Color picker: Broken pixel along vertical axis

[michelkaporin]

Version: Insiders b73b7df

See the screenshot above. Interestingly, not all color values produce this result (e.g. #68c3a3 paints fine).

[joaomoreno]

He's alive!!! Do you like the new horizontal picker bars? 🥇

Funny broken pixel, though. Does it always reproduce on your machine? No steps, just open it?

[michelkaporin]

Haha, I am here! Yeah, they're awesome, like them 👍 Didn't have a time for a final touch on them before leaving, was focused on finishing off the core implementation 😄

It always reproduces, no steps, just pick the #333333 color.

Also I've looked at your code refactorings around the picker, you made it really sleek 👍 nice work! 🔢

[joaomoreno]

Strange:

[michelkaporin]

@joaomoreno really strange, and the code remained the same as I've seen.

If I tweak window.zoomLevel to values different to default, it starts to appear fine.

OS: Windows
Resolution: 1920x1080
Scaling: 100%

[rebornix]

It took me a while to find the way to reproduce (before that I even wanted to ask you to check whether your screen is broken for a second ...).

• No reproduce on macOS
• Reproduce on Windows 10, Scaling 100% and Zoom Level 0. If we change the Scaling or Zoom Level, the green line is gone.
• Chrome Dev Tools doesn't have this problem.

[rebornix]

After exposing the API to monaco, I can reproduce this issue in Chrome on macOS always with no scale. Once I scale the webpage, the green line is one.

This is probably a blocker for releasing to Monaco Editor @joaomoreno . @alexandrudima any idea of how this magic green dots happen in canvas?

[rebornix]

It only happens in Chrome (macOS 100% Zoom and Windows 10 Hdpi 100% Scale), didn't see any issue in Safari and Edge. Tried several ways to troubleshoot but didn't see what we did wrong. A workaround here is adding a middle stop point to the linear gradient, which makes Chromium canvas rendering correct.

[joaomoreno]

Their constant position might give us a clue on why they happen... although I got none. 😕

[rebornix]

The workaround seems good, so visually this issue is gone. I'd like to put it into backlog and one day I can know the root cause of this canvas problem.