group() {
	color([0.666667, 0, 0, 1]) {
		linear_extrude(height = 2, $fn = 0, $fa = 12, $fs = 2, convexity = 10) {
			projection(cut = true, convexity = 0) {
				multmatrix([[1, 0, 0, 0], [0, 1, 0, 0], [0, 0, 1, -30], [0, 0, 0, 1]]) {
					surface(file = "surface_image.png", center = true, invert = false, timestamp = 1576020815);
				}
			}
		}
	}
	color([0.833333, 0, 0, 1]) {
		linear_extrude(height = 4, $fn = 0, $fa = 12, $fs = 2, convexity = 10) {
			projection(cut = true, convexity = 0) {
				multmatrix([[1, 0, 0, 0], [0, 1, 0, 0], [0, 0, 1, -60], [0, 0, 0, 1]]) {
					surface(file = "surface_image.png", center = true, invert = false, timestamp = 1576020815);
				}
			}
		}
	}
	color([1, 0, 0, 1]) {
		linear_extrude(height = 6, $fn = 0, $fa = 12, $fs = 2, convexity = 10) {
			projection(cut = true, convexity = 0) {
				multmatrix([[1, 0, 0, 0], [0, 1, 0, 0], [0, 0, 1, -90], [0, 0, 0, 1]]) {
					surface(file = "surface_image.png", center = true, invert = false, timestamp = 1576020815);
				}
			}
		}
	}
}

