Plan and implement serialization about tapspace

[axelpale]

Each class along the inheritance line has a part to give into the serialized presentation. Thus, AbstractNode should create an object and others just add to it.

AbstractNode:

{
  id: <string>,
  children: [<item.serialize>] // preserves order
}

AbstractPlane & AbstractRectangle:

{
  _T: {s, r, tx, ty},
  _size: {width, height}
}

SpaceImage: image: {src}
SpaceHTML: html:
SpacePixel: color:

Interaction: is view specific, so should be serialized with the view

SpaceView: if serialized as a part of space, cannot be automatically mounted because we cannot store the container DOM element because it might not have an ID or anything identifying.

Method #serialize(stringify=true) so that user gets the string by default.

[axelpale]

How to serialize a SpaceView:

SpaceView#serialize(stringify: <bool>)
SpaceView#deserialize(parse: <bool>)

Deserialize must return an unmounted view.

Serialize interaction mode of each item.

{
  _interaction: {
    <item-id>: <mode>
  }
}

Consequence: targetItem must be part of the mode.

Consequence: interactions are owned by the view. This makes sense: destruction of the view must destroy the interaction artefacts. Consider view.enableInteraction(item, mode), view.disableInteraction(item), view.updateInteraction(item, mode).

[axelpale]

On the other hand, Tapspace belongs to the representation level. Why should we be able to serialize the representation? Any real-world use cases for the serialization? Let us put this to hold until we find a real-world use case.