function make_monochrome_palette(rgba1 = [0, 0, 0, 255], rgba2 = [255, 255, 255, 255]) {
	const palette = [];
	const n_colors_per_row = 14;
	const n_colors = n_colors_per_row * 2;
	for (let i = 0; i < n_colors_per_row; i++) {
		let lightness = i / n_colors;
		palette.push(make_monochrome_pattern(lightness, rgba1, rgba2));
	}
	for (let i = 0; i < n_colors_per_row; i++) {
		let lightness = 1 - i / n_colors;
		palette.push(make_monochrome_pattern(lightness, rgba1, rgba2));
	}

	return palette;
}
@param {Uint8ClampedArray | number[]} rgba1
@param {Uint8ClampedArray | number[]} rgba2
@returns {CanvasPattern[]}