set rgbmax {1.0 | 255} unset rgbmaxThe red/green/blue color components of an rgbimage plot are by default interpreted as integers in the range [0:255]. set rgbmax 1.0 tells the program that data values used to generate the color components of a plot with rgbimage or rgbalpha are floating point values in the range [0:1]. unset rgbmax returns to the default integer range [0:255].
Warning: This command is EXPERIMENTAL. Details may change.
In particular, future gnuplot versions may implement rgbmax as a per-file
or per-plot property rather than a global setting.