Plotly.downloadImage seems to not always respect layout setting

As mentioned here https://github.com/plotly/plotly.js/issues/2098#issuecomment-337622647 Plotly.downloadImage should accept a layout object and it does normally. When you define your layouts like I did in the following fiddle, it never respects a given layout object but rather chooses the layout object used for drawing the plot. (You can switch plotLayout and downLayout in the given fiddle around to test this.)

https://jsfiddle.net/7co1nf0v/

So how can I achieve keeping this namespace but also being able to pass a different layout for the downloadImage than for the plot drawing? Please point me towards any mistakes I may have made, I’m not totally firm with JavaScript yet. 😹

[alexcjohnson]

(BTW, this kind of question is a better fit for community.plot.ly - github issues should be for bug reports or feature requests)

That’s the intended behavior. We could certainly do a better job of describing this in the docs… but you can’t put data or layout into the second argument, they need to be in the first argument (either directly, as you have it in your second fiddle, or already attached to a div).

Plotly.downloadImage is a wrapper around Plotly.toImage, which is described more in the source

If anyone can point me towards how I could reuse the given graph and just “overload” it with another layout, so I don’t need to redraw everything in the background

No matter what you do, we’re going to redraw the plot in the background when you ask for an image of it, since the image options can change how it is drawn. But the way you do it in your second fiddle is the correct way to do it, there are no unnecessary redraws there.

[antoinerg]

Hello @Braintelligence and thank you for reporting this!

From my understanding, Plotly.downloadImage will only honor a layout object if it is provided in the first argument. In your first fiddle, the layout object is provided in the second argument which is why it doesn’t work. Your second fiddle does work because the layout is provided in the first argument!