Add polygon wkt reading/writing

CURA-11361

include/utils/polygon.h

@@ -1509,6 +1509,21 @@ class Polygons
     }
 
     Polygons offset(const std::vector<coord_t>& offset_dists) const;
+
+    /*!
+     * @brief Export the polygon to a WKT string
+     *
+     * @param stream The stream to write to
+     */
+    void writeWkt(std::ostream& stream) const;
+
+    /*!
+     * @brief Import the polygon from a WKT string
+     *
+     * @param wkt The WKT string to read from
+     * @return Polygons The polygons read from the stream
+     */
+    static Polygons fromWkt(const std::string& wkt);
 };
 
 /*!

src/utils/polygon.cpp

@@ -3,18 +3,21 @@
 
 #include "utils/polygon.h"
 
-#include <numeric>
 #include <unordered_set>
 
-#include <range/v3/view/zip.hpp>
-#include <range/v3/range/primitives.hpp>
+#include <boost/geometry/io/wkt/read.hpp>
+#include <boost/geometry/geometries/point_xy.hpp>
+#include <boost/geometry/geometries/polygon.hpp>
+#include <fmt/format.h>
+#include <range/v3/to_container.hpp>
+#include <range/v3/view/c_str.hpp>
 #include <range/v3/view/filter.hpp>
-
-#include "utils/linearAlg2D.h" // pointLiesOnTheRightOfLine
+#include <range/v3/view/join.hpp>
+#include <range/v3/view/transform.hpp>
 
 #include "utils/ListPolyIt.h"
-
 #include "utils/PolylineStitcher.h"
+#include "utils/linearAlg2D.h" // pointLiesOnTheRightOfLine
 
 namespace cura
 {
@@ -775,6 +778,55 @@ Polygons Polygons::toPolygons(ClipperLib::PolyTree& poly_tree)
     return ret;
 }
 
+Polygons Polygons::fromWkt(const std::string& wkt)
+{
+    typedef boost::geometry::model::d2::point_xy<double> point_type;
+    typedef boost::geometry::model::polygon<point_type> polygon_type;
+
+    polygon_type poly;
+    boost::geometry::read_wkt(wkt, poly);
+
+    Polygons ret;
+
+    Polygon outer;
+    for (const auto& point: poly.outer())
+    {
+        outer.add(Point(point.x(), point.y()));
+    }
+    ret.add(outer);
+
+    for (const auto& hole: poly.inners())
+    {
+        Polygon inner;
+        for (const auto& point: hole)
+        {
+            inner.add(Point(point.x(), point.y()));
+        }
+        ret.add(inner);
+    }
+
+    return ret;
+}
+
+void Polygons::writeWkt(std::ostream& stream) const
+{
+    stream << "POLYGON (";
+    const auto paths_str = paths
+                         | ranges::views::transform([](const auto& path) {
+                                const auto path_str
+                                    = path
+                                    | ranges::views::transform([](const auto& point) { return fmt::format("{} {}", point.X, point.Y); })
+                                    | ranges::views::join(ranges::views::c_str(", "))
+                                    | ranges::to<std::string>();
+                                return "(" + path_str + ")";
+                            })
+                         | ranges::views::join(ranges::views::c_str(" "))
+                         | ranges::to<std::string>();
+
+    stream << paths_str;
+    stream << ")";
+}
+
 bool ConstPolygonRef::smooth_corner_complex(const Point p1, ListPolyIt& p0_it, ListPolyIt& p2_it, const int64_t shortcut_length)
 {
     // walk away from the corner until the shortcut > shortcut_length or it would smooth a piece inward