GL plots seem to be using up multiple GL contexts with Plotly 1.37.1

[brian428]

Previously, we were able to show 7-8 or more WebGL plots at once. With 1.37.1, we're hitting the browser GL context limit (typically 16) much earlier. When showing 7 plots, the first two immediately lose their GL contexts and appear as blank.

Here is a repro case: http://jsfiddle.net/brian428/fqhb7kk9/

It seems like Plotly is using up multiple GL contexts for each scattergl plot. With 7 plots, there are 5 console warnings about losing contexts, so it appears that each scattergl plot is using 3 GL contexts for some reason.

We need to show multiple plots together (and allow each one to be individually manipulated by the user), so this is a blocking issue. Can someone take a look?

[etpinard]

Duplicate of #2333

[brian428]

Thanks, I missed that one. Would it help you if add my repro case to that ticket?

[brian428]

Also just to be clear, we had been on 1.35 I believe. So it seems like maybe something changed between 1.35 and 1.37 that made this worse. Maybe the addition of Splom?

[etpinard]

@brian428 sorry for the wait. We just merged #2662 which makes scattergl graphs use 2 (not 3) WebGL contexts as was the case before 1.36.0.

A little more info on the topic: we use two WebGL contexts per scattergl (and splom) graph to improve selection (via select-box and lasso) performance. Since 1.33.0 , WebGL contexts are shared across subplots on the same graph <div>. So, one way to decrease the number of created contexts would be to merge your graphs into subplots on the same graph <div> when possible.

Now, ticket #2333 has some thoughts on sharing WebGL contexts across graph <div>s. Hopefully using an external library like multi-regl will be enough. If not, we might have to add another API method e.g. Plotly.dashboard to solve this problem.

I'll close this issue. But please feel free to comment on #2333.