Partial store to svg

src/libslic3r/NSVGUtils.cpp

@@ -3,6 +3,10 @@
 
 namespace {
 Slic3r::Polygons to_polygons(const NSVGshape &shape, float tessTol, int max_level, float scale, bool is_y_negative);
+
+// see function nsvg__lineTo(NSVGparser* p, float x, float y)
+bool is_line(const float *p, float precision = 1e-4);
+
 } // namespace
 
 namespace Slic3r {
@@ -34,23 +38,102 @@ NSVGimage_ptr nsvgParseFromFile(const std::string &filename, const char *units,
 
 bool save(const NSVGimage &image, const std::string &svg_file_path) 
 {
-    //BoundingBox bb = get_extents(to_polygons(image));
     FILE * file = boost::nowide::fopen(svg_file_path.c_str(), "w");
     if (file == NULL)
         return false;
 
-    fprintf(file, "<svg xmlns=\"http://www.w3.org/2000/svg\">\n");    
+    fprintf(file, "<?xml version=\"1.0\" encoding=\"UTF-8\" standalone=\"no\"?>");
+
+    Vec2f tl(std::numeric_limits<float>::max(), std::numeric_limits<float>::max());
+    Vec2f br(std::numeric_limits<float>::min(), std::numeric_limits<float>::min());
+    for (const NSVGshape *shape = image.shapes; shape != NULL; shape = shape->next) 
+        for (const NSVGpath *path = shape->paths; path != NULL; path = path->next) {
+            if (tl.x() > path->bounds[0])
+                tl.x() = path->bounds[0];
+            if (tl.y() > path->bounds[1])
+                tl.y() = path->bounds[1];
+            if (br.x() < path->bounds[2])
+                br.x() = path->bounds[2];
+            if (br.y() < path->bounds[3])
+                br.y() = path->bounds[3];
+        }
+
+    tl.x() = std::floor(tl.x());
+    tl.y() = std::floor(tl.y());
+
+    br.x() = std::ceil(br.x());
+    br.y() = std::ceil(br.y());
+    Vec2f s = br - tl;
+
+    //// IMPROVE: use path bounds instead of BoundingBox
+    //BoundingBox bb = get_extents(to_polygons(image)); 
+    //// bb has opposit value of y axe
+    //// Values stored in point are fixed point numbers need extend
+    //Point s = bb.size() + Point(2, 2); // extended size
+    //Point tl(bb.min.x() - 1, -bb.max.y() - 1); // top left corner
+    //Point br(tl.x() + s.x(), tl.y() + s.y());  // bottom right
+
+    fprintf(file, "<svg xmlns=\"http://www.w3.org/2000/svg\" width=\"%dmm\" height=\"%dmm\" viewBox=\"%d %d %d %d\" >\n", 
+        (int)s.x(), (int)s.y(), (int)tl.x(), (int)tl.y(), (int)br.x(), (int)br.y());
+    fprintf(file, "<!-- Created with PrusaSlicer (https://www.prusa3d.com/prusaslicer/) -->\n");
+
+    auto write_point = [](std::string &d, const float *p) { 
+        d += std::to_string(p[0]) + "," + std::to_string(p[1]) + " ";
+    };
+
     for (const NSVGshape *shape = image.shapes; shape != NULL; shape = shape->next) {
+        enum struct Type { move, line, curve, close }; // https://developer.mozilla.org/en-US/docs/Web/SVG/Attribute/d
+        Type type = Type::move;
         std::string d = "M "; // move on start point
         for (const NSVGpath *path = shape->paths; path != NULL; path = path->next) {
-            size_t path_size = (path->npts > 1) ? static_cast<size_t>(path->npts - 1) : 0;
+            if (path->npts <= 1)
+                continue;
+
+            if (type == Type::close) {
+                Type type = Type::move;
+                // NOTE: After close must be a space
+                d += " M "; // move on start point
+            }
+            //write_point(d, path->pts);
+            d += std::to_string(path->pts[0]) + "," + std::to_string(path->pts[1]) + " ";
+            size_t path_size = static_cast<size_t>(path->npts - 1);
+
+            if (path->closed) {
+                // Do not use last point in path it is duplicit
+                if (path->npts <= 4)
+                    continue;
+                path_size = static_cast<size_t>(path->npts - 4);
+            }
+
             for (size_t i = 0; i < path_size; i += 3) {
                 const float *p = &path->pts[i * 2];
-                d += std::to_string(p[0]) + "," + std::to_string(p[1]) + " ";
+                if (!::is_line(p)) {
+                    if (type != Type::curve) {
+                        type = Type::curve;
+                        d += "C "; // start sequence of triplets defining curves
+                    }
+                    
+                    d += std::to_string(p[2]) + "," + std::to_string(p[3]) + " " +
+                         std::to_string(p[4]) + "," + std::to_string(p[5]) + " " ;
+                } else {
+
+                    if (type != Type::line) {
+                        type = Type::line;
+                        d += "L "; // start sequence of line points
+                    }
+                }
+                d += std::to_string(p[6]) + "," + std::to_string(p[7]) + " ";
+            }
+            if (path->closed) {
+                type = Type::close;
+                d += "Z"; // start sequence of line points
             }
         }
-        d += "Z"; // closed path
+        if (type != Type::close) {
-        fprintf(file, "   <path fill=\"#D2D2D2\" d=\"%s\" />\n", d.c_str());
+            type = Type::close;
+            d += "Z"; // closed path
+        }
+        fprintf(file, "<path fill=\"#D2D2D2\" d=\"%s\" />\n", d.c_str());
     }
     fprintf(file, "</svg>\n");
     fclose(file);
@@ -91,7 +174,7 @@ bool need_flattening(float tessTol, const Vec2f &p1, const Vec2f &p2, const Vec2
 }
 
 // see function nsvg__lineTo(NSVGparser* p, float x, float y)
-bool is_line(const float *p, float precision = 1e-4){
+bool is_line(const float *p, float precision){
     //Vec2f p1(p[0], p[1]);
     //Vec2f p2(p[2], p[3]);
     //Vec2f p3(p[4], p[5]);