,1) [8,10] id=2 2=(0,0.125) [11,1] 12=(0.125,0.25) [11,1,5] 6=(0.25,0.375) [13,11,5] 14=(0.375,0.5) [13,3,5] 4=(0.5,0.625) [15,13,3] 16=(0.625,0.75) [15,3,7] 8=(0.75,0.875) [15,9,7] 10=(0.875,1) [9,7]
-id=1 1=(0,0.125) [12,2] 11=(0.125,0.25) [18,2,6,12] 5=(0.25,0.375) [18,14,6] 13=(0.375,0.5) [6,4,14] 3=(0.5,0.625) [16,14,4] 15=(0.625,0.75) [4,8,16] 7=(0.75,0.875) [16,10,8] 9=(0.875,1) [8,10] id=2 2=(0,0.125) [11,1] 12=(0.125,0.1875) [11,1] 18=(0.1875,0.25) [5,11] 6=(0.25,0.375) [13,11,5] 14=(0.375,0.5) [13,3,5] 4=(0.5,0.625) [15,13,3] 16=(0.625,0.75) [15,3,7] 8=(0.75,0.875) [15,9,7] 10=(0.875,1) [9,7]
-setPerp t=0 cPt=(78,4565) == oppT=0 fPerpPt=(78,4565)
-setPerp t=0.125 cPt=(78.1001678,4563.90822) == oppT=0.125 fPerpPt=(78.1001678,4563.90822)
-setPerp t=0.1875 cPt=(78.2316063,4563.34905) == oppT=0.1875 fPerpPt=(78.2316063,4563.34905)
-setPerp t=0.25 cPt=(78.4212702,4562.79143) == oppT=0.25 fPerpPt=(78.4212702,4562.79143)
-setPerp t=0.375 cPt=(78.9780269,4561.71674) == oppT=0.375 fPerpPt=(78.9780269,4561.71674)
-setPerp t=0.5 cPt=(79.7573593,4560.75736) == oppT=0.5 fPerpPt=(79.7573593,4560.75736)
-setPerp t=0.625 cPt=(80.7167415,4559.97803) == oppT=0.625 fPerpPt=(80.7167415,4559.97803)
-setPerp t=0.75 cPt=(81.7914318,4559.42127) == oppT=0.75 fPerpPt=(81.7914318,4559.42127)
-setPerp t=0.875 cPt=(82.9082217,4559.10017) == oppT=0.875 fPerpPt=(82.9082217,4559.10017)
-setPerp t=1 cPt=(84,4559) == oppT=1 fPerpPt=(84,4559)
-setPerp t=0 cPt=(78,4565) == oppT=0 fPerpPt=(78,4565)
-setPerp t=1 cPt=(84,4559) == oppT=1 fPerpPt=(84,4559)
-id=1 (empty) id=2 (empty)
 debugShowConicIntersection wtTs[0]=0 {{{{78,4565}, {78,4559}, {84,4559}}}, 0.707106769} {{78,4565}} wtTs[1]=1 {{84,4559}} wnTs[0]=0 {{{{78,4565}, {78,4559}, {84,4559}}}, 0.707106769} wnTs[1]=1
 debugShowConicLineIntersection wtTs[0]=1 {{{{78,4565}, {78,4559}, {84,4559}}}, 0.707106769} {{84,4559}} wnTs[0]=0 {{{84,4559}, {158,4559}}}
 debugShowConicLineIntersection wtTs[0]=1 {{{{78,4565}, {78,4559}, {84,4559}}}, 0.707106769} {{84,4559}} wnTs[0]=0 {{{84,4559}, {1170,4559}}}
@@ -114,24 +53,9 @@
 debugShowLineIntersection wtTs[0]=0 {{{158,4559}, {158,4596}}} {{158,4559}} wnTs[0]=1 {{{84,4559}, {158,4559}}}
 debugShowLineIntersection wtTs[0]=0 {{{158,4596}, {84,4596}}} {{158,4596}} wnTs[0]=1 {{{158,4559}, {158,4596}}}
 debugShowConicLineIntersection wtTs[0]=0 {{{{84,4596}, {78,4596}, {78,4590}}}, 0.707106769} {{84,4596}} wnTs[0]=1 {{{158,4596}, {84,4596}}}
-------------x--------  start
-------------x--------  moveMultiples
-------------x--------  findCollapsed
-------------x--------  moveNearby
-------------x--------  align
-------------x--------  fixAligned
-------------x--------  addAlignIntersections
-------------x--------  expand2
-------------x--------  mark1
-------------x--------  missingCoincidence1
-------------x--------  expand3
-------------x--------  addExpanded2
-------------x--------  missingCoincidence2
 SkOpSegment::markDone id=8 (84,4559 1170,4559) t=0 [15] (84,4559) tEnd=0.0681399632 newWindSum=? newOppSum=? oppSum=? windSum=? windValue=0 oppValue=0
 SkOpSegment::markDone id=10 (78,4565 78,4559 84,4559) t=0 [19] (78,4565) tEnd=1 newWindSum=? newOppSum=? oppSum=? windSum=? windValue=0 oppValue=0
 SkOpSegment::markDone id=6 (78,4590.00586 78,4565) t=0.000234320081 [33] (78,4590) tEnd=1 newWindSum=? newOppSum=? oppSum=? windSum=? windValue=0 oppValue=0
-------------x--------  pairs->apply
-------------x--------  pairs->findOverlaps
 SkOpSegment::sortAngles [4] tStart=0.931066176 [29]
 SkOpAngle::after [4/1] 31/31 tStart=0.931066176 tEnd=0 < [12/14] 7/7 tStart=0.972972973 tEnd=0 < [4/2] 15/15 tStart=0.931066176 tEnd=1  T 4
 SkOpAngle::afterPart {{{158,4595}, {1171,4595}}} id=4
@@ -151,13 +75,13 @@
 SkOpAngle::afterPart {{{158,4595}, {1171,4595}}} id=4
 SkOpSegment::sortAngles [5] tStart=0.999339899 [31]
 SkOpAngle::after [5/3] 25/29 tStart=0.999339899 tEnd=0 < [14/16] 25/29 tStart=0.998759893 tEnd=0 < [5/4] 9/9 tStart=0.999339899 tEnd=1  F 12
-SkOpAngle::afterPart {{{{78.0000076,4590.01074}, {78.0133288,4595}, {83,4595}}}, 0.877537966} id=5
-SkOpAngle::afterPart {{{{78.0000076,4590.01074}, {78.0105173,4596}, {84,4596}}}, 0.877548993} id=14
-SkOpAngle::afterPart {{{{78.0000076,4590.01074}, {78.0000041,4590.00819}, {78,4590.00586}}}, 0.999999881} id=5
+SkOpAngle::afterPart {{{{78.0000076,4590.01074}, {78.0133288,4595}, {83,4595}}}, 0.708050251} id=5
+SkOpAngle::afterPart {{{{78.0000076,4590.01074}, {78.0105173,4596}, {84,4596}}}, 0.707726777} id=14
+SkOpAngle::afterPart {{{{78.0000076,4590.01074}, {78.0000041,4590.00819}, {78,4590.00586}}}, 1} id=5
 SkOpAngle::after [5/3] 25/29 tStart=0.999339899 tEnd=0 < [14/17] 9/9 tStart=0.998759893 tEnd=1 < [5/4] 9/9 tStart=0.999339899 tEnd=1  T 11
-SkOpAngle::afterPart {{{{78.0000076,4590.01074}, {78.0133288,4595}, {83,4595}}}, 0.877537966} id=5
+SkOpAngle::afterPart {{{{78.0000076,4590.01074}, {78.0133288,4595}, {83,4595}}}, 0.708050251} id=5
 SkOpAngle::afterPart {{{{78.0000076,4590.01074}, {78,4590.00526}, {78,4590}}}, 0.999999642} id=14
-SkOpAngle::afterPart {{{{78.0000076,4590.01074}, {78.0000041,4590.00819}, {78,4590.00586}}}, 0.999999881} id=5
+SkOpAngle::afterPart {{{{78.0000076,4590.01074}, {78.0000041,4590.00819}, {78,4590.00586}}}, 1} id=5
 SkOpSegment::sortAngles [6] tStart=0.000234320081 [33]
 SkOpAngle::after [6/5] 23/23 tStart=0.000234320081 tEnd=0 < [9/9] 7/7 tStart=0 tEnd=1 < [14/18] 21/21 tStart=1 tEnd=0.998759893  T 4
 SkOpAngle::afterPart {{{78,4590}, {78,4590.00586}}} id=6
@@ -231,7 +155,7 @@
 SkOpSegment::markDone id=12 (158,4559 158,4596) t=0 [23] (158,4559) tEnd=0.972972973 newWindSum=-1 newOppSum=-1 oppSum=-1 windSum=-1 windValue=1 oppValue=0
 SkOpSegment::findNextOp chase.append segment=12 span=30 windSum=-2147483647
 SkOpSegment::markDone id=8 (84,4559 1170,4559) t=0.0681399632 [34] (158,4559) tEnd=1 newWindSum=-1 newOppSum=0 oppSum=0 windSum=-1 windValue=1 oppValue=0
-SkOpSegment::findNextOp from:[8] to:[11] start=8985900 end=8985796
+SkOpSegment::findNextOp from:[8] to:[11] start=6561036 end=6560932
 bridgeOp current id=8 from=(1170,4559) to=(158,4559)
 SkOpSegment::findNextOp simple
 SkOpSegment::markDone id=11 (84,4559 158,4559) t=0 [21] (84,4559) tEnd=1 newWindSum=-1 newOppSum=-1 oppSum=-1 windSum=-1 windValue=1 oppValue=1
@@ -257,7 +181,7 @@
 SkOpSegment::markDone id=5 (83,4595 78.0086746,4595 78,4590.00586) t=0.999339899 [31] (78.0000076,4590.01074) tEnd=1 newWindSum=-1 newOppSum=-1 oppSum=-1 windSum=-1 windValue=1 oppValue=0
 SkOpSegment::findNextOp chase.append segment=5 span=31 windSum=-1
 SkOpSegment::markDone id=9 (78,4590 78,4565) t=0 [17] (78,4590) tEnd=1 newWindSum=-1 newOppSum=-1 oppSum=-1 windSum=-1 windValue=1 oppValue=1
-SkOpSegment::findNextOp from:[9] to:[14] start=8986620 end=8987068
+SkOpSegment::findNextOp from:[9] to:[14] start=6561756 end=6562204
 bridgeOp current id=9 from=(78,4565) to=(78,4590)
 SkOpSegment::markWinding id=14 (84,4596 78,4596 78,4590) t=0 [27] (84,4596) tEnd=0.998759893 newWindSum=-2 newOppSum=0 oppSum=? windSum=? windValue=1 oppValue=0
 SkOpSegment::markWinding id=13 (158,4596 84,4596) t=0 [25] (158,4596) tEnd=1 newWindSum=-2 newOppSum=0 oppSum=? windSum=? windValue=1 oppValue=0
@@ -281,7 +205,7 @@
 SkOpSegment::markDone id=4 (1171,4595 83,4595) t=0.931066176 [29] (158,4595) tEnd=1 newWindSum=-1 newOppSum=-2 oppSum=-2 windSum=-1 windValue=1 oppValue=0
 SkOpSegment::findNextOp chase.append segment=4 span=29 windSum=-1
 SkOpSegment::markDone id=14 (84,4596 78,4596 78,4590) t=0.998759893 [32] (78.0000076,4590.01074) tEnd=1 newWindSum=-1 newOppSum=0 oppSum=0 windSum=-1 windValue=1 oppValue=0
-SkOpSegment::findNextOp from:[14] to:[5] start=8986964 end=8984396
+SkOpSegment::findNextOp from:[14] to:[5] start=6562100 end=6559532
 bridgeOp current id=14 from=(78,4590) to=(78.0000076,4590.01074)
 path.lineTo(78,4590);
 path.conicTo(78,4590.00537, 78.0000076,4590.01074, 0.999999642);
@@ -304,6 +228,8 @@
 path.lineTo(1176,4565);
 </div>
 
+
+
 </div>
 
 <script type="text/javascript">
@@ -1461,7 +1387,7 @@
 
 function curve_extremes(curve, bounds) {
     var length = curve.length == 7 ? 6 : curve.length;
-    for (var index = 0; index < curve.length; index += 2) {
+    for (var index = 0; index < length; index += 2) {
         var x = curve[index];
         var y = curve[index + 1];
         bounds[0] = Math.min(bounds[0], x);
@@ -1988,10 +1914,16 @@
     var bz = 2 * dz - (az + cz) / 2;
     var dt = t2 - t1;
     var dt_1 = 1 - dt;
-    var partW = (1 + dt * (w - 1)) / Math.sqrt(dt * dt + 2 * dt * dt_1 * w + dt_1 * dt_1);
     var array = [
-        ax / az, ay / az, bx / bz, by / bz, cx / cz, cy / cz, partW
+        ax / az, ay / az, bx / bz, by / bz, cx / cz, cy / cz, 0
     ];
+    var dMidAC = { x:(array[0] + array[4]) / 2, y:(array[1] + array[5]) / 2 };
+    var dMid = { x:dx / dz, y:dy / dz };
+    var dWNumer = { x:dMidAC.x - dMid.x, y:dMidAC.y - dMid.y };
+    var dWDenom = { x:dMid.x - array[2], y:dMid.y - array[3] };
+    var partW = Math.sqrt(dWNumer.x * dWNumer.x + dWNumer.y * dWNumer.y)
+                / Math.sqrt(dWDenom.x * dWDenom.x + dWDenom.y * dWDenom.y);
+    array[6] = partW;
     return array;
 }