Expose Vertex & Index raw ptrs for efficient reading

[darksylinc]

🎉 New feature

Summary

This PR exposes vertex & index raw ptrs.

It is necessary to significantly improve performance of Ogre2RayQuery.

It is up to caller to ensure this unsafe pointers are read properly and hence its usage is discouraged; only when necessary.

Checklist

• Signed all commits for DCO
• Added tests
• Added example and/or tutorial
• Updated documentation (as needed)
• Updated migration guide (as needed)
• Consider updating Python bindings (if the library has them)
• codecheck passed (See contributing)
• All tests passed (See test coverage)
• While waiting for a review on your PR, please help review another open pull request to support the maintainers

Note to maintainers: Remember to use Squash-Merge and edit the commit message to match the pull request summary while retaining Signed-off-by messages.

[codecov]

Codecov Report

Merging #474 (732dc1f) into gz-common5 (431a2ad) will increase coverage by 0.00%.
The diff coverage is 100.00%.

@@             Coverage Diff             @@
##           gz-common5     #474   +/-   ##
===========================================
  Coverage       80.60%   80.61%           
===========================================
  Files              90       90           
  Lines           10237    10241    +4     
===========================================
+ Hits             8252     8256    +4     
  Misses           1985     1985           

Impacted Files	Coverage Δ
graphics/src/SubMesh.cc	91.19% <100.00%> (+0.11%)	⬆️

Help us with your feedback. Take ten seconds to tell us how you rate us. Have a feature suggestion? Share it here.

[scpeters]

I think this could target gz-common5 since this doesn't break API/ABI and that is what gz-rendering8 is still using

[mjcarroll]

@darksylinc I think at this point, if you want to retarget to gz-common5 as @scpeters suggested, we should be good to go here.

[iche033]

changes look good. Maybe add tests for the new APIs in SubMesh_TEST.cc

[darksylinc]

• Rebased and retargeted the PR to gz-common5
• Added requested unit tests

[darksylinc]

The submesh test if failing on macOS. Anyone has any idea why?

UPDATE: Nevermind, the info DOES appear.
The detailed info doesn't appear.

[darksylinc]

Test fixed. All tests sre green.