Prettypretty is a Python package for building awesome terminal user interfaces that incorporates a powerful, and general, color library. The near seemless integration of 1970s archaic but beloved ANSI escape codes for terminal styling with 2020s color science, notably via the Oklab perceptual color space, is unique to prettypretty and makes the package truly awesome!
The first screenshot illustrates prettypretty's support for maximizing text contrast by comparing against backgrounds in all 216 colors from the 6x6x6 RGB cube of 8-bit terminal colors.
The second screenshot illustrates the reverse challenge, with prettypretty picking the background color to maximize contrast for text in all 216 colors from the 6x6x6 RGB cube. If you compare with the previous screenshot, you may notice that prettypretty's contrast metric, APCA, is not symmetric. That just why it is more accurate than, say, the WCAG 2.0 formula.
The third screenshot illustrates prettypretty's support for finding the perceptually closest color out of several colors. That's just how prettypretty performs high-quality downsampling, in this case turning the 216 colors from the 6x6x6 RGB cube into 16 extended ANSI colors.
Since almost all terminals have robust support for theming just those 16 extended ANSI colors, prettypretty doesn't just use some hardcoded set of colors but has built-in support for color themes. You can of course configure and reconfigure the current colors as you please. But prettypretty can do one better: It can automatically query a terminal for the current theme colors. The fourth screenshot illustrates the impact. When running in iTerm2 instead of macOS Terminal, prettypretty makes good use of the brighter colors in one of iTerm's builtin themes and generates a substantially different grid!
To recap, prettypretty has robust support for:
- Maximizing the label contrast for a given background color;
- Maximizing the background contrast for a given text color;
- Finding the closest color out of several;
- Using that search to perform high-quality downsampling;
- Theming the sixteen extended ANSI colors;
- Automatically determining the current terminal theme.
More is yet to come...
Copyright 2024 Robert Grimm. The code in this repository has been released as open source under the Apache 2.0.