General Usage
Many commands in gappa produce output visualizations that use colors. Depending on the context, these can either be single colors, or a list or gradient of colors.
Single colors can be specified
- by name, as one of the 140 web colors, that is, the basic 16 html color names and the extended 124 X11 color names. This is case-independent and insensitive to white spaces.
- by name, as one of the 954 xckd colors, again case- and white-space-insensitive.
- by hex code in the format
#RRGGBBor#RRGGBBAA(with alpha, which might be useful when producing svg fules), using hexadecimal coding for each of the red, green, and blue values, case insensitive. For example, use#000000for black and#fffffffor white. Note that#also happens to denote the start of a comment in command lines; hence, you probably need to put this in quotation marks.
A typical color specification might hence look like this: --under-color "#ff00ff" or --mask-color orange.
Gradients and lists of colors can be specified as
- a comma-separated list of colors following the above specifications for single colors, or
- as one of the following named color lists/gradients:
Depending on context, not all of these lists might be available; it does for example not make much sense to use a categorical qualitative color list as a gradient.
When specifying individual colors to build a custom gradient, these colors are evenly spaced out across the range of values, and then linearly interpolated to create the gradient.