From dde4779cbbe811f987031d7fe6cba3221eef15ee Mon Sep 17 00:00:00 2001
From: Joseph Lenox <lenox.joseph@gmail.com>
Date: Tue, 31 Jul 2018 23:19:44 -0500
Subject: [PATCH] added grow() method for Polyline; moved CLIPPER_OFFSET_SCALE
 to libslic3r to avoid include loops

---
 xs/src/libslic3r/ClipperUtils.hpp | 1 -
 xs/src/libslic3r/Polyline.cpp     | 7 +++++++
 xs/src/libslic3r/Polyline.hpp     | 2 ++
 xs/src/libslic3r/libslic3r.h      | 2 ++
 4 files changed, 11 insertions(+), 1 deletion(-)

diff --git a/xs/src/libslic3r/ClipperUtils.hpp b/xs/src/libslic3r/ClipperUtils.hpp
index ddd551ca2..4a5dcbf1c 100644
--- a/xs/src/libslic3r/ClipperUtils.hpp
+++ b/xs/src/libslic3r/ClipperUtils.hpp
@@ -19,7 +19,6 @@ namespace Slic3r {
 // How about 2^17=131072?
 // By the way, is the scalling needed at all? Cura runs all the computation with a fixed point precision of 1um, while Slic3r scales to 1nm,
 // further scaling by 10e5 brings us to 
-constexpr float CLIPPER_OFFSET_SCALE = 100000.0;
 constexpr auto MAX_COORD = ClipperLib::hiRange / CLIPPER_OFFSET_SCALE;
 
 //-----------------------------------------------------------
diff --git a/xs/src/libslic3r/Polyline.cpp b/xs/src/libslic3r/Polyline.cpp
index 3c371ae71..b80335073 100644
--- a/xs/src/libslic3r/Polyline.cpp
+++ b/xs/src/libslic3r/Polyline.cpp
@@ -3,6 +3,7 @@
 #include "ExPolygonCollection.hpp"
 #include "Line.hpp"
 #include "Polygon.hpp"
+#include "ClipperUtils.hpp"
 #include <iostream>
 #include <utility>
 
@@ -220,6 +221,12 @@ Polyline::wkt() const
     return wkt.str();
 }
 
+Polygons
+Polyline::grow(double delta, double scale, ClipperLib::JoinType joinType, double miterLimit) const
+{
+    return offset(*this, delta, scale, joinType, miterLimit);
+}
+
 ThickLines
 ThickPolyline::thicklines() const
 {
diff --git a/xs/src/libslic3r/Polyline.hpp b/xs/src/libslic3r/Polyline.hpp
index dfd87fef7..49e261bdf 100644
--- a/xs/src/libslic3r/Polyline.hpp
+++ b/xs/src/libslic3r/Polyline.hpp
@@ -7,6 +7,7 @@
 #include "Polygon.hpp"
 #include <string>
 #include <vector>
+#include "clipper.hpp"
 
 namespace Slic3r {
 
@@ -32,6 +33,7 @@ class Polyline : public MultiPoint {
     void split_at(const Point &point, Polyline* p1, Polyline* p2) const;
     bool is_straight() const;
     std::string wkt() const;
+    Polygons grow(double delta, double scale = CLIPPER_OFFSET_SCALE, ClipperLib::JoinType joinType = ClipperLib::jtSquare, double miterLimit = 3.0) const;
 };
 
 class ThickPolyline : public Polyline {
diff --git a/xs/src/libslic3r/libslic3r.h b/xs/src/libslic3r/libslic3r.h
index da6aaa7ce..18e1d0acd 100644
--- a/xs/src/libslic3r/libslic3r.h
+++ b/xs/src/libslic3r/libslic3r.h
@@ -81,6 +81,8 @@ constexpr coordf_t INSET_OVERLAP_TOLERANCE = 0.4;
 constexpr coordf_t EXTERNAL_INFILL_MARGIN = 3;
 constexpr coord_t SCALED_EXTERNAL_INFILL_MARGIN = scale_(EXTERNAL_INFILL_MARGIN);
 
+constexpr float CLIPPER_OFFSET_SCALE = 100000.0;
+
 enum Axis { X=0, Y, Z };
 
 template <class T>