Fix output of Map#project during drag pan inertia

[yunluyl]

The pixel position returned from the map.project(lnglat) function drift from the real lnglat position on the map during drag pan inertia animation (the slow down effect after drag stops with speed).

[mourner]

Can you set up a JSFiddle test case to demonstrate the issue?

[yunluyl]

I set up a jsfiddle, and found out the problem is actually caused by the map.project(lnglat) function. I was using map.getCenter and map.project at the same time in my project. Somehow it made me thought the problem was caused by getCetner. I was wrong. I'll update the issue title and description.

The problem is when I use map.project to project a div to a lnglat position on the map, it drifts form the real position during drag pan inertia animation.

JSFiddle is here:
https://jsfiddle.net/3wxrt7nu/2/

[mourner]

Yeah, it looks like the same problem that causes mapboxgl.Marker elements to drift on inertia... Also reproducible when panning using keyboard.

[songyumeng]

Hi,how about this problem?Is there any way to fix?

[jfirebaugh]

This was fixed by either #6005 or #4670.