Use ansi_colours package for better true-colour approximation

This commit is contained in:
Michal Nazarewicz
2018-09-21 15:56:09 +01:00
committed by David Peter
parent 6aa626f1c4
commit 79b960e17e
3 changed files with 14 additions and 44 deletions

View File

@ -1,32 +1,15 @@
extern crate ansi_colours;
use ansi_term::Colour::{Fixed, RGB};
use ansi_term::{self, Style};
use syntect::highlighting::{self, FontStyle};
/// Approximate a 24 bit color value by a 8 bit ANSI code
fn rgb2ansi(r: u8, g: u8, b: u8) -> u8 {
const BLACK: u8 = 16;
const WHITE: u8 = 231;
if r == g && g == b {
if r < 8 {
BLACK
} else if r > 248 {
WHITE
} else {
((r - 8) as u16 * 24 / 247) as u8 + 232
}
} else {
36 * (r / 51) + 6 * (g / 51) + (b / 51) + 16
}
}
pub fn to_ansi_color(color: highlighting::Color, true_color: bool) -> ansi_term::Colour {
if true_color {
RGB(color.r, color.g, color.b)
} else {
let ansi_code = rgb2ansi(color.r, color.g, color.b);
Fixed(ansi_code)
Fixed(ansi_colours::ansi256_from_rgb((color.r, color.g, color.b)))
}
}
@ -54,27 +37,3 @@ pub fn as_terminal_escaped(
style.paint(text).to_string()
}
#[test]
fn test_rgb2ansi_black_white() {
assert_eq!(16, rgb2ansi(0x00, 0x00, 0x00));
assert_eq!(231, rgb2ansi(0xff, 0xff, 0xff));
}
#[test]
fn test_rgb2ansi_gray() {
assert_eq!(241, rgb2ansi(0x6c, 0x6c, 0x6c));
assert_eq!(233, rgb2ansi(0x1c, 0x1c, 0x1c));
}
#[test]
fn test_rgb2ansi_color() {
assert_eq!(96, rgb2ansi(0x87, 0x5f, 0x87));
assert_eq!(141, rgb2ansi(0xaf, 0x87, 0xff));
assert_eq!(193, rgb2ansi(0xd7, 0xff, 0xaf));
}
#[test]
fn test_rgb2ansi_approx() {
assert_eq!(231, rgb2ansi(0xfe, 0xfe, 0xfe));
}