Introduction of ClipperLib_Z: The Clipper library compiled with support

of the Z coordinate, compiled in the ClipperLib_Z namespace.

Update of Lukas's new brim clipping:
All the brim contours are now clipped by the ClipperLib_Z library
in one shot.

src/clipper/CMakeLists.txt

@@ -4,4 +4,6 @@ cmake_minimum_required(VERSION 2.6)
 add_library(clipper STATIC
     clipper.cpp
     clipper.hpp
+    clipper_z.cpp
+    clipper_z.hpp
 )

src/clipper/clipper.cpp

@@ -51,7 +51,11 @@
 #include <Shiny/Shiny.h>
 #include <libslic3r/Int128.hpp>
 
+#ifdef use_xyz
+namespace ClipperLib_Z {
+#else /* use_xyz */
 namespace ClipperLib {
+#endif /* use_xyz */
 
 static double const pi = 3.141592653589793238;
 static double const two_pi = pi *2;
@@ -1616,7 +1620,7 @@ void Clipper::SetZ(IntPoint& pt, TEdge& e1, TEdge& e2)
   else if (pt == e1.Top) pt.Z = e1.Top.Z;
   else if (pt == e2.Bot) pt.Z = e2.Bot.Z;
   else if (pt == e2.Top) pt.Z = e2.Top.Z;
-  else (*m_ZFill)(e1.Bot, e1.Top, e2.Bot, e2.Top, pt); 
+  else m_ZFill(e1.Bot, e1.Top, e2.Bot, e2.Top, pt);
 }
 //------------------------------------------------------------------------------
 #endif

src/clipper/clipper.hpp

@@ -35,6 +35,7 @@
 #define clipper_hpp
 
 #include <inttypes.h>
+#include <functional>
 
 #define CLIPPER_VERSION "6.2.6"
 
@@ -56,7 +57,11 @@
 #include <functional>
 #include <queue>
 
+#ifdef use_xyz
+namespace ClipperLib_Z {
+#else /* use_xyz */
 namespace ClipperLib {
+#endif /* use_xyz */
 
 enum ClipType { ctIntersection, ctUnion, ctDifference, ctXor };
 enum PolyType { ptSubject, ptClip };
@@ -114,7 +119,7 @@ struct DoublePoint
 //------------------------------------------------------------------------------
 
 #ifdef use_xyz
-typedef void (*ZFillCallback)(IntPoint& e1bot, IntPoint& e1top, IntPoint& e2bot, IntPoint& e2top, IntPoint& pt);
+typedef std::function<void(const IntPoint& e1bot, const IntPoint& e1top, const IntPoint& e2bot, const IntPoint& e2top, IntPoint& pt)> ZFillCallback;
 #endif
 
 enum InitOptions {ioReverseSolution = 1, ioStrictlySimple = 2, ioPreserveCollinear = 4};

src/clipper/clipper_z.cpp

@@ -0,0 +1,7 @@
+// Hackish wrapper around the ClipperLib library to compile the Clipper library with the Z support.
+
+// Enable the Z coordinate support.
+#define use_xyz
+
+// and let it compile
+#include "clipper.cpp"

src/clipper/clipper_z.hpp

@@ -0,0 +1,18 @@
+// Hackish wrapper around the ClipperLib library to compile the Clipper library with the Z support.
+
+#ifndef clipper_z_hpp
+#ifdef clipper_hpp
+#error "You should include the clipper_z.hpp first"
+#endif
+
+#define clipper_z_hpp
+
+// Enable the Z coordinate support.
+#define use_xyz
+
+#include "clipper.hpp"
+
+#undef clipper_hpp
+#undef use_xyz
+
+#endif clipper_z_hpp