const COLUMNS = 5;
const ROWS = 5;
const CELL_WIDTH = 32;
const CELL_HEIGHT = 32;

function updateAnchor(anchor, index) {
	const column = (index - 1) % COLUMNS;
	const row = Math.floor((index - 1) / COLUMNS);
	return {
		// Outputs -64, -64, -64, ...
		x: column * CELL_WIDTH - (COLUMNS - 1) * CELL_WIDTH / 2,
		// Outputs -64, -32, -0, ...
		y: row * CELL_HEIGHT - (ROWS - 1) * CELL_HEIGHT / 2,
	};
}