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

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

import { peek } from "@thi.ng/arrays/peek";
import { clamp0 } from "@thi.ng/math/interval";
import { wordWrapLines } from "@thi.ng/strings/word-wrap";
import {
  beginClip,
  beginStyle,
  endClip,
  endStyle
} from "./canvas.js";
import { fillRect, strokeRect } from "./rect.js";
const textLine = (canvas, x, y, line, format = canvas.format) => {
  x |= 0;
  y |= 0;
  const { x1, y1, x2, y2 } = peek(canvas.clipRects);
  if (y < y1 || y >= y2 || x >= x2) return;
  let i = 0;
  if (x < x1) {
    i = x1 - x;
    x = x1;
  }
  const { data, width } = canvas;
  const n = line.length;
  format <<= 16;
  for (let idx = x + y * width; i < n && x < x2; i++, x++, idx++) {
    data[idx] = line.charCodeAt(i) | format;
  }
};
const textLines = (canvas, x, y, lines, format = canvas.format) => {
  for (let line of lines) {
    textLine(canvas, x, y, line, format);
    y++;
  }
  return y;
};
const textColumn = (canvas, x, y, width, txt, format = canvas.format, hard = false) => {
  x |= 0;
  y |= 0;
  width |= 0;
  const height = canvas.height;
  for (let line of wordWrapLines(txt, { width, hard })) {
    textLine(canvas, x, y, line.toString(), format);
    y++;
    if (y >= height) break;
  }
  return y;
};
const textBox = (canvas, x, y, width, height, txt, opts = {}) => {
  const {
    format = canvas.format,
    hard = false,
    padding: [padX, padY] = [0, 0],
    style
  } = opts;
  const currFmt = canvas.format;
  canvas.format = format;
  style && beginStyle(canvas, style);
  x |= 0;
  y |= 0;
  width |= 0;
  let innerW = width - 2 - 2 * padX;
  let innerH = 0;
  const lines = wordWrapLines(txt, { width: innerW, hard }).map(
    (l) => l.toString()
  );
  if (height < 0) {
    innerH = lines.length + 2;
    height = innerH + 2 * padY;
  } else {
    innerH = clamp0(height - 2);
  }
  strokeRect(canvas, x, y, width, height);
  fillRect(canvas, x + 1, y + 1, width - 2, height - 2, " ");
  x += 1 + padX;
  y += 1 + padY;
  beginClip(canvas, x, y, innerW, innerH);
  y = textLines(canvas, x, y, lines);
  endClip(canvas);
  style && endStyle(canvas);
  canvas.format = currFmt;
  return y + height;
};
export {
  textBox,
  textColumn,
  textLine,
  textLines
};