Resync with WGPU 0.20.

[John-Nagle]

Checklist

• CI Checked:
  • cargo fmt has been ran
  • cargo clippy reports no issues
  • cargo test succeeds
  • cargo rend3-doc has no warnings
  • cargo deny check issues have been fixed or added to deny.toml
• Manually Checked:
  • [x ] relevant examples/test cases run
  • [x ] changes added to changelog
    • Add credit to yourself for each change: Added new functionality @githubname.

Related Issues

Description

Bring Rend3 up to date with current wgpu (0.20), egui, and winit.

Fix outstanding warning messages.

Advance version to 0.20.0 to match wgpu. Intent is to follow wgpu version from now on when possible. After testing, this version should be pushed to "crates.io" as version 0.20.0.

[John-Nagle]

Fixing minor problems.

The default scene render test does not match the exemplar image when I run "cargo test" locally, with the reference images loaded. This appeared after I converted everything to use the current "image" crate. The "Bistro" scene does pass.

Exemplar

As rendered.

Diff.

That diff is not totally black. Bring it into an image editor and expand the black out to a wider range of intensities.

    Image Comparison Results
    Expected Mean (0.028385) to be under expected maximum (0.01): FAIL

    Mean: 0.028384654
     Min: 0
     25%: 0.029385423
     50%: 0.039566796
     75%: 0.049417663
     95%: 0.065355726
     99%: 0.076764226
     Max: 0.28033736
    Failed!

[John-Nagle]

Diff, black range expanded:

There are differences, but they're down near the noise threshold. Real bug, or routine difference?

[John-Nagle]

Can I trigger the CI cycle myself, or does someone else have to do that?