Specifies the style of the key, or legend, that shows what each colour-range means. If a scalename is not given, then "DEFAULT" is assumed. Valid stylenames are: 'classic', 'horizontal', 'vertical', 'inverted' and 'tags'.
Classic has a line for each SCALE range defined. 'vertical' and 'horizontal' are fixed-size, showing a continuous block from 0-100% usage, which is much more useful when gradient SCALEs are used, or when you have a large number of SCALE lines in one scale. 'inverted' is the same as 'vertical', but with the zero point at the bottom, thermometer-style. Finally, 'tags' is the same style as 'classic', but instead of percentages, it shows the tag string from the end of the SCALE lines, if there are any.
For 'horizontal' and 'vertical' styles, you can optionally add an additional parameter, which specifies the longer dimension of the legend in pixels. That is, for a horizontal legend, it specifies the width. The other dimension is calculated from the size of the font used (see KEYFONT).
Classic Style
Horizontal Style
Vertical Style
Inverted Style
Tags Style
You can hide the percentage signs in the key, by setting key_hidepercent_scalename to 1
If you have a 0->0 line in your SCALE, then you can hide that in the key, by setting key_hidezero_scalename to 1