Large-scale Graph Visualisations in the Browser

Nicolas JOSEPH

nicolas@linkurio.us

7 May 2015 | London

Goals

  • You will know why large scale visualizations are importants
  • You will be able to choose wisely between technologies
  • You will be able to solve some challenges raised by graph visualization

Presentation

  • 4 employees
  • Graph visualization software for humans
  • Founded 2013
  • Full stack JavaScript Engineer
  • Worked at the French Departement of Defense
  • Worked at Quandora, NY based start up

Why large scale graph visualization in the Browser?

Why Graph Visualization ?

Jean

Social Security

Number

Melinda

has_number

has_number

Why in the browser ?

  • Cost of deployment and maintenance
  • Javascript Engine performance
  • Enable collaboration through the Web

Why large scale ?

Spot Clusters

 What was on the market

  • Sigma.js
  • Keylines
  • Tom Sawyer
  • Cytoscape
  • Graph Alchemy
  • VivaGraphjs
  • ...

Linkurious.js

Open Source (GPLv3, commercial)

 

Core is sigma.js augmented with multiple plugins

 

Modular Architecture.

Challenges

  1. Display a lot of data
  2. Interact with large graphs
  3. Keep the experience smooth

Large Graphs

1/3

Small

Medium

Large

How can we display display large graph ?

Rendering engines technologies

SVG

Canvas

WebGL

More Built-ins

interactions

Quicker Rendering speed

Linkurious.js

SVG Canvas WebGL
Nodes 500 5 000 20 000
Edges 1 000 8 000 30 000
Speed

Recommended display on an average laptop

Enable Graph interaction

2/3

How is the graph made interactive ?

Basic Solution

Spatial Indexing

Quad Tree

Credits to Berkley

1

2

3

4

1

2

3

4

Graphical Space

Tree Representation

Spatial Indexing

Quad Tree

Credits to Berkley

Graphical Space

Tree Representation

Spatial Indexing

Quad Tree

Credits to Berkley

Graphical Space

Tree Representation

Spatial Indexing

Quad Tree

Credits to Berkley

Graphical Space

Tree Representation

Spatial Indexing

What about Edges ? R-Tree in developement

Rendering engines and built-ins interactions

Technology SVG Canvas WebGL
Built-ins interactions

Keep the UI responsive

3/3

E.g: Linkurious Enterprise

How to keep the interface responsive while computing ?

Use Web Workers

Basic JS

With Web Worker

  • Do This
  • Then do that
  • finally execute this
  • Create Web Worker
  • Do this
  • Do that
  • Receive result

Main Thread 

Web Worker 

  • Do something
  • Compute something
  • Send back result

Layouts

A layout is an algorithm consisting in ordering nodes in a graphical space so that the user can make sense out of its visualization

Force Directed layout

Nodes act as repulsive particles

Edges act as springs

Parallelize Computing

Compute Layout 

Technology Rendering Capabilities Built-in interactions Developer friendly
SVG
Canvas
WebGL

Conclusion

  • Optimise data structure to improve performance
  • Use Web workers for lengthy computations to keep the UI responsive

Thank you

@NicolasJosephIt

Callicles

@

nicolas@linkurio.us

Linkurious.js: 

https://linkurio.us/toolkit

Slides: 

https://slides.com/nicolasjoseph/largescalevis

Download for free

Spatial Indexing

R - Tree

Large Graph Visualizations on the Web

By Nicolas Joseph

Large Graph Visualizations on the Web

This slides were presented during GraphConnect 2015 in London. The main goals of this presentation were: - Give the audience tools to choose a graph visualization library - Present some challenges that can be faced doing graph visualization and how to solve them.

  • 2,793
Loading comments...

More from Nicolas Joseph