FIXED: Slowdown issue with DrawAni when drawing multiple Line charts - Official support forum

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RGraph is a JavaScript charts library based on HTML5 SVG and canvas. RGraph is mature (over 18 years old) and has a wealth of features making it an ideal choice to use for showing charts on your website.

Version 7.10 released

Version 7.10 (released in January 2026) is the latest version of RGraph and contains various updates to the code which you can see on the changelog page. There's also a big tidy up in terms of comments and a significant change to the way that the internal code is referenced which should lead to a performance improvement in effects and animations.

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New HTML datagrid

In the April 2025 (v6.21) release a new datagrid object was added. This makes it easy to add static or dynamic data tables to your pages. It can be used whether you use the canvas or SVG libraries or entirely standalone.

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Get the latest version of RGraph (version 7.10, 18th January 2026) from the download page. You can read the changelog here. There's also older versions available, minified files and links to cdnjs.com hosted libraries.

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Slowdown issue with DrawAni when drawing multiple Line charts

When drawing multiple line charts, a speed degradation issue occurs during drawAni. In RGraph.common.core.js, within the RGraph.Background.draw function:

// Reset the line dash
if (typeof args.object.context.setLineDash == 'function') {
args.object.context.setLineDash([1,0]);
}

This part takes a long time. Setting it to the default value like this:

args.object.context.setLineDash([]);

restores the speed to normal.

Please confirm.

Thank you."

Thanks very much for identifying the issue. I've added the fix into the code and it will be a part of version 6.17. The updated library is available on GitHub if you want it:

https://raw.githubusercontent.com/heyesr/rgraph/main/libraries/RGraph.common.core.js

The difference is quite pronounced!

And with the background grid code being shared between a few libraries (eg bar/line/gantt/hbar/scatter) this is unlikely to just affect the Line chart animations - but those other charts too.

Cheers.