Tileset3D support modelMatrix

[radoslavirha]

Hi,

would it be possible to implement modelMatrix in Tileset3D?

Described here: visgl/deck.gl#7309 (comment)

Thanks

[ibgreen]

(Updated PR title.)

Yes, it should of course be possible, and we'd certainly consider a PR, however:

• This affects the traversal part of Tileset3D (traversing the hierarchy and selecting tiles in view based on current viewport(s)).
• Unfortunately, traversal is the most fragile and hacky part of the current implementation (e.g. a number of glitches become evident when using the new Google 3D tiles)
• this code is due for a major refactor. (Perhaps basing it the latest traversal implementation in Cesium.)

So

• fixing modelMatrix in the current implementation does not seem very motivating. It is likely a bit fiddly and would need to be redone after the refactor.
• fixing it during the refactor makes sense, but so far, no one has signed up for working on the refactored traversal.

Also, adding modelMatrix support to traversal primarily handles the case when then model matrix shifts the view enough that different tiles need to be loaded. It seems to me that modelMatrix still needs to be support by Tile3DLayer.