Track leading point as well

1 files changed, 4 insertions, 2 deletions

diff --git a/sigmodr/widgets/mapeditor/WorldMapPlacement.cpp b/sigmodr/widgets/mapeditor/WorldMapPlacement.cpp
index 0b66a662..6f603f7d 100644
--- a/sigmodr/widgets/mapeditor/WorldMapPlacement.cpp
+++ b/sigmodr/widgets/mapeditor/WorldMapPlacement.cpp
@@ -115,8 +115,9 @@ template<typename T> static bool between(const T& middle, const T& end1, const T
 static CollisionInfo findCollisions(const QPolygon& polygon1, const QPolygon& polygon2)
 {
     CollisionInfo data;
-    QPoint prevPoint1 = polygon1.last();
-    foreach (const QPoint& point1, polygon1)
+    QPoint prevPoint1 = polygon1[polygon1.size() - 2];
+    QPoint point1 = polygon1.last();
+    foreach (const QPoint& nextPoint1, polygon1)
     {
         QPoint prevPoint2 = polygon2.last();
         foreach (const QPoint& point2, polygon2)
@@ -144,6 +145,7 @@ static CollisionInfo findCollisions(const QPolygon& polygon1, const QPolygon& po
             }
             prevPoint2 = point2;
         }
+        point1 = nextPoint1;
         prevPoint1 = point1;
     }
     return data;