x11 pm3d_resources

NB: THIS SECTION IS LARGELY IRRELEVANT IN GNUPLOT VERSION 5

By default gnuplot uses the default visual of the screen. The number of colors which can be allocated depends on the visual class chosen. On a visual class with a depth > 12bit, gnuplot starts with a maximal number of 0x200 colors. On a visual class with a depth > 8bit (but <= 12 bit) the maximal number of colors is 0x100, on <= 8bit displays the maximum number of colors is 240 (16 are left for line colors).

Gnuplot first starts to allocate the maximal number of colors as stated above. If this fails, the number of colors is reduced by the factor 2 until gnuplot gets all colors which are requested. If dividing maxcolors by 2 repeatedly results in a number which is smaller than mincolors gnuplot tries to install a private colormap. In this case the window manager is responsible for swapping colormaps when the pointer is moved in and out the x11 driver's window.

The default for mincolors is maxcolors / (num_colormaps > 1 ? 2 : 8), where num_colormaps is the number of colormaps which are currently used by gnuplot (usually 1, if only one x11 window is open).