group() {
	square(size = [1, 1], center = false);
	multmatrix([[1, 0, 0, 2], [0, 1, 0, 0], [0, 0, 1, 0], [0, 0, 0, 1]]) {
		square(size = [1, 1], center = true);
	}
	multmatrix([[1, 0, 0, 4], [0, 1, 0, 0], [0, 0, 1, 0], [0, 0, 0, 1]]) {
		square(size = [1, 1], center = true);
	}
	multmatrix([[1, 0, 0, 6], [0, 1, 0, 0], [0, 0, 1, 0], [0, 0, 0, 1]]) {
		square(size = [0, 0], center = true);
	}
	multmatrix([[1, 0, 0, 0], [0, 1, 0, 2], [0, 0, 1, 0], [0, 0, 0, 1]]) {
		square(size = [1, 0], center = true);
	}
	multmatrix([[1, 0, 0, 2], [0, 1, 0, 2], [0, 0, 1, 0], [0, 0, 0, 1]]) {
		square(size = [0, 1], center = true);
	}
	multmatrix([[1, 0, 0, 4], [0, 1, 0, 2], [0, 0, 1, 0], [0, 0, 0, 1]]) {
		square(size = [1, 2], center = true);
	}
	multmatrix([[1, 0, 0, 6], [0, 1, 0, 2], [0, 0, 1, 0], [0, 0, 0, 1]]) {
		square(size = [2, 1], center = true);
	}
}