Files
xterm.js/src/browser/ColorManager.ts
T
2019-11-25 11:58:26 -08:00

219 lines
7.8 KiB
TypeScript

/**
* Copyright (c) 2017 The xterm.js authors. All rights reserved.
* @license MIT
*/
import { IColorManager, IColor, IColorSet, IColorContrastCache } from 'browser/Types';
import { ITheme } from 'common/services/Services';
import { fromCss, toCss, blend, toRgba, toPaddedHex } from 'browser/Color';
import { ColorContrastCache } from 'browser/ColorContrastCache';
const DEFAULT_FOREGROUND = fromCss('#ffffff');
const DEFAULT_BACKGROUND = fromCss('#000000');
const DEFAULT_CURSOR = fromCss('#ffffff');
const DEFAULT_CURSOR_ACCENT = fromCss('#000000');
const DEFAULT_SELECTION = {
css: 'rgba(255, 255, 255, 0.3)',
rgba: 0xFFFFFF4D
};
// An IIFE to generate DEFAULT_ANSI_COLORS. Do not mutate DEFAULT_ANSI_COLORS, instead make a copy
// and mutate that.
export const DEFAULT_ANSI_COLORS = (() => {
const colors = [
// dark:
fromCss('#2e3436'),
fromCss('#cc0000'),
fromCss('#4e9a06'),
fromCss('#c4a000'),
fromCss('#3465a4'),
fromCss('#75507b'),
fromCss('#06989a'),
fromCss('#d3d7cf'),
// bright:
fromCss('#555753'),
fromCss('#ef2929'),
fromCss('#8ae234'),
fromCss('#fce94f'),
fromCss('#729fcf'),
fromCss('#ad7fa8'),
fromCss('#34e2e2'),
fromCss('#eeeeec')
];
// Fill in the remaining 240 ANSI colors.
// Generate colors (16-231)
const v = [0x00, 0x5f, 0x87, 0xaf, 0xd7, 0xff];
for (let i = 0; i < 216; i++) {
const r = v[(i / 36) % 6 | 0];
const g = v[(i / 6) % 6 | 0];
const b = v[i % 6];
colors.push({
css: toCss(r, g, b),
rgba: toRgba(r, g, b)
});
}
// Generate greys (232-255)
for (let i = 0; i < 24; i++) {
const c = 8 + i * 10;
colors.push({
css: toCss(c, c, c),
rgba: toRgba(c, c, c)
});
}
return colors;
})();
/**
* Manages the source of truth for a terminal's colors.
*/
export class ColorManager implements IColorManager {
public colors: IColorSet;
private _ctx: CanvasRenderingContext2D;
private _litmusColor: CanvasGradient;
private _contrastCache: IColorContrastCache;
constructor(document: Document, public allowTransparency: boolean) {
const canvas = document.createElement('canvas');
canvas.width = 1;
canvas.height = 1;
const ctx = canvas.getContext('2d');
if (!ctx) {
throw new Error('Could not get rendering context');
}
this._ctx = ctx;
this._ctx.globalCompositeOperation = 'copy';
this._litmusColor = this._ctx.createLinearGradient(0, 0, 1, 1);
this._contrastCache = new ColorContrastCache();
this.colors = {
foreground: DEFAULT_FOREGROUND,
background: DEFAULT_BACKGROUND,
cursor: DEFAULT_CURSOR,
cursorAccent: DEFAULT_CURSOR_ACCENT,
selection: DEFAULT_SELECTION,
selectionOpaque: blend(DEFAULT_BACKGROUND, DEFAULT_SELECTION),
ansi: DEFAULT_ANSI_COLORS.slice(),
contrastCache: this._contrastCache
};
}
public onOptionsChange(key: string): void {
if (key === 'minimumContrastRatio') {
this._contrastCache.clear();
}
}
/**
* Sets the terminal's theme.
* @param theme The theme to use. If a partial theme is provided then default
* colors will be used where colors are not defined.
*/
public setTheme(theme: ITheme = {}): void {
this.colors.foreground = this._parseColor(theme.foreground, DEFAULT_FOREGROUND);
this.colors.background = this._parseColor(theme.background, DEFAULT_BACKGROUND);
this.colors.cursor = this._parseColor(theme.cursor, DEFAULT_CURSOR, true);
this.colors.cursorAccent = this._parseColor(theme.cursorAccent, DEFAULT_CURSOR_ACCENT, true);
this.colors.selection = this._parseColor(theme.selection, DEFAULT_SELECTION, true);
this.colors.selectionOpaque = blend(this.colors.background, this.colors.selection);
this.colors.ansi[0] = this._parseColor(theme.black, DEFAULT_ANSI_COLORS[0]);
this.colors.ansi[1] = this._parseColor(theme.red, DEFAULT_ANSI_COLORS[1]);
this.colors.ansi[2] = this._parseColor(theme.green, DEFAULT_ANSI_COLORS[2]);
this.colors.ansi[3] = this._parseColor(theme.yellow, DEFAULT_ANSI_COLORS[3]);
this.colors.ansi[4] = this._parseColor(theme.blue, DEFAULT_ANSI_COLORS[4]);
this.colors.ansi[5] = this._parseColor(theme.magenta, DEFAULT_ANSI_COLORS[5]);
this.colors.ansi[6] = this._parseColor(theme.cyan, DEFAULT_ANSI_COLORS[6]);
this.colors.ansi[7] = this._parseColor(theme.white, DEFAULT_ANSI_COLORS[7]);
this.colors.ansi[8] = this._parseColor(theme.brightBlack, DEFAULT_ANSI_COLORS[8]);
this.colors.ansi[9] = this._parseColor(theme.brightRed, DEFAULT_ANSI_COLORS[9]);
this.colors.ansi[10] = this._parseColor(theme.brightGreen, DEFAULT_ANSI_COLORS[10]);
this.colors.ansi[11] = this._parseColor(theme.brightYellow, DEFAULT_ANSI_COLORS[11]);
this.colors.ansi[12] = this._parseColor(theme.brightBlue, DEFAULT_ANSI_COLORS[12]);
this.colors.ansi[13] = this._parseColor(theme.brightMagenta, DEFAULT_ANSI_COLORS[13]);
this.colors.ansi[14] = this._parseColor(theme.brightCyan, DEFAULT_ANSI_COLORS[14]);
this.colors.ansi[15] = this._parseColor(theme.brightWhite, DEFAULT_ANSI_COLORS[15]);
// Clear our the cache
this._contrastCache.clear();
}
private _parseColor(
css: string | undefined,
fallback: IColor,
allowTransparency: boolean = this.allowTransparency
): IColor {
if (css === undefined) {
return fallback;
}
// If parsing the value results in failure, then it must be ignored, and the attribute must
// retain its previous value.
// -- https://html.spec.whatwg.org/multipage/canvas.html#fill-and-stroke-styles
this._ctx.fillStyle = this._litmusColor;
this._ctx.fillStyle = css;
if (typeof this._ctx.fillStyle !== 'string') {
console.warn(`Color: ${css} is invalid using fallback ${fallback.css}`);
return fallback;
}
this._ctx.fillRect(0, 0, 1, 1);
const data = this._ctx.getImageData(0, 0, 1, 1).data;
// Check if the printed color was transparent
if (data[3] !== 0xFF) {
if (!allowTransparency) {
// Ideally we'd just ignore the alpha channel, but...
//
// Browsers may not give back exactly the same RGB values we put in, because most/all
// convert the color to a pre-multiplied representation. getImageData converts that back to
// a un-premultipled representation, but the precision loss may make the RGB channels unuable
// on their own.
//
// E.g. In Chrome #12345610 turns into #10305010, and in the extreme case, 0xFFFFFF00 turns
// into 0x00000000.
//
// "Note: Due to the lossy nature of converting to and from premultiplied alpha color values,
// pixels that have just been set using putImageData() might be returned to an equivalent
// getImageData() as different values."
// -- https://html.spec.whatwg.org/multipage/canvas.html#pixel-manipulation
//
// So let's just use the fallback color in this case instead.
console.warn(
`Color: ${css} is using transparency, but allowTransparency is false. ` +
`Using fallback ${fallback.css}.`
);
return fallback;
}
let r: number;
let g: number;
let b: number;
let a: number;
let rgba: number;
if (css.length === 5) {
const num = parseInt(css.substr(1), 16);
r = ((num >> 12) & 0xF) * 16;
g = ((num >> 8) & 0xF) * 16;
b = ((num >> 4) & 0xF) * 16;
a = (num & 0xF) * 16;
rgba = toRgba(r, g, b, a);
} else {
rgba = parseInt(css.substr(1), 16);
r = (rgba >> 24) & 0xFF;
g = (rgba >> 16) & 0xFF;
b = (rgba >> 8) & 0xFF;
a = (rgba ) & 0xFF;
}
return {
rgba,
css: toCss(r, g, b, a)
};
}
return {
css,
rgba: toRgba(data[0], data[1], data[2], data[3])
};
}
}