Animated Vega-Lite: Unifying Animation with a Grammar of Interactive Graphics.

Area of Science:

• Computer Science
• Data Visualization

Background:

• Existing animated visualization systems often prioritize expressiveness over integration with static and interactive designs.
• Seamlessly combining static, interactive, and animated visualizations presents a significant challenge in data visualization language design.

Purpose of the Study:

• To introduce Animated Vega-Lite, a novel extension to Vega-Lite for modeling animated visualizations.
• To unify animation with existing abstractions for static and interactive visualizations within a single language.
• To enable authors to fluidly transition between or combine static, interactive, and animated visualization modalities.

Main Methods:

• Representing time as an encoding channel to map data fields to animation keyframes for static animations.
• Modeling time as an event stream to drive Vega-Lite selections with timer ticks, integrating animation with interaction.
• Evaluating expressiveness through a diverse gallery of examples and conducting interviews with expert developers.

Main Results:

• Animated Vega-Lite successfully integrates animation with static and interactive visualizations by treating time as an encoding channel and an event stream.
• The approach supports a wide range of animated transitions and interactions, demonstrated through a gallery of examples.
• Developer interviews revealed key tradeoffs in language design, supported transition types, and keyframe modeling.

Conclusions:

• Animated Vega-Lite offers a unified framework for creating animated visualizations that seamlessly blend with static and interactive elements.
• The proposed method simplifies the creation of complex animated visualizations by leveraging existing Vega-Lite abstractions.
• Future work should consider the identified tradeoffs to further refine the language and its capabilities for animated data visualization.