Clipper2

A Polygon Clipping, Offsetting and Triangulation library (in C++, C# & Delphi)

  

The Clipper2 library performs intersection, union, difference and XOR boolean operations on both simple and complex polygons. It also performs polygon offsetting, and Constrained Delaunay Triangulation. This is a major update of my original Clipper library that was written over 10 years ago. That library I'm now calling Clipper1, and while it still works very well, Clipper2 is better in just about every way.

Compilers

Clipper2 can be compiled using either C++, or C#, or Delphi Pascal. The library can also be accessed from other programming languages by dynamically linking to exported functions in the C++ compiled Clipper2 library. (Since the C++ compiled code is measurably faster, C# and Delphi developers may also prefer this approach in applications where the library's performance is critical.)

Lang.	Requirements
C++:	Requires C++17, or
C#:	The library uses Standard Library 2.0 but the sample code uses .NET6, or
Delphi:	Compiles with any version of Delphi from version 7 to current.

Documentation

Extensive HTML documentation

Examples

Clipping

      //C++
      Paths64 subject, clip, solution;
      subject.push_back(MakePath({100, 50, 10, 79, 65, 2, 65, 98, 10, 21}));
      clip.push_back(MakePath({98, 63, 4, 68, 77, 8, 52, 100, 19, 12}));
      solution = Intersect(subject, clip, FillRule::NonZero);

      //C#
      Paths64 subj = new Paths64();
      Paths64 clip = new Paths64();
      subj.Add(Clipper.MakePath(new int[] { 100, 50, 10, 79, 65, 2, 65, 98, 10, 21 }));
      clip.Add(Clipper.MakePath(new int[] { 98, 63, 4, 68, 77, 8, 52, 100, 19, 12 }));
      Paths64 solution = Clipper.Intersect(subj, clip, FillRule.NonZero);

      //Delphi
      var 
        subject, clip, solution: TPaths64;
      begin
        SetLength(subject, 1);
        subject[0] := MakePath([100, 50, 10, 79, 65, 2, 65, 98, 10, 21]);
        SetLength(clip, 1);
        clip[0] := MakePath([98, 63, 4, 68, 77, 8, 52, 100, 19, 12]);
        solution := Intersect( subject, clip, frNonZero);

Constrained Delaunay Triangulation

C++

Clipper2/CPP/Examples/Triangulation/Triangulation.cpp

Lines 247 to 249 in 01bacc0

	subject = GetPathsFromSvgFile(folder + "coral3.svg");
	Triangulate(subject, 0, sol, true);
	DisplaySolution(".\\coral3t.svg", sol, multicolor);

C#

Clipper2/CSharp/Clipper2Lib.Examples/Triangulation/Main.cs

Lines 257 to 261 in 01bacc0

	string TestFile = "coral3.svg";
	srcFile = svgFolder + TestFile;
	subject = GetPathsFromSvgFile(srcFile);
	if (Clipper.Triangulate(subject, 0, out solution) == TriangulateResult.success)
	Display(solution, tmpFolder + TestFile);

Delphi

Clipper2/Delphi/Examples/Triangulation/ClipperTri.dpr

Lines 216 to 224 in 0a9f445

	inFilename := svgFolder + 'coral3.svg';
	if not FileExists(inFilename) then Exit;
	outFilename := 'coral3t.svg';
	pp := GetPathsFromSvgFile(inFilename);
	if Triangulate(pp, 0, sol, true) = trSuccess then
	begin
	SavePathsAsSvg(outFilename, pp, sol, rfOverwrite, false);
	ShellExecute(0, nil, PChar(outFilename), nil, nil, 0);
	end;

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Ports to other languages

lang.	link
Java	https://github.com/micycle1/Clipper2-java/
TypeScript	https://github.com/countertype/clipper2-ts
Kotlin	https://github.com/Monkey-Maestro/clipper2-kotlin
golang	https://github.com/epit3d/goclipper2
Lua	https://github.com/Ark223/Clipper2-Lua
WASM	https://github.com/ErikSom/Clipper2-WASM/