Lines appear to cut through the visible spectrum when changing temperature

[loganbraywork]

Test device Windows 7 laptop Operating System 6.1.7601 Browser Mozilla Firefox Problem description From https://github.com/phetsims/QA/issues/422

When adjusting the temperature slider or moving the "graph values" point, lines will sometimes appear and disappear across the visible spectrum. Of note; over time the issue does seem to come and go frequently. Steps to reproduce

1. Check the graph values box
2. Adjust Temperature slider
3. Adjust the "graph values" point Visuals

Troubleshooting information: !!!!! DO NOT EDIT !!!!! Name: ‪Blackbody Spectrum‬ URL: https://phet-dev.colorado.edu/html/blackbody-spectrum/1.0.4-rc.1/phet/blackbody-spectrum_all_phet.html?profiler Version: 1.0.4-rc.1 2019-09-03 21:34:31 UTC Features missing: touch User Agent: Mozilla/5.0 (Windows NT 6.1; Win64; x64; rv:69.0) Gecko/20100101 Firefox/69.0 Language: en-US Window: 1366x654 Pixel Ratio: 1/1 WebGL: WebGL 1.0 GLSL: WebGL GLSL ES 1.0 Vendor: Mozilla (Mozilla) Vertex: attribs: 16 varying: 30 uniform: 4096 Texture: size: 16384 imageUnits: 16 (vertex: 16, combined: 32) Max viewport: 32767x32767 OES_texture_float: true Dependencies JSON: {}

[DianaTavares]

It doesn't happen on my computer. I hope @jbphet can find the problem

[jbphet]

@loganbraywork - is this problem unique to version 1.0.4-rc.1, or is it present in the currently published version (v1.0.3)?

[KatieWoe]

I did a quick check. I did not see it to the extent shown in the video above. The video's behavior does seem concerning to me. What I saw on my device does not. @loganbraywork can you check the published version with the setup you used? I didn't see in published, but the issue wasn't as pronounced for me to begin with.

[KatieWoe]

Clarification from @loganbraywork. The pixilation in the gif is due to a low quality gif. What I saw was indicative of the issue. It does happen in the published version. Given all of this, this is a low priority issue.

[jbphet]

I'm not able to duplicate the issue on my machine in Firefox at all, neither on the main screen or my additional monitor. I just discussed it with @KatieWoe, and she was able to demonstrate it on her Windows machine, but the effect is quite subtle and went away fairly quickly after additional interaction. The GIF shown above is pretty misleading in that regard.

Since this is almost certainly a Scenery issue rather than something sim-specific, I discussed it with @jonathanolson. He said there is probably not much that could be done other than setting the renderer to canvas for the sim. This doesn't seem like a good tradeoff to me, since that would likely require another QA cycle and might introduce other tradeoffs.

Assigning to @ariel-phet to decide whether to continue to pursue this (and to see if he can duplicate, since he uses Firefox quite a bit). One option would be to kick it back to QA to get more detail on what devices this occurs and how noticeable and problematic it is in actual use. Another would be to close the issue as "won't fix".

[ariel-phet]

I tried to reproduce on my Win 7 firefox computer and saw nothing.

That would suggest this is a potentially device specific issue.

@KatieWoe if @loganbraywork was doing this testing on a personal machine, lets not use that machine for future testing.

marking as wontfix and assigning to @KatieWoe to close after reading this comment.

[KatieWoe]

It's not device specific. It does occur on multiple devices but it is very subtle. I looked at what @loganbraywork saw on his device, and it is about as subtle there. The gif posted here is badly compressed, which is why it looks so bad here. I agree it doesn't need anything else done. Closing.