Fixed open path clipping issue (#60)

Fixed crash dereferencing a null pointer (#59)
Numerous other minor tweaks

CPP/Clipper2Lib/clipper.engine.h

@@ -1,7 +1,7 @@
 /*******************************************************************************
 * Author    :  Angus Johnson                                                   *
 * Version   :  10.0 (beta) - aka Clipper2                                      *
-* Date      :  18 May 2022                                                     *
+* Date      :  22 May 2022                                                     *
 * Website   :  http://www.angusj.com                                           *
 * Copyright :  Angus Johnson 2010-2022                                         *
 * Purpose   :  This is the main polygon clipping module                        *
@@ -55,17 +55,17 @@ namespace Clipper2Lib {
 
 	struct Vertex {
 		Point64 pt;
-		Vertex* next = NULL;
-		Vertex* prev = NULL;
+		Vertex* next = nullptr;
+		Vertex* prev = nullptr;
 		VertexFlags flags = VertexFlags::None;
 	};
 
 	struct OutPt {
 		Point64 pt;
-		OutPt*	next = NULL;
-		OutPt*	prev = NULL;
+		OutPt*	next = nullptr;
+		OutPt*	prev = nullptr;
 		OutRec* outrec;
-		Joiner* joiner = NULL;
+		Joiner* joiner = nullptr;
 
 		OutPt(const Point64& pt_, OutRec* outrec_): pt(pt_), outrec(outrec_) {
 			next = this;
@@ -86,12 +86,12 @@ namespace Clipper2Lib {
 	//OutRec: contains a path in the clipping solution. Edges in the AEL will
 	//have OutRec pointers assigned when they form part of the clipping solution.
 	struct OutRec {
-		size_t idx;
-		OutRec* owner;
-		Active* front_edge;
-		Active* back_edge;
-		OutPt* pts;
-		PolyPath64* polypath = NULL;
+		size_t idx = 0;
+		OutRec* owner = nullptr;
+		Active* front_edge = nullptr;
+		Active* back_edge = nullptr;
+		OutPt* pts = nullptr;
+		PolyPath64* polypath = nullptr;
 		OutRecState state = OutRecState::Undefined;
 	};
 
@@ -103,21 +103,21 @@ namespace Clipper2Lib {
 		int wind_dx = 1;			//1 or -1 depending on winding diRect64on
 		int wind_cnt = 0;
 		int wind_cnt2 = 0;		//winding count of the opposite polytype
-		OutRec* outrec = NULL;
+		OutRec* outrec = nullptr;
 		//AEL: 'active edge list' (Vatti's AET - active edge table)
 		//     a linked list of all edges (from left to right) that are present
 		//     (or 'active') within the current scanbeam (a horizontal 'beam' that
 		//     sweeps from bottom to top over the paths in the clipping operation).
-		Active* prev_in_ael = NULL;
-		Active* next_in_ael = NULL;
+		Active* prev_in_ael = nullptr;
+		Active* next_in_ael = nullptr;
 		//SEL: 'sorted edge list' (Vatti's ST - sorted table)
 		//     linked list used when sorting edges into their new positions at the
 		//     top of scanbeams, but also (re)used to process horizontals.
-		Active* prev_in_sel = NULL;
-		Active* next_in_sel = NULL;
-		Active* jump = NULL;
-		Vertex* vertex_top = NULL;
-		LocalMinima* local_min = NULL;  //the bottom of an edge 'bound' (also Vatti)
+		Active* prev_in_sel = nullptr;
+		Active* next_in_sel = nullptr;
+		Active* jump = nullptr;
+		Vertex* vertex_top = nullptr;
+		LocalMinima* local_min = nullptr;  //the bottom of an edge 'bound' (also Vatti)
 		bool is_left_bound = false;
 	};
 
@@ -144,9 +144,9 @@ namespace Clipper2Lib {
 		bool error_found_ = false;
 		bool has_open_paths_ = false;
 		bool minima_list_sorted_ = false;
-		Active *actives_ = NULL;
-		Active *sel_ = NULL;
-		Joiner *horz_joiners_ = NULL;
+		Active *actives_ = nullptr;
+		Active *sel_ = nullptr;
+		Joiner *horz_joiners_ = nullptr;
 		std::vector<LocalMinima*> minima_list_;
 		std::vector<LocalMinima*>::iterator loc_min_iter_;
 		std::vector<Vertex*> vertex_lists_;
@@ -235,7 +235,7 @@ namespace Clipper2Lib {
 		bool PreserveCollinear = true;
 		void Clear();
 #ifdef USINGZ
-		ClipperBase() { zfill_func_ = NULL; };
+		ClipperBase() { zfill_func_ = nullptr; };
 		void ZFillFunction(ZFillCallback zFillFunc);
 #else
 		ClipperBase() {};
@@ -265,7 +265,7 @@ namespace Clipper2Lib {
 		explicit PolyPath(int precision = 0) //NB only for root node
 		{  
 			scale_ = std::pow(10, precision);
-			parent_ = NULL;
+			parent_ = nullptr;
 		}
 
 		virtual ~PolyPath() { Clear(); };

CPP/Examples/ConsoleDemo1/ConsoleDemo1.cpp

@@ -5,6 +5,7 @@
 #include "../../Clipper2Lib/clipper.h"
 #include "../../Utils/clipper.svg.utils.h"
 #include "../../Utils/ClipFileLoad.h"
+#include "../../Utils/ClipFileSave.h"
 #include "../../Utils/Timer.h"
 
 using namespace Clipper2Lib;
@@ -38,7 +39,7 @@ int main()
     if (test_type == TestType::Simple) break;
 
   case TestType::SavedTests:
-    RunSavedTests("../../../Tests/tests.txt", 1, 200, false, false);
+    RunSavedTests("../../../Tests/tests.txt", 1, 0xFFFF, false, false);
     //or test just one of the samples in tests.txt 
     //DoTestsFromFile("../../Tests/tests.txt", 16, 16, true, true);
     if (test_type == TestType::SavedTests) break;
@@ -58,8 +59,9 @@ int main()
 
   std::cout << std::endl;
 #ifdef _DEBUG
-  //std::cout << "Press any key to continue" << std::endl;
-  //const char c = _getch();
+  std::string s;
+  std::cout << "Press Enter to continue" << std::endl;
+  std::getline(std::cin, s);
 #endif
   return 0;
 }
@@ -132,7 +134,9 @@ void DoSimpleTest(bool show_solution_coords)
 
   Paths64 subject, clip;
   subject.push_back(MakeStar(Point64(225, 225), 220, 9));
-  clip.push_back(Ellipse<int64_t>(Point64(225,225), 150, 150));
+  clip.push_back(Ellipse<int64_t>(Point64(225,225), 150, 150));  
+  //SaveTest("debug.txt", false, &subject, NULL, &clip, 0, 0, ClipType::Intersection, fr);
+
   //Intersect both shapes and then 'inflate' result -10 (ie deflate)
   solution = Intersect(subject, clip, fr);
   solution = InflatePaths(solution, -10, JoinType::Round, EndType::Polygon);
@@ -175,11 +179,11 @@ void RunSavedTests(const std::string& filename,
       int64_t count2 = solution.size();
       int64_t count_diff = abs(count2 - count);
       if (count && count_diff > 2 && count_diff/ static_cast<double>(count) > 0.02)
-        std::cout << "  Test " << i << " counts differ: Saved val= " <<
+        std::cout << "  Test " << i << " path counts differ: Saved val= " <<
         count << "; New val=" << count2 << std::endl;
       int64_t area_diff = std::abs(area2 - area);
       if (area && (area_diff > 2) && (area_diff/static_cast<double>(area)) > 0.02)
-        std::cout << "  Test " << i << " areas differ: Saved val= " <<
+        std::cout << "  Test " << i << " path areas differ: Saved val= " <<
         area << "; New val=" << area2 << std::endl;
       if (svg_draw)
       {

CPP/Utils/ClipFileLoad.cpp

@@ -64,6 +64,7 @@ bool LoadTestNum(ifstream &source, int test_num, bool seek_from_start,
   int64_t& area, int64_t& count, ClipType &ct, FillRule &fr)
 {
   string line;
+  area = 0; count = 0;
   bool found = false;
   if (seek_from_start) source.seekg(0, ios_base::beg);
   stringstream::pos_type last_read_line_pos = source.tellg();

CPP/Utils/ClipFileSave.cpp

@@ -224,7 +224,7 @@ void PathsToStream(Paths64& paths, std::ostream& stream)
 }
 
 bool SaveTest(const std::string& filename, bool append,
-  Clipper2Lib::Paths64& subj, Clipper2Lib::Paths64& subj_open, Clipper2Lib::Paths64& clip,
+  Clipper2Lib::Paths64* subj, Clipper2Lib::Paths64* subj_open, Clipper2Lib::Paths64* clip,
   int64_t area, int64_t count, Clipper2Lib::ClipType ct, Clipper2Lib::FillRule fr)
 {
   string line;
@@ -280,12 +280,20 @@ bool SaveTest(const std::string& filename, bool append,
   source << "FILLRULE: " << fillrule_string << endl;
   source << "SOL_AREA: " << area << endl;
   source << "SOL_COUNT: " << count << endl;
-  source << "SUBJECTS" << endl;
-  PathsToStream(subj, source);
-  if (clip.size())
+  if (subj)
+  {
+    source << "SUBJECTS" << endl;
+    PathsToStream(*subj, source);
+  }
+  if (subj_open)
+  {
+    source << "SUBJECTS_OPEN" << endl;
+    PathsToStream(*subj_open, source);
+  }
+  if (clip && clip->size())
   {
     source << "CLIPS" << endl;
-    PathsToStream(clip, source);
+    PathsToStream(*clip, source);
   }
   source << endl;
   source.close();

CPP/Utils/ClipFileSave.h

@@ -8,7 +8,7 @@
 #include "../Clipper2Lib/clipper.h"
 
 bool SaveTest(const std::string& filename, bool append,
-  Clipper2Lib::Paths64& subj, Clipper2Lib::Paths64& subj_open, Clipper2Lib::Paths64& clip,
+  Clipper2Lib::Paths64* subj, Clipper2Lib::Paths64* subj_open, Clipper2Lib::Paths64* clip,
   int64_t area, int64_t count, Clipper2Lib::ClipType ct, Clipper2Lib::FillRule fr);
 
 #endif //CLIPPER_TEST_SAVE_H

CSharp/Clipper2Lib.sln

@@ -12,7 +12,11 @@ Project("{2150E333-8FDC-42A3-9474-1A3956D46DE8}") = "Solution Items", "Solution
 		.editorconfig = .editorconfig
 	EndProjectSection
 EndProject
-Project("{FAE04EC0-301F-11D3-BF4B-00C04F79EFBC}") = "ConsoleDemo", "Clipper2LibExamples\ConsoleDemo\ConsoleDemo.csproj", "{9D72A42C-E1B0-4E7A-B3B4-62C0AA02E5A7}"
+Project("{9A19103F-16F7-4668-BE54-9A1E7A4F7556}") = "ConsoleDemo", "Clipper2LibExamples\ConsoleDemo\ConsoleDemo.csproj", "{9D72A42C-E1B0-4E7A-B3B4-62C0AA02E5A7}"
+EndProject
+Project("{9A19103F-16F7-4668-BE54-9A1E7A4F7556}") = "Clipper2.SVG", "Utils\SVG\Clipper2.SVG.csproj", "{BC8E75BA-24E1-4D6A-AE54-0B1019C18EFE}"
+EndProject
+Project("{9A19103F-16F7-4668-BE54-9A1E7A4F7556}") = "Clipper.FileIO.", "Utils\ClipFileIO\Clipper.FileIO..csproj", "{2EF8FB02-E3F6-46CE-954F-5E1B0AD64DB7}"
 EndProject
 Global
 	GlobalSection(SolutionConfigurationPlatforms) = preSolution
@@ -32,6 +36,14 @@ Global
 		{9D72A42C-E1B0-4E7A-B3B4-62C0AA02E5A7}.Debug|Any CPU.Build.0 = Debug|Any CPU
 		{9D72A42C-E1B0-4E7A-B3B4-62C0AA02E5A7}.Release|Any CPU.ActiveCfg = Release|Any CPU
 		{9D72A42C-E1B0-4E7A-B3B4-62C0AA02E5A7}.Release|Any CPU.Build.0 = Release|Any CPU
+		{BC8E75BA-24E1-4D6A-AE54-0B1019C18EFE}.Debug|Any CPU.ActiveCfg = Debug|Any CPU
+		{BC8E75BA-24E1-4D6A-AE54-0B1019C18EFE}.Debug|Any CPU.Build.0 = Debug|Any CPU
+		{BC8E75BA-24E1-4D6A-AE54-0B1019C18EFE}.Release|Any CPU.ActiveCfg = Release|Any CPU
+		{BC8E75BA-24E1-4D6A-AE54-0B1019C18EFE}.Release|Any CPU.Build.0 = Release|Any CPU
+		{2EF8FB02-E3F6-46CE-954F-5E1B0AD64DB7}.Debug|Any CPU.ActiveCfg = Debug|Any CPU
+		{2EF8FB02-E3F6-46CE-954F-5E1B0AD64DB7}.Debug|Any CPU.Build.0 = Debug|Any CPU
+		{2EF8FB02-E3F6-46CE-954F-5E1B0AD64DB7}.Release|Any CPU.ActiveCfg = Release|Any CPU
+		{2EF8FB02-E3F6-46CE-954F-5E1B0AD64DB7}.Release|Any CPU.Build.0 = Release|Any CPU
 	EndGlobalSection
 	GlobalSection(SolutionProperties) = preSolution
 		HideSolutionNode = FALSE