import numpy as np from math import cos, sin def create_rx(unit_axis: np.ndarray) -> np.ndarray: (a, b, c) = unit_axis.tolist() d = (b ** 2 + c ** 2) ** 0.5 return np.array( [[1, 0, 0, 0], [0, c / d, -b / d, 0], [0, b / d, c / d, 0], [0, 0, 0, 1]] ) def create_ry(unit_axis: np.ndarray) -> np.ndarray: (a, b, c) = unit_axis.tolist() d = (b ** 2 + c ** 2) ** 0.5 return np.array([[d, 0, -a, 0], [0, 1, 0, 0], [a, 0, d, 0], [0, 0, 0, 1]]) def create_rz(angel: float) -> np.ndarray: return np.array( [ [cos(angel), -sin(angel), 0, 0], [sin(angel), cos(angel), 0, 0], [0, 0, 1, 0], [0, 0, 0, 1], ] ) def create_t(axis: np.ndarray) -> np.ndarray: (x1, y1, z1) = axis.tolist() return np.array([[1, 0, 0, -x1], [0, 1, 0, -y1], [0, 0, 1, -z1], [0, 0, 0, 1]]) def rotation(angel: float, axis: np.ndarray, points: np.ndarray): # 依据《计算机图形学》第4版 9.28公式 unit_axis = axis / np.linalg.norm(axis) rz = create_rz(angel) rx = create_rx(unit_axis) ry = create_ry(unit_axis) t = create_t(axis) t_i = np.linalg.inv(t) rx_i = np.linalg.inv(rx) ry_i = np.linalg.inv(ry) r_transform = t_i.dot(rx_i.dot(ry_i.dot(rz.dot(ry.dot(rx.dot(t)))))) expand_point = np.concatenate((points, np.ones((points.shape[0], 1))), axis=1) return r_transform.dot(expand_point.T)