TALA Autolayout Algorithm for Diagramming is Now Open-Source Under MPL-2.0 License

TALA Released as Open-Source

Terrastruct's AutoLayout Algorithm (TALA), a specialized autolayout engine for software architecture diagrams, has been made open-source. The algorithm is now available under the Mozilla Public License 2.0 (MPL-2.0), the same license used by D2, a diagramming language.

Orthogonal Layout for Aesthetic Diagrams

TALA functions as an orthogonal layout engine, differing from common DAG-based algorithms that grow in one direction. It integrates concepts from various graph-drawing research papers and original techniques to produce aesthetically pleasing diagrams. The algorithm considers multiple aesthetic objectives, including symmetry, median distance, flow, and clustering of similar nodes.

Key Features and Customization

TALA allows for customization of node positions and sizes, enabling users to lock coordinates for specific nodes while the engine handles routing for others. This feature is particularly useful for scenarios where models generate 2D layouts but require assistance with connection routing. Examples demonstrate TALA's ability to combine user-specified coordinates with automatic layout for the remaining elements.

Trade-offs and Performance

TALA has certain trade-offs, including a degree of randomness in its algorithm, which can lead to different layouts when a single node is added. It may not perform as well for long, flowing directed acyclic graphs (DAGs) compared to alternatives like Dagre or ELK. Additionally, TALA's runtime can increase nonlinearly for larger diagrams. Benchmarks comparing TALA's performance to other algorithms are available on GitHub.

TALA is included in D2 v0.9.0; users can activate it by specifying "--layout=tala" when generating diagrams.