Function getContainerSize

src/helpers/helpers.dom.ts:133–158

(canvas: HTMLCanvasElement, width: number, height: number)

}

function getContainerSize(canvas: HTMLCanvasElement, width: number, height: number): Partial<Scale> {
  let maxWidth: number, maxHeight: number;

  if (width === undefined || height === undefined) {
    const container = canvas && _getParentNode(canvas);
    if (!container) {
      width = canvas.clientWidth;
      height = canvas.clientHeight;
    } else {
      const rect = container.getBoundingClientRect(); // this is the border box of the container
      const containerStyle = getComputedStyle(container);
      const containerBorder = getPositionedStyle(containerStyle, 'border', 'width');
      const containerPadding = getPositionedStyle(containerStyle, 'padding');
      width = rect.width - containerPadding.width - containerBorder.width;
      height = rect.height - containerPadding.height - containerBorder.height;
      maxWidth = parseMaxStyle(containerStyle.maxWidth, container, 'clientWidth');
      maxHeight = parseMaxStyle(containerStyle.maxHeight, container, 'clientHeight');
    }
  }
  return {
    width,
    height,
    maxWidth: maxWidth || INFINITY,
    maxHeight: maxHeight || INFINITY
  };
}

const round1 = (v: number) => Math.round(v * 10) / 10;