vega-label/src/util/placeAreaLabel/common.js

Label layout transform for Vega dataflows.

export function outOfBounds(x, y, textWidth, textHeight, width, height) {
  let r = textWidth / 2;
  return x - r < 0
      || x + r > width
      || y - (r = textHeight / 2) < 0
      || y + r > height;
}

export function collision($, x, y, textHeight, textWidth, h, bm0, bm1) {
  const w = (textWidth * h) / (textHeight * 2),
        x1 = $(x - w),
        x2 = $(x + w),
        y1 = $(y - (h = h/2)),
        y2 = $(y + h);

  return bm0.outOfBounds(x1, y1, x2, y2)
      || bm0.getRange(x1, y1, x2, y2)
      || (bm1 && bm1.getRange(x1, y1, x2, y2));
}