Stand-alone exhibition viewer, presenter mode and other exhibition improvements

[sammeltassen]

The Manifest Editor currently offers a minimal preview for Delft-type exhibitions. This will render the exhibition client-side after loading the manifest from the url provided as query string:

https://delft-viewer.netlify.app/#manifest={url}

We'd like to turn this prototype into a fully featured exhibition viewer, that can be used not just to preview our exhibitions but by anyone to create and share IIIF exhibitions. We have the following new features in mind:

Presenter mode
In order to display exhibitions on screens in public environments, we propose to expand the interface to include a presenter mode. This will display the exhibition as a slideshow, starting with the title block and subsequently visiting each canvas. Transitions are automatic and animated, but they can be interrupted by interacting with the canvas (for example on a touch screen in an exhibition). For a mixed-media canvas, the animation zooms to each of the describing annotations.

(Perhaps reveal.js can be used for this.)

Layout editor
The layout of exhibitions is manually encoded as behaviour properties indicating the width and height of each block. This only affects the exhibition overview page and is therefore not relevant for the presenter mode. The first Manifest Editor had a GUI to edit the layout; in order to offer this as a public tool we should either simplify the layout (presenter-mode as default?) or offer a new GUI in order to do this.

Table of contents
Exhibitions usually also have a table of contents which can be encoded as IIIF ranges. A TOC can help users to navigate the resource. An exhibition might for example be structured like a timeline, and ranges can be used to group canvasses dealing with a certain time period. There can be a sticky TOC as a horizontal bar at the top of the page, which can then be used to navigate the exhibition; a bit like is done here.

This relates to the ability to create ranges in the Manifest Editor, which doesn't yet exist?

Revision of title block
This is related to the previous two: the title block limits the layout options and should become its own separate element on top of the exhibition. This requires some new designs.

Audio and video
Since the DLCS now supports other asset types, and Canvas Panel is able to render audio and video, we'd like to be able to add video and audio annotations to canvasses as well in the Manifest Editor, which can then be played in the Exhibition Viewer.

Non-linear mixed-media canvas interaction
In order to explore the annotations on a mixed-media canvas, users now need to click through the tour. Alternatively, they might want to click a describing annotation on the canvas directly, and access the metadata from there. By clicking an annotation, they also enter the tour and can go to the previous and next one (or select another annotation).