Some image change

IntelliPhoto/Painting/IntelliHelper/IntelliHelper.cpp

@@ -0,0 +1,39 @@
+#include"IntelliHelper.h"
+#include<algorithm>
+
+int IntelliHelper::orientation(QPoint& p1,  QPoint& p2, QPoint& p3){
+    int value = (p2.x()-p1.x())*(p3.x()-p2.x())-
+                (p2.y()-p1.y())*(p3.y()-p2.y());
+    if(value==0) return 0;
+    return (value>0)?1:2;
+}
+
+bool IntelliHelper::onSegment(QPoint& p1, QPoint& q, QPoint& p2){
+    return (q.x() >= std::min(p1.x(),p2.x()) && q.x() <= std::max(p1.x(), p2.x()) &&
+            q.y() >= std::min(p1.y(),p2.y()) && q.y() <= std::max(p1.y(), p2.y()));
+}
+
+bool IntelliHelper::hasIntersection(QPoint& p1, QPoint& q1, QPoint& p2, QPoint& q2){
+    int o1 = IntelliHelper::orientation(p1,q1,p2);
+    int o2 = IntelliHelper::orientation(p1,q1,q2);
+    int o3 = IntelliHelper::orientation(p2,q2,p1);
+    int o4 = IntelliHelper::orientation(p2,q2,q1);
+
+    // General case
+    if (o1 != o2 && o3 != o4)
+        return true;
+
+    // p1, q1 and p2 are colinear and p2 lies on segment p1q1
+    if (o1 == 0 && onSegment(p1, p2, q1)) return true;
+
+    // p1, q1 and q2 are colinear and q2 lies on segment p1q1
+    if (o2 == 0 && onSegment(p1, q2, q1)) return true;
+
+    // p2, q2 and p1 are colinear and p1 lies on segment p2q2
+    if (o3 == 0 && onSegment(p2, p1, q2)) return true;
+
+     // p2, q2 and q1 are colinear and q1 lies on segment p2q2
+    if (o4 == 0 && onSegment(p2, q1, q2)) return true;
+
+    return false; // Doesn't fall in any of the above cases
+}