Thanks for the hint, Rik. I also try to slowly move over to fltk. But my current installation still has gnuplot as default, since the fltk plots still have some esthetic drawbacks (linewidth, fontsize), which I heard will be fixed.

So currently I'll report gnuplot errors in octave along the way, when I hit them. But I won't get upset if noone makes it his priority to fix them.

Here is how to reproduce the behavior:

graphics_toolkit('gnuplot');
demo pie3

Instead of some nice 3d pie charts I only get an error message:

1>> demo pie3
pie3 example 1:
 clf;
 pie3 ([5:-1:1], [0, 0, 1, 0, 0]);
 colormap ([1,0,0;0,1,0;0,0,1;1,1,0;1,0,1;0,1,1]);
 title ('pie3() with exploded wedge');

error: __go_draw_axes__: gnuplot (as of v4.2) only supports 3-D filled triangular patches
error: called from:
error:   /opt/octave-3.8.1/scripts/plot/util/private/__go_draw_axes__.m at line 655, column 18
error:   /opt/octave-3.8.1/scripts/plot/util/private/__go_draw_figure__.m at line 172, column 17
error:   /opt/octave-3.8.1/scripts/plot/util/__gnuplot_drawnow__.m at line 86, column 5
error: input: reading user-input failed!
error:   /opt/octave-3.8.1/scripts/testfun/demo.m at line 124, column 7

This only happens with gnuplot. Fltk plots seem to be fine.

This happened with the octave release 3.8.1 as well as the current pre-release 3.8.2-rc1 under Ubuntu Linux. I don't know if it happens under Windows as well.

I use Gnuplot 4.6.1-1 (package 4.6.1-1~precise1 from the standard repository of Ubuntu 12.04).