zent/src/colorpicker/helpers/checkboard.ts

一套前端设计语言和基于React的实现

import createElement from '../../utils/dom/createElement';

const checkboardCache = {};

export function render(c1, c2, size, ServerCanvas) {
  if (typeof document === 'undefined' && !ServerCanvas) return null;
  const canvas = ServerCanvas ? new ServerCanvas() : createElement('canvas');
  canvas.width = size * 2;
  canvas.height = size * 2;
  const ctx = canvas.getContext('2d');
  if (!ctx) return null; // If no context can be found, return early.
  ctx.fillStyle = c1;
  ctx.fillRect(0, 0, canvas.width, canvas.height);
  ctx.fillStyle = c2;
  ctx.fillRect(0, 0, size, size);
  ctx.translate(size, size);
  ctx.fillRect(0, 0, size, size);
  return canvas.toDataURL();
}

export function get(c1, c2, size, serverCanvas) {
  const key = `${c1}-${c2}-${size}${serverCanvas ? '-server' : ''}`;
  const checkboard = render(c1, c2, size, serverCanvas);

  if (checkboardCache[key]) {
    return checkboardCache[key];
  }
  checkboardCache[key] = checkboard;
  return checkboard;
}