Feature: Read geometry information from t8code

[jmark]

This PR adds geometry information retrieval from t8code into Trixi datastructures. As of now, only for Quads and Hexs.

The following idea might be implemented in the future. But there is no real use case right now. Currently, geometry information is read in during initialization phase. The plan is to change this such that the geometry information is retrieved whenever the mesh changes due to adaptation. This gives much more flexibility and has some other advantages. Thus, this PR is still a draft.

[github-actions[bot]]

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Created with :heart: by the Trixi.jl community.

[sloede]

Very cool feature, looking forward to it 😊

[benegee]

Moved the cubed sphere constructor here, making use of the new very convenient constructor which sets up tree_node_coordinates.

[codecov[bot]]

Codecov Report

Attention: Patch coverage is 96.42857% with 4 lines in your changes are missing coverage. Please review.

Project coverage is 96.09%. Comparing base (8a9fc7b) to head (3158c44).

Files	Patch %	Lines
src/meshes/t8code_mesh.jl	96.00%	4 Missing :warning:

Additional details and impacted files

```diff @@ Coverage Diff @@ ## main #1900 +/- ## ========================================== - Coverage 96.09% 96.09% -0.00% ========================================== Files 453 453 Lines 36461 36481 +20 ========================================== + Hits 35036 35055 +19 - Misses 1425 1426 +1 ``` | [Flag](https://app.codecov.io/gh/trixi-framework/Trixi.jl/pull/1900/flags?src=pr&el=flags&utm_medium=referral&utm_source=github&utm_content=comment&utm_campaign=pr+comments&utm_term=trixi-framework) | Coverage Δ | | |---|---|---| | [unittests](https://app.codecov.io/gh/trixi-framework/Trixi.jl/pull/1900/flags?src=pr&el=flag&utm_medium=referral&utm_source=github&utm_content=comment&utm_campaign=pr+comments&utm_term=trixi-framework) | `96.09% <96.43%> (-<0.01%)` | :arrow_down: | Flags with carried forward coverage won't be shown. [Click here](https://docs.codecov.io/docs/carryforward-flags?utm_medium=referral&utm_source=github&utm_content=comment&utm_campaign=pr+comments&utm_term=trixi-framework#carryforward-flags-in-the-pull-request-comment) to find out more.

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[jmark]

The PR is feature complete but needs some testing, reviewing and polishing. Furthermore, this PR depends on the latest developments in t8code, namely t8code version 2... The release is not public yet as are the Julia bindings for that. Hence, this PR has to wait for the t8code release before being ready for merging.

[jmark]

@benegee Please test your elixirs and add them to the test harness.

[benegee]

I added the tests. But I will need to adapt the error figures once the CI jobs are running.

[JoshuaLampert]

To let CI test this PR against the new t8code version from https://github.com/DLR-AMR/T8code.jl/pull/64, I think you can put the following snippet before the - name: Run tests without coverage in ci.yml:

      - name: Configure new T8code.jl version environment
        shell: julia --project="." --color=yes {0}
        run: |
          using Pkg
          Pkg.add(PackageSpec(url="https://github.com/DLR-AMR/T8code.jl", rev="bump-to-t8code-2.0.0"))
          Pkg.instantiate()

IMHO, it would be good to test the new T8code.jl version with this PR before we merge https://github.com/DLR-AMR/T8code.jl/pull/64 to be able to make potential fixes before we break something.

[sloede]

IMHO, it would be good to test the new T8code.jl version with this PR before we merge DLR-AMR/T8code.jl#64 to be able to make potential fixes before we break something.

It's good that you keep track of potential upstream incompatibilities! Alternatively, you could go ahead with the T8code.jl v2.0.0 release, then create a new Trixi.jl PR to update the compat bounds, and if errors are uncovered here, fix them with T8code.jl v2.0.1

[jmark]

The PR is feature complete but needs some testing, reviewing and polishing. Furthermore, this PR depends on the latest developments in t8code, namely t8code version 2... The release is not public yet as are the Julia bindings for that. Hence, this PR has to wait for the t8code release before being ready for merging.

Update: This PR does not actually need the latest t8code v2.0.0. Circumstances have changed. Thus, I relaxed the T8code.jl version requirement.

I suggest to introduce the latest t8code version to Trixi in a separate PR.

[jmark]

@benegee @JoshuaLampert @ranocha @sloede The PR is ready. All tests pass. Please feel free to do a review and/or refer this task someone with free capacities. Let me know if I can be of any help!

[jmark]

@sloede @ranocha Incorporated your suggestions. I kindly ask for a second round of review.

[sloede]

@ranocha would you like to take a look as well? otherwise, this can be merged

[jmark]

@sloede @ranocha The PR should be ready for merge. Thank you very much for your reviews!