Fixes roundPixels calculation differences between v4 and v5

[themoonrat]

Description of change

Fixes issue descripted in #6232 with roundPixels implementation difference between v4 and v5 for resolutions less than 1.

Pre-Merge Checklist

• Lint process passed (npm run lint)
• Tests passed (npm run test)

[themoonrat]

Added a PR using the PIXI.settings.RESOLUTION settings.....
But that's not ideal if a different resolution is passed directly into the renderer.

So help on a rethink of this is required please! :)

[ivanpopelyshev]

Can you add this to settings.RESOLUTION description?

Btw, we have separate RESOLUTION and FILTER_RESOLUTION

[ivanpopelyshev]

I'm happy that you solved it for me. I didnt know what to do with that thing back then when I moved it to calculateVertices()

[bigtimebuddy]

@themoonrat could you possibly add a unit-test or two for this? It's a very subtle thing, but has some implications visually. Would be helpful to make sure we handle that case correctly in the future.

[codecov-io]

Codecov Report

Merging #6234 into dev will decrease coverage by 0.01%.
The diff coverage is 0%.

@@            Coverage Diff             @@
##              dev    #6234      +/-   ##
==========================================
- Coverage   77.14%   77.13%   -0.02%     
==========================================
  Files         203      203              
  Lines       10314    10316       +2     
==========================================
  Hits         7957     7957              
- Misses       2357     2359       +2

Impacted Files	Coverage Δ
packages/mesh/src/Mesh.js	61.48% <0%> (-0.42%)	⬇️
packages/sprite/src/Sprite.js	92.15% <0%> (-0.46%)	⬇️

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[themoonrat]

@bigtimebuddy Sure, I'll have time on Friday to see if this can be unit tested in a meaningful way. Hopefully I can look in the vertex data to explain why putting 2 store sprites side by side does not work without this PR

[bigtimebuddy]

Thanks @themoonrat if you could add a unit-test PR later, that'd be great.