Add LookAt function to GizmoVisual class

[iche033]

🎉 New feature

Summary

The LookAt function updates the rotation visuals in a GizmoVisual so that they always face the specified position. This is used by TransformController so that the rotation visuals (handles) are always positioned in front of the attached object w.r.t the camera so that they are easy to click on by the mouse.

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.

[ahcorde]

LGTM, just a minor comment

[codecov]

Codecov Report

Merging #882 (14a457c) into main (71bde82) will increase coverage by 0.14%.
The diff coverage is 95.45%.

❗ Current head 14a457c differs from pull request most recent head f137e5b. Consider uploading reports for the commit f137e5b to get more accurate results

@@            Coverage Diff             @@
##             main     #882      +/-   ##
==========================================
+ Coverage   75.12%   75.26%   +0.14%     
==========================================
  Files         176      176              
  Lines       16858    16853       -5     
==========================================
+ Hits        12664    12685      +21     
+ Misses       4194     4168      -26     

Files	Coverage Δ
include/gz/rendering/base/BaseGizmoVisual.hh	88.15% <100.00%> (+0.62%)	⬆️
src/TransformController.cc	63.45% <0.00%> (+5.04%)	⬆️

[azeey]

Can we merge this after Harmonic?

[iche033]

Can we merge this after Harmonic?

yes, no hurry