Update to Clipper2 (openscad#5501)

* Add Clipper2 as submodule, update manifold
* Port to Clipper2

.gitmodules

@@ -6,10 +6,13 @@
 	url = https://github.com/microsoft/mimalloc.git
 [submodule "submodules/manifold"]
 	path = submodules/manifold
-	url = https://github.com/elalish/manifold
+	url = https://github.com/elalish/manifold.git
 [submodule "sanitizers-cmake"]
 	path = submodules/sanitizers-cmake
 	url = https://github.com/arsenm/sanitizers-cmake.git
 [submodule "OpenCSG"]
 	path = submodules/OpenCSG
 	url = https://github.com/openscad/OpenCSG.git
+[submodule "Clipper2"]
+	path = submodules/Clipper2
+	url = https://github.com/AngusJohnson/Clipper2.git

CMakeLists.txt

@@ -33,6 +33,7 @@ option(ENABLE_TESTS "Run testsuite after building." ON)
 option(EXPERIMENTAL "Enable Experimental Features" OFF)
 option(USE_MANIFOLD_TRIANGULATOR "Use Manifold's triangulator instead of CGAL's" ON)
 option(USE_BUILTIN_MANIFOLD "Use manifold from submodule" ON)
+option(USE_BUILTIN_CLIPPER2 "Use Clipper2 from submodule" ON)
 option(USE_LEGACY_RENDERERS "Use legacy (non-VBO) OpenGL renderers" OFF)
 option(SNAPSHOT "Create dev snapshot, uses nightly icons" OFF)
 option(HEADLESS "Build without GUI frontend" OFF)
@@ -846,7 +847,6 @@ set(CORE_SOURCES
   src/ext/libtess2/Source/sweep.c
   src/ext/libtess2/Source/tess.c
   src/ext/lodepng/lodepng.cpp
-  src/ext/polyclipping/clipper.cpp
   src/geometry/ClipperUtils.cc
   src/geometry/Geometry.cc
   src/geometry/GeometryCache.cc
@@ -968,6 +968,19 @@ set(MANIFOLD_CGAL_SOURCES
   src/geometry/manifold/manifold-applyops-minkowski.cc
 )
 
+if(USE_BUILTIN_CLIPPER2)
+  set(CLIPPER2_UTILS OFF)
+  set(CLIPPER2_EXAMPLES OFF)
+  set(CLIPPER2_TESTS OFF)
+  add_subdirectory("submodules/Clipper2/CPP" EXCLUDE_FROM_ALL)
+  set(Clipper2_FOUND "YES")
+  message(STATUS "Clipper2 submodule")
+else()
+  find_package(Clipper2 REQUIRED QUIET)
+  message(STATUS "Clipper2: ${Clipper2_VERSION}")
+endif()
+target_link_libraries(OpenSCAD PRIVATE Clipper2::Clipper2)
+
 if(ENABLE_MANIFOLD)
   if(NOT DEFINED MANIFOLD_PAR)
     # Note: currently only Manifold-related code makes use of TBB parallelization
@@ -1225,11 +1238,6 @@ set(GUI_UIS
     src/gui/parameter/ParameterWidget.ui
 )
 
-if("${CMAKE_CXX_COMPILER_ID}" STREQUAL "GNU")
-  # Ignore specific warning on external lib
-  set_source_files_properties("src/ext/polyclipping/clipper.cpp" PROPERTIES COMPILE_FLAGS "-Wno-class-memaccess")
-endif()
-
 if (ENABLE_MANIFOLD)
   target_compile_definitions(OpenSCAD PRIVATE ENABLE_MANIFOLD)
   list(APPEND Sources ${MANIFOLD_SOURCES})

src/core/OffsetNode.cc

@@ -32,6 +32,7 @@
 #include "core/Parameters.h"
 #include "core/Builtins.h"
 
+#include <clipper2/clipper.offset.h>
 #include <ios>
 #include <utility>
 #include <memory>
@@ -53,15 +54,15 @@ static std::shared_ptr<AbstractNode> builtin_offset(const ModuleInstantiation *i
   // radius takes precedence if both r and delta are given.
   node->delta = 1;
   node->chamfer = false;
-  node->join_type = ClipperLib::jtRound;
+  node->join_type = Clipper2Lib::JoinType::Round;
   if (parameters["r"].isDefinedAs(Value::Type::NUMBER)) {
     node->delta = parameters["r"].toDouble();
   } else if (parameters["delta"].isDefinedAs(Value::Type::NUMBER)) {
     node->delta = parameters["delta"].toDouble();
-    node->join_type = ClipperLib::jtMiter;
+    node->join_type = Clipper2Lib::JoinType::Miter;
     if (parameters["chamfer"].isDefinedAs(Value::Type::BOOL) && parameters["chamfer"].toBool()) {
       node->chamfer = true;
-      node->join_type = ClipperLib::jtSquare;
+      node->join_type = Clipper2Lib::JoinType::Square;
     }
   }
 
@@ -72,7 +73,7 @@ std::string OffsetNode::toString() const
 {
   std::ostringstream stream;
 
-  bool isRadius = this->join_type == ClipperLib::jtRound;
+  bool isRadius = this->join_type == Clipper2Lib::JoinType::Round;
   auto var = isRadius ? "(r = " : "(delta = ";
 
   stream << this->name() << var << std::dec << this->delta;

src/core/OffsetNode.h

@@ -1,7 +1,7 @@
 #pragma once
 
 #include "core/node.h"
-#include "polyclipping/clipper.hpp"
+#include "clipper2/clipper.h"
 
 #include <string>
 
@@ -16,5 +16,5 @@ class OffsetNode : public AbstractPolyNode
   bool chamfer{false};
   double fn{0}, fs{0}, fa{0}, delta{1};
   double miter_limit{1000000.0}; // currently fixed high value to disable chamfers with jtMiter
-  ClipperLib::JoinType join_type{ClipperLib::jtRound};
+  Clipper2Lib::JoinType join_type{Clipper2Lib::JoinType::Round};
 };

src/core/TextNode.cc

@@ -66,7 +66,7 @@ static std::shared_ptr<AbstractNode> builtin_text(const ModuleInstantiation *ins
   return node;
 }
 
-std::vector<std::shared_ptr<const Polygon2d>> TextNode::createGeometryList() const
+std::vector<std::shared_ptr<const Polygon2d>> TextNode::createPolygonList() const
 {
   FreetypeRenderer renderer;
   return renderer.render(this->get_params());

src/core/TextNode.h

@@ -19,7 +19,7 @@ class TextNode : public AbstractPolyNode
   std::string toString() const override;
   std::string name() const override { return "text"; }
 
-  std::vector<std::shared_ptr<const Polygon2d>> createGeometryList() const;
+  std::vector<std::shared_ptr<const Polygon2d>> createPolygonList() const;
 
   virtual FreetypeRenderer::Params get_params() const;