[masswerk]

Here's a somewhat older approach splitting charts into linear runs of 1x1 images, which has some statistics at the bottom of each chart:

https://www.masswerk.at/demospace/relayWeb_en/chartset.htm

(Or see https://www.masswerk.at/demospace/relayWeb_en/welcome.htm and select "charts". Total time for calculations and rendering was then in the about 1 sec range. The real problem for using this in production was that these charts could be printed on Windows with Postscript printers only. I think, this was eventually fixed in Windows 98 SE.)