Polyline rendering is choppy/glitchy at extreme camera angles and when clamped to ground

[carsnwd]

Sandcastle example: Sandcastle Example
Browser: Chrome

Operating System: Windows 10

Description: It appears when clamping to ground a Polyline entity that has the arrow material, that the end of the arrow is glitching/choppy. It's more noticeable with larger width arrows. Check out the sandcastle above.

[carsnwd]

I posted a similar post on the cesium-dev forums thinking maybe this is just the incorrect way of doing polylines clamped to ground with arrows? https://groups.google.com/forum/#!topic/cesium-dev/piuyNi3F8Vc

Unsure if this is a known issue, or maybe any insight why this happens 🤔

[hpinkos]

Thanks for reporting this @carsnwd ! I don't think we've noticed this issue before. I'm not sure how soon we'll be able to look into it, but we'll give you an update once we have a fix.

@likangning93 this appears to only be for ground polylines

[carsnwd]

@hpinkos Thanks!

[OmarShehata]

This seems to happen even for non clamped to ground polylines:

Although that might be a separate issue since this only happens when it's overlapping itself.

[nikitakogan]

hi there .
is there any update regarding this issue? this mode is not clamped to ground its just 2D map.

[ggetz]

@nikitakogan This may be a long shot, but you could try out #8793 as it changes the way the arrow material is rendered.

[nikitakogan]

@nikitakogan This may be a long shot, but you could try out #8793 as it changes the way the arrow material is rendered.
thanks but it didn't solve it . from what i saw its only affected 3D but not 2D.

[ggetz]

Also reported in #12427:

When you create a polyline with a big number for the width, you can see that there is many polygon.
The problem is that at certain angle ( most of the time at the same angle of the line ), those polygon are making a mess, the rotation is not enough :

Sandcastle