Expose coveringTiles() in transform objects

[jonathanlurie]

Launch Checklist

• Confirm your changes do not include backports from Mapbox projects (unless with compliant license) - if you are not sure about this, please ask!
• Briefly describe the changes in this PR.
• Add an entry to CHANGELOG.md under the ## main section.

Description

Before the work on globe, the function .coveringTiles() used to be a method of the Transform object, it was very convenient to access the list of tiles (with z, x and y indices) that were currently displayed. This PR aims at bringing this function back to the map.transform object.

Motivations

We (at MapTiler but we are not the only ones) are creating tiled layers to display raster data. These tiles are WebGL polygons with the same footprints as regular raster tiles, just with custom shaders. When only using Mercator it was fairly easy to figure out the math to know what tile should be displayed, but with the globe view, it is much more difficult. Since the list of tiles is computed internally in Maplibre, it would be great to expose it so that third-party plugins can use it.

Contrary to a previous PR I submitted (#5158), this one does not add any function or object to the official public API.

Usage

const tileList = map.transform.coveringTiles({tileSize: 512});

The tileSize attribute is the only one mandatory (as in the internal coveringTiles() function). Since it's the default size is always 512, we could make it the default value if not provided.

[codecov]

Codecov Report

Attention: Patch coverage is 76.92308% with 3 lines in your changes missing coverage. Please review.

Project coverage is 91.82%. Comparing base (5d5a2cd) to head (2101b45).
Report is 49 commits behind head on main.

Files with missing lines	Patch %	Lines
src/geo/projection/globe_transform.ts	80.00%	1 Missing ⚠️
src/geo/projection/mercator_transform.ts	75.00%	1 Missing ⚠️
...c/geo/projection/vertical_perspective_transform.ts	75.00%	1 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #5239      +/-   ##
==========================================
- Coverage   91.83%   91.82%   -0.02%     
==========================================
  Files         281      281              
  Lines       38833    38845      +12     
  Branches     6779     6821      +42     
==========================================
+ Hits        35661    35668       +7     
- Misses       3044     3048       +4     
- Partials      128      129       +1     

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[HarelM]

This is a change in the opposite direction of what we are looking to do.
Please also read the following PR comments and problems:

• Added export to coveringTiles function #5158

I would advise to think of a better way to expose this.
The transform class is not an external API nor we are planning for it to be so.

[HarelM]

See my previous comment.

[HarelM]

Closing this for now as there was no response, if this is still relevant please let me know and I'll reopen.