#2285 png notruecolor ignores maxcolor with defined palette

[Antonio Ospite]

Hi,

while playing with defined palettes and maxcolors as shown on http://www.gnuplotting.org/tag/maxcolors/ I found out that the png terminal does not seem to honour the maxcolors settings in notruecolor mode.

See the attached script which shows the difference between different terminals and options.

The issue can be worked around with just specifying "truecolor", or using proper interval boudaries in the palette and avoid maxcolors altgether, but it was still surprising as a user so I thought I'd report it.

Tested on linux also with a self compiled gnuplot from git 5.4.rc2-8-ga2beaa0a0.

Thanks,
Antonio

[Antonio Ospite]

Thanks @sfeam the change from commit 19ebc5024be2b0bd661ab63a0355502357b9caf1 works fine.

However with the master branch I see that the SVG file produced by my tests script has a red-ish color for the plot borders, can you see this? Should I report the issue separately?

Thanks, Antonio

[Ethan Merritt]

I touched only the libgd code. Anything to do with svg is something else entirely.

[Antonio Ospite]

Yes, I figured that, I was just asking if you saw somehting strange with the same test script, but it turned out to be a local problem... I had some experimental changes to the svg terminal I forgot about.

Thanks again.

Ciao, Antonio