Allow undoing interactions

[sehilyi]

We need to provide undo/redo functionality for every interactions. For this, we can add undo/redo buttons for this (Just like a "undo" button on the top in Voyager2: https://idl.cs.washington.edu/papers/voyager2/).

To implement this, one option would be storing previous N viewConfig and Options files, and bring the previous one upon undo button.

[keller-mark]

The viewConfig initialXDomain, initialYDomain, projectionXDomain, projectionYDomain fields are updated on every zoom / pan interaction so we would probably want to ignore those fields and diff the view config to determine which ones are actually "different" enough to need to store

[sehilyi]

Sounds good. We will need to ignore small changes in the undoing interactions.

In zoom/pan interaction, we may want to additionally consider the time duration for each zoom/pan setting as users are more likely to take more time for the settings of their interest?

Relevant high-level question:

• What interactions should we consider as significant interaction steps that are worth-showing upon undoing interaction?

[sehilyi]

Interactions worth recording:

• zooming (HiGlass by viewConfig)
• panning (HiGlass by viewConfig)
• gene search (HiGlass*)
• genomic interval selection (cisvis by options)
• API search (cisvis by options)
• sort rows (cisvis by options)
• aggregate rows (cisvis by options)
• filter rows (cisvis by options)
• add tracks (cisvis by options)
• highlight rows? (cisvis by options)
• seeing tooltip? (HiGlass* & cisvis by options)

[*] Things we need to update HiGlass if we want to support recording those interactions