Ported ExtrusionPath::Collection->chained_path

xs/src/ExtrusionEntityCollection.cpp

@@ -0,0 +1,75 @@
+#include "ExtrusionEntityCollection.hpp"
+
+namespace Slic3r {
+
+ExtrusionEntityCollection*
+ExtrusionEntityCollection::clone() const
+{
+    return new ExtrusionEntityCollection (*this);
+}
+
+void
+ExtrusionEntityCollection::reverse()
+{
+    for (ExtrusionEntitiesPtr::iterator it = this->entities.begin(); it != this->entities.end(); ++it) {
+        (*it)->reverse();
+    }
+    std::reverse(this->entities.begin(), this->entities.end());
+}
+
+Point*
+ExtrusionEntityCollection::first_point()
+{
+    return this->entities.front()->first_point();
+}
+
+Point*
+ExtrusionEntityCollection::last_point()
+{
+    return this->entities.back()->last_point();
+}
+
+ExtrusionEntityCollection*
+ExtrusionEntityCollection::chained_path(bool no_reverse) const
+{
+    if (this->entities.empty()) {
+        return new ExtrusionEntityCollection ();
+    }
+    return this->chained_path_from(this->entities.front()->first_point(), no_reverse);
+}
+
+ExtrusionEntityCollection*
+ExtrusionEntityCollection::chained_path_from(Point* start_near, bool no_reverse) const
+{
+    if (this->no_sort) return new ExtrusionEntityCollection(*this);
+    ExtrusionEntityCollection* retval = new ExtrusionEntityCollection;
+    ExtrusionEntitiesPtr my_paths = this->entities;
+    
+    Points endpoints;
+    for (ExtrusionEntitiesPtr::iterator it = my_paths.begin(); it != my_paths.end(); ++it) {
+        endpoints.push_back(*(*it)->first_point());
+        if (no_reverse) {
+            endpoints.push_back(*(*it)->first_point());
+        } else {
+            endpoints.push_back(*(*it)->last_point());
+        }
+    }
+    
+    while (!my_paths.empty()) {
+        // find nearest point
+        int start_index = start_near->nearest_point_index(endpoints);
+        int path_index = start_index/2;
+        if (start_index % 2 && !no_reverse) {
+            my_paths.at(path_index) = my_paths.at(path_index)->clone();  // maybe we should clone them all when building my_paths?
+            my_paths.at(path_index)->reverse();
+        }
+        retval->entities.push_back(my_paths.at(path_index));
+        my_paths.erase(my_paths.begin() + path_index);
+        endpoints.erase(endpoints.begin() + 2*path_index, endpoints.begin() + 2*path_index + 2);
+        start_near = retval->entities.back()->last_point();
+    }
+    
+    return retval;
+}
+
+}