Libraries for constraint-based layout and connector routing for diagrams.
C++ C Java Makefile Prolog Mathematica


Adaptagrams is a library of tools and reusable code for adaptive diagramming applications, for example: drawing tools, automated document and diagram layout, smart presentation software, graph drawing, chart layout, etc.

Currently, the Adaptagrams repository includes four cross-platform C++ libraries:

  • libvpsc
    - a solver for the Variable Placement with Separation Constraints problem. This is a quadratic programming problem in which the squared differences between a placement vector and some ideal placement are minimised subject to a set of separation constraints. This is very useful in a number of layout problems.
  • libcola
    - a library for constraint graph layout. Specifically, force-directed layout using the stress-majorization method subject to separation constraints. Applications include layout with non-overlapping nodes and clusters, directed graph layout and layout preserving the crossing properties of a given starting layout.
    - libcola depends on libvpsc.
  • libavoid
    - a library providing high-quality object-avoiding polyline and orthogonal connector routing for use in interactive diagram editors.
  • libtopology
    - a library containing extensions to libcola to support topology preserving constraint-based layout.
    - libtopology depends on libavoid, libcola and libvpsc.

These libraries are collectively known as cola (for Constraint Layout). The newest version of the C++ source code for cola can be found in the Adaptagrams github repository maintaied by Michael Wybrow:

All code in the Adaptagrams repository is released as open source under the terms of the LGPL 2.1 or later, see the LICENSE file.

We also dual-license the Adaptagrams libraries and for a fee we can provide them under a less-restrictive commercial license as well as extend them to fit your needs (contact us). For this reason, if you contribute code to the project and would like it to appear in the main Adaptagrams repository, we require that you assign the copyright on your changes to Monash Univeristy with the following statement: "I hereby assign copyright in this code to Monash University, to be licensed under the same terms as the rest of the code."

Software using one or more of the Adaptagrams libraries include:

  • Dunnart, constraint-based diagram editor,
  • Inkscape, the popular open source vector graphics editor,
  • Graphviz, open source graph visualisation software,
  • Arcadia, a visualisation tool for metabolic pathways,
  • Gaphas, an open source Python-based diagramming widget for GTK+, and
  • BRL-CAD, a powerful cross-platform open source solid modeling system that includes interactive geometry editing, high-performance ray-tracing for rendering and geometric analysis, image and signal-processing tools, a system performance analysis benchmark suite, libraries for robust geometric representation, with more than 20 years of active development.

The algorithms were developed by members of the MArVL: Monash Adaptive Visualisation Lab at Monash University in Melbourne, Australia. The Adaptagrams libraries were originally written by Tim Dwyer and Michael Wybrow.


The library code is all contained in the cola directory of the repository.

We use GNU automake to build. We've tried to make the contents of the repository as platform agnostic as possible, so you'll need to call aclocal, autoconf, and automake before configure.

The only dependency is Cairo if debugging SVG output is to be included in several example test cases. The libraries themselves have no dependencies.

Run ./ to compile from scratch.

Use from other languages

Bindings for use of the Adaptagrams libraries can be generated using SWIG. The repository contains a SWIG interface file cola/adaptagrams.i. We have successfully tested and used Adaptagrams from Java and Python in this way.

Cola in the browser

cola.js (a.k.a. WebCola) is a JavaScript based rewrite of libcola which works well with D3.js