Geom Software - C++ Programming and Geometry Libraries
Fade2D Documentation pages v1.37
Delaunay Triangulation Library for C++ - Download

Introduction to Fade2D

  • Fade is among the fastest Delaunay triangulation libraries for C++
  • Free for scientific research. Commercial licenses and support are available
  • Polygon support
  • Mesh generator
  • Constrained Delaunay, Conforming Delaunay
  • Easy to use and well documented
  • Numerically robust
  • Classic 2D version and extended 2.5D version for height fields

Delaunay triangulation with Fade2D

Delaunay triangulation 2D

Constrained Delaunay triangulation

Constrained Delaunay triangulation

Zones in a triangulation

Zones in a triangulation

2D mesh generation

2D Mesh generation

Getting started

Download. Unzip. Start to play with the included examples. It works without installation for Windows and Linux developers.

Fade2D and Fade2.5D are two separate libraries. Fade2.5D uses Fade2D as code base. Thus the methods from Fade2D are also available in Fade2.5D and the look and feel of the two libraries is very similar. The namespaces are different (GEOM_FADE2D vs. GEOM_FADE25D) and Fade2.5D features methods which are not contained in Fade2D. Thus there are two separate documentations.

Documentation Download
Fade 2D HTML (this document) PDF Download Fade2D and Fade2.5D v1.37
Fade 2.5D HTML PDF

Directory Contents

  • include_fade2d and include_fade25d
    Header files of the two libraries.
  • Win32 and x64
    This directory contains the DLL's for Windows 32-bit and 64-bit and it is the target directory for the executables of example code compiled with Visual Studio.
    The shared libs (*.so) for Linux developers.
  • examples_2D
    Example source code and Visual Studio projects using Fade2D
  • examples_25D
    Example source code and Visual Studio projects using Fade2.5D
  • doc

For Windows users:

  1. Open one of the Visual Studio example projects (currently supported: vs2008, vs2010, vs2012, vs2013, vs2015)
  2. Compile the example source code. The executable is written to the Win32 or x64 folder.

For Linux users:

  1. Make sure GMP is installed:
    $ sudo apt-get install libgmp10 (works on Ubuntu/Debian/Mint, on other systems search for gmp)
  2. Enter an example directory, choose your Linux distribution in the Makefile and type make to compile the source code.

Work through the provided examples. They are small, well documented and they visualize the results.


  • Mixing multiple Visual Studio versions is not recommended.
  • Make sure that the right *.dll is used in your project.
  • Compare your settings with the ones from the example projects.

If your problem persists, don't hesitate to send a minimal example that reproduces it and it will be fixed asap.

Release notes / History

Version 1.37, March 10th, 2016:
Interface change in the MeshGenParams class. The class has been introduced two weeks before, so chances are good that the change does not affect you. Previously the class had the methods getMaxTriangleArea(double x,double y) and getMaxEdgeLength(double x,double y) where x and y where the barycenter of a triangle for which the algorithm determines if it must be refined. The change is that x and y have been replaced by the triangle itself to give client code even more control (x and y can still be computed from the triangle).

Version 1.36, February 29th, 2016:
Experimental method refineExtended(..) replaced by the (now permanent) method refineAdvanced(MeshGenParams* pParams). This method allows much more control over the mesh density.

Version 1.34, February 14th, 2016:
Vertex management subsystem revised (sometimes Vertex removement did not work as expected). Performance improvement.

Version 1.33 PreRelease, January 17th, 2016:
The previous official Fade version is Fade 1.24. It was released 6 months ago. Since then major developments have been made and now a big upgrade follows with version 1.33.14: Constraint segments may intersect now and they are automatically subdivided at their intersection points. Import of existing triangles is supported and one can cut through static triangulations. This version is well tested. It also runs at two customers sites with no known problems. But due to the large amount of new code we call this version a pre-release. Please report if you find any problems and note that it is also helpful if you report that the library works well in your setting. The DLL names have been adapted to the safer and more convenient pattern


If you upgrade from an earlier version it is recommended that you remove any previous Fade DLL's to avoid unintended linking to an old version.

Version 1.31 and 1.32, December 1st, 2015:
Non public intermediate release, improves the CDT.

Version 1.30, November 18th, 2015:
Non public intermediate release, improves the refineExtended method.

Version 1.29, October 17th, 2015:
Non public intermediate release. The method importTriangles() detects invalid input data now and returns NULL to avoid an assertion or even an infinite loop when the input data is not clean. The possibly invalid input elements are written to stdout and a postscript file visualizes where the problem occurs.

Version 1.28, October 10th, 2015:
Non public intermediate release. Customer specific code revised. Stress tests with random polygons and segments have been made. Heap checking to ensure proper memory handling.

Version 1.27, October 5th, 2015:
Non public release, improvements of the recently implemented functions, especially of customer specific code Fade_2D::importTriangles() and Fade2D::cutTriangles().

Version 1.26, September 8th, 2015:
New functions of the last inofficial version 1.25 have been revised. Constraint segments may intersect now.

Version 1.25, August 18th, 2015:
Intermediate pre-release with new features: importTriangles() imports arbitrary triangles into a triangulation, cutTriangles() allows to insert a constraint segment as if it where a knife, getOrientation() provides an exact orientation test. Zone2 objects can now also be made from a set of triangles. Constraint segments can intersect now. These features correspond to a large amount of new code: Please test v1.25 carefully before deploying it in a production environment.

Version 1.24, July 22nd, 2015:
Public release of version 1.23's improvements. And I'm sorry but we had a bug in Fade_2D::getVertexPointers(..). The method may have missed to return a few pointers after a call to refine() or remove(). This bug is fixed now.

Version 1.23, July 9th, 2015:
Internal test release with the new refineExtended() method for the specific needs of a certain client software.

Version 1.22, May 25th, 2015:
Code refactored, build system refactored and as a result improved Linux support: CentOS 6.4, Ubuntu 14.04, Ubuntu 15.04 and similar systems. Removement of points has been implemented, Delaunay meshing has been reworked, sqDistance() has been replaced by sqDistance2D() and sqDistance25D() because both versions are useful in 2.5D. OpenMP has been removed, it was only used under Linux and currently I work on a better way to provide multithreading.

Version 1.21, May 17th, 2015:
Unofficial intermediate release. Testing new features.

Version 1.20, April 5th, 2015:
3D scene Visualization for (up to date) web browsers added. Misleading enumeration values CIS_KEEP_DELAUNAY and CIS_IGNORE_DELAUNAY have been replaced by CIS_CONFORMING_DELAUNAY and CIS_CONSTRAINED_DELAUNAY (the two deprecated names are kept for backward compatibility). Bug in the free function center(Point2&,Point2&) solved. Major revision of the documentation pages. The source codes of the examples have been reengineered and are included in the present documentation pages.

Version 1.19, October 26th, 2014:
Support for Visual Studio 2013 (VC12) has been added. Only minor code changes.

Version 1.18.3, June 9th, 2014:
Delaunay Mesh Generation has been improved: Better quality, better performance. API improved. Small bug fixes.

Version 1.16.1, February 10th, 2014:
Small update: In rare cases it was possible that subdivided ConstraintSegments caused problems in combination with zone growing. This is fixed now.

Version 1.16, February 3rd, 2014:
Constrained Delaunay triangulation improved, Delaunay meshing improved, aspect ratio meshing (experimental) added. Minor bug fixes. Added support for Visual Studio 2012.

Version 1.14, November 2013 and version 1.15, December 2013:
Non-public intermediate releases (test versions with experimental features).

Version 1.13, August 4th, 2013:
Mesh generation (Delaunay Meshing) has been improved and two bugfixes have been made in the new IsoContours class: A message can be suppressed now and a numeric problem has been fixed.

Version 1.12, June 30th, 2013:
Starting with version v1.12 the download consists of two separate libraries: The familiar full version of the 2D flavor as well as a 2.5D evaluation version. Two very fast new methods have been added to the 2.5D version: One computes iso-contours, the other computes the height of a point with arbitrary (x,y) coordinates. Delaunay mesh generation has been improved. Support for VS2008, 32-bit and 64-bit, has been added. The performance has been improved.

Version 1.11, June 14th, 2013:
Non-public intermediate release with VS2008 support and a first version of the iso-contour feature.

Version 1.10, March 30th, 2013:
Delaunay Refinement (already included as preview in the previous release) has been improved and is officially released now. Parts of the algorithm can use up to 8 CPUs under Linux if explicitly switched on using Fade2D::enableMultithreading(). There is a new insert method in the API which uses arrays.

Version 1.03, Nov. 4th, 2012:
A critical bug has been fixed, please switch to the current version. Performance upgrade: A first step towards multithreading has been made in the Linux version. In order to facilitate the installation for users without administrator privileges the installers have been replaced by a simple zipped directory that contains everything. Meshing through Delaunay Refinement is scheduled for the next release but it is pre-released as an experimental feature in the current version 1.03.

Version 1.02, 9/2012:
An additional debug library version for Windows has been added and the directory structure has been reorganized.

Version 1.01, 9/2012:
This is a stable public release. Since version 0.9 we have introduced insertion of constraint edges and the zone concept. Moreover the API is under a namespace now. Boost types have been removed from the API to avoid this additional dependency. New demo software has been written and the library is now also available for 64-bit Windows.