Version 5 and 6:
The windows terminal shows artifacts that appear to be extensions (failure to clip? coordinate wraparound?) of the border lines on a pm3d surface. See for example contourfill.dem.
Thanks for testing. I found the bug running a Windows emulator under linux. It is good to hear that the bug does not happen on native Windows.
Even if it is problem with the emulator rather than an actual error in gnuplot it might be possible to figure out and modify whatever internal draw commands are being incorrectly rendered.
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I cannot reproduce on gnuplot 5.4.8 and 6.0.2 on windows.
Last edit: Tatsuro MATSUOKA 2024-06-03
Thanks for testing. I found the bug running a Windows emulator under linux. It is good to hear that the bug does not happen on native Windows.
Even if it is problem with the emulator rather than an actual error in gnuplot it might be possible to figure out and modify whatever internal draw commands are being incorrectly rendered.