Moved C++ code into new libslic3r directory

1 files changed, 278 insertions, 0 deletions

diff --git a/xs/src/libslic3r/MotionPlanner.cpp b/xs/src/libslic3r/MotionPlanner.cpp
new file mode 100644
index 000000000..82108afd9
--- /dev/null
+++ b/xs/src/libslic3r/MotionPlanner.cpp
@@ -0,0 +1,278 @@
+#include "BoundingBox.hpp"
+#include "MotionPlanner.hpp"
+#include <limits> // for numeric_limits
+
+#include "boost/polygon/voronoi.hpp"
+using boost::polygon::voronoi_builder;
+using boost::polygon::voronoi_diagram;
+
+namespace Slic3r {
+
+MotionPlanner::MotionPlanner(const ExPolygons &islands)
+    : islands(islands), initialized(false)
+{}
+
+MotionPlanner::~MotionPlanner()
+{
+    for (std::vector<MotionPlannerGraph*>::iterator graph = this->graphs.begin(); graph != this->graphs.end(); ++graph)
+        delete *graph;
+}
+
+void
+MotionPlanner::initialize()
+{
+    if (this->initialized) return;
+    
+    ExPolygons expp;
+    for (ExPolygons::const_iterator island = this->islands.begin(); island != this->islands.end(); ++island) {
+        island->simplify(SCALED_EPSILON, expp);
+    }
+    this->islands = expp;
+    
+    // loop through islands in order to create inner expolygons and collect their contours
+    this->inner.reserve(this->islands.size());
+    Polygons outer_holes;
+    for (ExPolygons::const_iterator island = this->islands.begin(); island != this->islands.end(); ++island) {
+        this->inner.push_back(ExPolygonCollection());
+        offset_ex(*island, this->inner.back(), -MP_INNER_MARGIN);
+        
+        outer_holes.push_back(island->contour);
+    }
+    
+    // grow island contours in order to prepare holes of the outer environment
+    // This is actually wrong because it might merge contours that are close,
+    // thus confusing the island check in shortest_path() below
+    //offset(outer_holes, outer_holes, +MP_OUTER_MARGIN);
+    
+    // generate outer contour as bounding box of everything
+    Points points;
+    for (Polygons::const_iterator contour = outer_holes.begin(); contour != outer_holes.end(); ++contour)
+        points.insert(points.end(), contour->points.begin(), contour->points.end());
+    BoundingBox bb(points);
+    
+    // grow outer contour
+    Polygons contour;
+    offset(bb.polygon(), contour, +MP_OUTER_MARGIN);
+    assert(contour.size() == 1);
+    
+    // make expolygon for outer environment
+    ExPolygons outer;
+    diff(contour, outer_holes, outer);
+    assert(outer.size() == 1);
+    this->outer = outer.front();
+    
+    this->graphs.resize(this->islands.size() + 1, NULL);
+    this->initialized = true;
+}
+
+void
+MotionPlanner::shortest_path(const Point &from, const Point &to, Polyline* polyline)
+{
+    if (!this->initialized) this->initialize();
+    
+    // Are both points in the same island?
+    int island_idx = -1;
+    for (ExPolygons::const_iterator island = this->islands.begin(); island != this->islands.end(); ++island) {
+        if (island->contains_point(from) && island->contains_point(to)) {
+            // since both points are in the same island, is a direct move possible?
+            // if so, we avoid generating the visibility environment
+            if (island->contains_line(Line(from, to))) {
+                polyline->points.push_back(from);
+                polyline->points.push_back(to);
+                return;
+            }
+            island_idx = island - this->islands.begin();
+            break;
+        }
+    }
+    
+    // Now check whether points are inside the environment.
+    Point inner_from    = from;
+    Point inner_to      = to;
+    bool from_is_inside, to_is_inside;
+    if (island_idx == -1) {
+        if (!(from_is_inside = this->outer.contains_point(from))) {
+            // Find the closest inner point to start from.
+            from.nearest_point(this->outer, &inner_from);
+        }
+        if (!(to_is_inside = this->outer.contains_point(to))) {
+            // Find the closest inner point to start from.
+            to.nearest_point(this->outer, &inner_to);
+        }
+    } else {
+        if (!(from_is_inside = this->inner[island_idx].contains_point(from))) {
+            // Find the closest inner point to start from.
+            from.nearest_point(this->inner[island_idx], &inner_from);
+        }
+        if (!(to_is_inside = this->inner[island_idx].contains_point(to))) {
+            // Find the closest inner point to start from.
+            to.nearest_point(this->inner[island_idx], &inner_to);
+        }
+    }
+    
+    // perform actual path search
+    MotionPlannerGraph* graph = this->init_graph(island_idx);
+    graph->shortest_path(graph->find_node(inner_from), graph->find_node(inner_to), polyline);
+    
+    polyline->points.insert(polyline->points.begin(), from);
+    polyline->points.push_back(to);
+}
+
+MotionPlannerGraph*
+MotionPlanner::init_graph(int island_idx)
+{
+    if (this->graphs[island_idx + 1] == NULL) {
+        Polygons pp;
+        if (island_idx == -1) {
+            pp = this->outer;
+        } else {
+            pp = this->inner[island_idx];
+        }
+        
+        MotionPlannerGraph* graph = this->graphs[island_idx + 1] = new MotionPlannerGraph();
+        
+        // add polygon boundaries as edges
+        size_t node_idx = 0;
+        Lines lines;
+        for (Polygons::const_iterator polygon = pp.begin(); polygon != pp.end(); ++polygon) {
+            graph->nodes.push_back(polygon->points.back());
+            node_idx++;
+            for (Points::const_iterator p = polygon->points.begin(); p != polygon->points.end(); ++p) {
+                graph->nodes.push_back(*p);
+                double dist = graph->nodes[node_idx-1].distance_to(*p);
+                graph->add_edge(node_idx-1, node_idx, dist);
+                graph->add_edge(node_idx, node_idx-1, dist);
+                node_idx++;
+            }
+            polygon->lines(&lines);
+        }
+        
+        // add Voronoi edges as internal edges
+        {
+            typedef voronoi_diagram<double> VD;
+            typedef std::map<const VD::vertex_type*,size_t> t_vd_vertices;
+            VD vd;
+            t_vd_vertices vd_vertices;
+            
+            boost::polygon::construct_voronoi(lines.begin(), lines.end(), &vd);
+            for (VD::const_edge_iterator edge = vd.edges().begin(); edge != vd.edges().end(); ++edge) {
+                if (edge->is_infinite()) continue;
+                
+                const VD::vertex_type* v0 = edge->vertex0();
+                const VD::vertex_type* v1 = edge->vertex1();
+                Point p0 = Point(v0->x(), v0->y());
+                Point p1 = Point(v1->x(), v1->y());
+                // contains_point() should probably be faster than contains_line(),
+                // and should it fail on any boundary points it's not a big problem
+                if (island_idx == -1) {
+                    if (!this->outer.contains_point(p0) || !this->outer.contains_point(p1)) continue;
+                } else {
+                    if (!this->inner[island_idx].contains_point(p0) || !this->inner[island_idx].contains_point(p1)) continue;
+                }
+                
+                t_vd_vertices::const_iterator i_v0 = vd_vertices.find(v0);
+                size_t v0_idx;
+                if (i_v0 == vd_vertices.end()) {
+                    graph->nodes.push_back(p0);
+                    v0_idx = node_idx;
+                    vd_vertices[v0] = node_idx;
+                    node_idx++;
+                } else {
+                    v0_idx = i_v0->second;
+                }
+                
+                t_vd_vertices::const_iterator i_v1 = vd_vertices.find(v1);
+                size_t v1_idx;
+                if (i_v1 == vd_vertices.end()) {
+                    graph->nodes.push_back(p1);
+                    v1_idx = node_idx;
+                    vd_vertices[v1] = node_idx;
+                    node_idx++;
+                } else {
+                    v1_idx = i_v1->second;
+                }
+                
+                double dist = graph->nodes[v0_idx].distance_to(graph->nodes[v1_idx]);
+                graph->add_edge(v0_idx, v1_idx, dist);
+            }
+        }
+        
+        return graph;
+    }
+    return this->graphs[island_idx + 1];
+}
+
+void
+MotionPlannerGraph::add_edge(size_t from, size_t to, double weight)
+{
+    // extend adjacency list until this start node
+    if (this->adjacency_list.size() < from+1)
+        this->adjacency_list.resize(from+1);
+    
+    this->adjacency_list[from].push_back(neighbor(to, weight));
+}
+
+size_t
+MotionPlannerGraph::find_node(const Point &point) const
+{
+    /*
+    for (Points::const_iterator p = this->nodes.begin(); p != this->nodes.end(); ++p) {
+        if (p->coincides_with(point)) return p - this->nodes.begin();
+    }
+    */
+    return point.nearest_point_index(this->nodes);
+}
+
+void
+MotionPlannerGraph::shortest_path(size_t from, size_t to, Polyline* polyline)
+{
+    const weight_t max_weight = std::numeric_limits<weight_t>::infinity();
+    
+    std::vector<weight_t> min_distance;
+    std::vector<node_t> previous;
+    {
+        int n = this->adjacency_list.size();
+        min_distance.clear();
+        min_distance.resize(n, max_weight);
+        min_distance[from] = 0;
+        previous.clear();
+        previous.resize(n, -1);
+        std::set<std::pair<weight_t, node_t> > vertex_queue;
+        vertex_queue.insert(std::make_pair(min_distance[from], from));
+ 
+        while (!vertex_queue.empty()) 
+        {
+            weight_t dist = vertex_queue.begin()->first;
+            node_t u = vertex_queue.begin()->second;
+            vertex_queue.erase(vertex_queue.begin());
+ 
+            // Visit each edge exiting u
+            const std::vector<neighbor> &neighbors = this->adjacency_list[u];
+            for (std::vector<neighbor>::const_iterator neighbor_iter = neighbors.begin();
+                 neighbor_iter != neighbors.end();
+                 neighbor_iter++)
+            {
+                node_t v = neighbor_iter->target;
+                weight_t weight = neighbor_iter->weight;
+                weight_t distance_through_u = dist + weight;
+                if (distance_through_u < min_distance[v]) {
+                    vertex_queue.erase(std::make_pair(min_distance[v], v));
+                    min_distance[v] = distance_through_u;
+                    previous[v] = u;
+                    vertex_queue.insert(std::make_pair(min_distance[v], v));
+                }
+
+            }
+        }
+    }
+    
+    for (node_t vertex = to; vertex != -1; vertex = previous[vertex])
+        polyline->points.push_back(this->nodes[vertex]);
+    polyline->reverse();
+}
+
+#ifdef SLIC3RXS
+REGISTER_CLASS(MotionPlanner, "MotionPlanner");
+#endif
+
+}