Add possibility to save charts as images programmatically

[kMutagene]

Creating images locally without having to open plots and click on the save as image button would be awesome. This however will take some work.

The only way i found to do this so far is using Orca, which is a command line utility that plotly itself uses to render images. Orca can be either installes as npm module, conda package, or deployed as a docker container. All of these add some overhead but i still think this is usefull. I will start to implement some functions to call orca functions and we will see how it goes.

[sanchez]

It is overkill but it would be possible to use Puppeteer-Sharp to render the page and then either inject JavaScript and take the screenshot or use Puppeteer to take the screenshot on page render finish

[kMutagene]

On the first look, this actually seems to be less overhead than using Orca in a docker container, thanks for the tip!

[kMutagene]

thanks again @sanchez , i had a short go at it and it instantly worked. Here is a POC gist for future reference:

https://gist.github.com/kMutagene/afadbd5b9cb8e6b0401e94338a2644e4

the rendered chart:

[sanchez]

no worries, excited to see this feature incorporated!

idk if plotly will allow you to but you might want to wait for a response from plotly to confirm that the chart has been rendered and the page is done. A dirty way would just be a fixed delay as well

[kMutagene]

The way to go here is providing a Kaleido interface to render Plotly.NET Charts as images.

[nhirschey]

I'd like to register my interest in this feature so that I can easily include F#-generated figures in latex documents.

[ilyalatt]

I've published a package that uses PuppeteerSharp and Chromium to render charts.
It's called Plotly.NET.PuppeteerRenderer.
The code is written in C# but it should not be a problem to use it in F#.
Here's a snippet:

var chart = Chart.Line<int, int, int, int>(
    x: new[] { 1, 2, 3 },
    y: new[] { 4, 5, 6 }
);

await using var renderer = await PlotlyRenderer.FetchBrowserAndLaunch();
var png = await renderer.Render(1024, 768, chart.ToFullScreenHtml());
await File.WriteAllBytesAsync("chart.png", png);

[kMutagene]

@ilyalatt thanks for that!

[kMutagene]

closed via #94. The docs for the new Plotly.NET.ImageExport package can be found here