More On Colors

There's a little more to the color commands that was not described earlier. For example, there is a color .black that can be used. Since the background is black, this command is sort of like making it invisible, but such items can be selected (although you won't be able to tell except for any side effects you may cause on moving a selected, invisible point).

In addition to all the non-colors like .smear, .blink, .blink1, .blink2 and .invisible (or .in, for short), Geometer deals with 32 colors whose names are .c0, .c1, ..., .c31. The first 8 of these have aliases: .c0 = .black, .c1 = .red, .c2 = .green, .c3 = .yellow, .c4 = .blue, .c5 = .magenta, .c6 = .cyan, and .c7 = .white.

The colors from .c8 through .c15 are non-black, and .c16 on are simply white. However, you can redefine any of these colors (including the first 8, although you'd probably be nuts to do so) as in the following example:

.c10 = (.4, .5, .8);

The three floating-point values must lie between 0.0 and 1.0 and they represent the amount of red, green, and blue in the color to be displayed. The example above will define color .c10 to use 40% of full red, 50% of full green, and 80% of full blue.

You can use the alternate color names exactly as you do the standard names like .red, .blue, et cetera.