Working arrange_objects with DJD selection heuristic and a bottom-left placement strategy.

xs/src/libslic3r/Point.cpp

@@ -1,6 +1,7 @@
 #include "Point.hpp"
 #include "Line.hpp"
 #include "MultiPoint.hpp"
+#include "Int128.hpp"
 #include <algorithm>
 #include <cmath>
 
@@ -375,4 +376,20 @@ Pointf3::vector_to(const Pointf3 &point) const
     return Vectorf3(point.x - this->x, point.y - this->y, point.z - this->z);
 }
 
+namespace int128 {
+
+int orient(const Point &p1, const Point &p2, const Point &p3)
+{
+    Slic3r::Vector v1(p2 - p1);
+    Slic3r::Vector v2(p3 - p1);
+    return Int128::sign_determinant_2x2_filtered(v1.x, v1.y, v2.x, v2.y);
+}
+
+int cross(const Point &v1, const Point &v2)
+{
+    return Int128::sign_determinant_2x2_filtered(v1.x, v1.y, v2.x, v2.y);
+}
+
+}
+
 }