Polyline artifacts depending on camera position

[shunter]

In master I'm seeing new artifacts when rendering polylines. Possibly this is related to the polylines on terrain addition?

Sandcastle

note: sandcastle is the hosted version which does not have the problem. copy/paste the code locally

[hpinkos]

@shunter I'm seeing the same thing in master and in 1.46. This is a screenshot from cesiumjs.org

I hardly see that flicker happen at all though. Does it happen frequently for you? Try setting scene.logarithmicDepthBuffer = false to see if that fixes it

[shunter]

I tried harder on the version on cesiumjs.org and I was able to get it there:

However, it's way more prevalent in master.

[hpinkos]

Hmm okay. It's about the same in 1.46 and master for me. But it does seem to be logdepth related. I can't reproduce it at all in 1.44 but can in 1.45

cc @bagnell

[hpinkos]

Marking this next release because it's regression. If we can't figure it out in time for 1.47 we definitely should for 1.48

[shunter]

Adding viewer.scene.logarithmicDepthBuffer = false;

to turn off logarithmicDepthBuffer makes it much much worse:

[shunter]

Fixed by #6751. Back to being the same quality as last release - that is, rare artifacts that I speculate are frustum boundaries.

[likangning93]

@shunter are you sure? That PR wasn't supposed to address standard polylines.

[shunter]

I went back through versions of master and can't seem to reproduce with my original code with any previous version I try. Not sure what's going on, maybe there was some sort of file mismatch.

Current master does have the artifacts from the gifs above if you turn log depth off. Not sure if turning log depth off is expected to work anymore, I haven't followed related changes. If you think that's a problem we should re-open.

[slizer2000]

@shunter Im not sure if it will be fixed by #6751.

I get the same issue when the followSurface property is set to false but not when set to true...

Only started happening after v1.44.0 .

followSurface=false

followSurface=true

Sandcastle

Edit: updated sandcastle link to proper

[hpinkos]

@slizer2000 does this happen in Cesium 1.47? Also, you linked to a pull request instead of a Sandcastle example by mistake. Can you please share your Sandcastle example? Thanks!

[slizer2000]

@hpinkos apologies. I have updated the link. Yes it happens in 1.4.7. I have had to revert back to 1.44 in my project to avoid this issue. I becomes more apparent as you zoom into the geo

[slizer2000]

there is another bug that when in 2D mode, the polyline gets cut in half or disapears all together

[hpinkos]

Thanks @slizer2000, I was able to reproduce the flickering you're seeing. For now, you can set viewer.scene.logarithmicDepthBuffer = false; as a workaround.

@bagnell could you look into this?

[lilleyse]

If it helps here is another demo showing the problem: Sandcastle

[lilleyse]

Another polyline artifact but only when log depth is off. I wasn't able to git bisect due to unrelated shader errors but it seems to have been introduced with the log depth changes.

Sandcastle link

UPDATE: fixed #7209

[mramato]

Just a reminder that the release is this Wednesday. We should really try and get all showstopper issues addressed by the end of today.

[tfili]

Is anyone looking at addressing this for tomorrow?

[bagnell]

I'm looking at it.

[themikelester]

What was the result of this?

[hpinkos]

Hi @themikelester, we fixed some of the polyline issues but are still looking into one or two others

[hpinkos]

Also: https://groups.google.com/forum/#!topic/cesium-dev/NZwZnQnmC2U

[ggetz]

(@bagnell?)

This issue is marked for next release, so we should try to get in a fix for next week. Thanks!

[bagnell]

I wasn't able to find the cause for the last release. I'm still looking into it.

[mramato]

Since there are multiple issue sin this bug, I wrote up two new issues to keep things separate. We'll close this issue with #6955 is merged, since that fixes the original reported issue by @shunter

[lilleyse]

I mentioned this in #7209 as well - I'm still seeing some flickering in https://github.com/AnalyticalGraphicsInc/cesium/issues/6741#issue-336373649 even with the changes in #7209. I think it may be due to driver differences. I only noticed flickering with AMD and not Nvidia, and both work in older versions of Cesium (I tested 1.34).

[cesium-concierge]

Congratulations on closing the issue! I found these Cesium forum links in the comments above:

https://groups.google.com/forum/#!topic/cesium-dev/NZwZnQnmC2U

If this issue affects any of these threads, please post a comment like the following:

The issue at https://github.com/AnalyticalGraphicsInc/cesium/issues/6741 has just been closed and may resolve your issue. Look for the change in the next stable release of Cesium or get it now in the master branch on GitHub https://github.com/AnalyticalGraphicsInc/cesium.

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[lilleyse]

Opened https://github.com/AnalyticalGraphicsInc/cesium/issues/7360 to address https://github.com/AnalyticalGraphicsInc/cesium/issues/6741#issuecomment-434846690.

[lilleyse]

Moved the forum issue https://groups.google.com/forum/#!topic/cesium-dev/NZwZnQnmC2U over to https://github.com/AnalyticalGraphicsInc/cesium/issues/7072.

[lilleyse]

Opened https://github.com/AnalyticalGraphicsInc/cesium/issues/7374 because we had to revert https://github.com/AnalyticalGraphicsInc/cesium/pull/6955 in https://github.com/AnalyticalGraphicsInc/cesium/pull/7373.