Fixed issue #903. Bug in tool Cut Spline path.

(grafted from a5d6d7a0bd903897c2b509f90af1e50206feec0e)

--HG--
branch : develop

ChangeLog.txt

@@ -3,6 +3,9 @@
 - [#894] Quick way to disable a passmark.
 - [#895] Improve path validation. Do not allow repeat the same curve twice.
 
+# Version 0.6.2 (unreleased)
+- [#903] Bug in tool Cut Spline path.
+
 # Version 0.6.1 October 23, 2018
 - [#885] Regression. Broken support for multi size measurements.
 - Fixed issues with seam allowance.

src/libs/vgeometry/vabstractcubicbezierpath.cpp

@@ -27,6 +27,7 @@
  *************************************************************************/
 
 #include "vabstractcubicbezierpath.h"
+#include "vsplinepoint.h"
 
 #include <QPainterPath>
 
@@ -203,7 +204,38 @@ QPointF VAbstractCubicBezierPath::CutSplinePath(qreal length, qint32 &p1, qint32
         {
             p1 = i-1;
             p2 = i;
-            return spl.CutSpline(length - (fullLength - splLength), spl1p2, spl1p3, spl2p2, spl2p3);
+            const QPointF point = spl.CutSpline(length - (fullLength - splLength), spl1p2, spl1p3, spl2p2, spl2p3);
+
+            const QVector<VSplinePoint> points = GetSplinePath();
+
+            if (p1 > 0)
+            {
+                const VSplinePoint splP1 = points.at(p1);
+                QLineF line(splP1.P().toQPointF(), spl1p2);
+                if (qFuzzyIsNull(line.length()))
+                {
+                    spl1p2.rx() += ToPixel(0.1, Unit::Mm);
+                    QLineF line(splP1.P().toQPointF(), spl1p2);
+                    line.setLength(ToPixel(0.1, Unit::Mm));
+                    line.setAngle(splP1.Angle1()+180);
+                    spl1p2 = line.p2();
+                }
+            }
+
+            if (p2 < points.size() - 1)
+            {
+                const VSplinePoint splP2 = points.at(p2);
+                QLineF line(splP2.P().toQPointF(), spl2p3);
+                if (qFuzzyIsNull(line.length()))
+                {
+                    spl2p3.rx() += ToPixel(0.1, Unit::Mm);
+                    QLineF line(splP2.P().toQPointF(), spl2p3);
+                    line.setAngle(splP2.Angle2()+180);
+                    spl2p3 = line.p2();
+                }
+            }
+
+            return point;
         }
     }
     p1 = p2 = -1;