@thi.ng/text-canvas/rect.js

Text based canvas, drawing, plotting, tables with arbitrary formatting (incl. ANSI/HTML)

import { peek } from "@thi.ng/arrays/peek";
import { NONE } from "@thi.ng/text-format/api";
import { hline, vline } from "./hvline.js";
import { charCode } from "./utils.js";
const clear = (canvas, reset = false, code = 32) => {
  const rects = canvas.clipRects;
  if (reset) {
    rects.length = canvas.styles.length = 1;
    canvas.format = canvas.defaultFormat;
  }
  code = charCode(code, canvas.format);
  if (rects.length > 1) {
    const { x1, y1, w, h } = peek(rects);
    fillRect(canvas, x1, y1, w, h, code);
  } else {
    canvas.data.fill(code);
  }
};
const clearFormat = ({ data }, format = NONE) => {
  format <<= 16;
  for (let i = data.length; i-- > 0; ) data[i] = data[i] & 65535 | format;
};
const fillRect = (canvas, x, y, w, h, char, format = canvas.format) => {
  x |= 0;
  y |= 0;
  w |= 0;
  h |= 0;
  const { x1, y1, x2, y2 } = peek(canvas.clipRects);
  if (x < x1) {
    w += x - x1;
    x = x1;
  }
  if (y < y1) {
    h += y - y1;
    y = y1;
  }
  const { data, width } = canvas;
  if (w < 1 || h < 1 || x >= x2 || y >= y2) return;
  w = Math.min(w, x2 - x);
  h = Math.min(h, y2 - y);
  char = charCode(char, format);
  for (; h-- > 0; y++) {
    const idx = x + y * width;
    data.fill(char, idx, idx + w);
  }
};
const strokeRect = (canvas, x, y, w, h, format = canvas.format) => {
  w |= 0;
  h |= 0;
  if (w < 2 || h < 2) return;
  const style = peek(canvas.styles);
  hline(canvas, x, y, w, style.tl, style.tr, style.hl, format);
  hline(canvas, x, y + h - 1, w, style.bl, style.br, style.hl, format);
  vline(canvas, x, y + 1, h - 2, void 0, void 0, void 0, format);
  vline(
    canvas,
    x + w - 1,
    y + 1,
    h - 2,
    void 0,
    void 0,
    void 0,
    format
  );
};
export {
  clear,
  clearFormat,
  fillRect,
  strokeRect
};