I’d like to suggest to generate SVG files instead of PNG. If a PDF or HTML report is generated and multiple images are positioned alongside each other, SVG would allow to zoom in while PNG would be barely readable.
Since there are several libraries available which add interactivity to SVG charts, it would also be a great future feature providing interactive HTML-Reports.
PS: The JFreeChart already have the option but since visualization node technology was changed to ECharts, continuing to consolidate the existing feature would certainly:
help adoption rates which in turn
reduces code maintenance efforts
eases support by the community
reduces required effort to start kniming
5 would just be awesome
we already have an internal ticket to add SVG support to the new views (internal reference UIEXT-714). ECharts offers the possibility to switch between a canvas (png) renderer and a SVG renderer. Currently we use the canvas renderer as this is more performant in general, but we know that for reporting SVG’s might be the better option. I will add a +1 to the ticket for you.
Thanks Daniel. Just in case UIEXT-714 will get worked on, your colleagues might want to kill two birds with one stone as both, the Report PDF and HTML Writer, do not support SVG and dur to the lack of support of negative values in the chart nodes, creating reports is negatively, pun intended, impacted.