cam_pos      = [-0.324956, 1.74338, 1.8252]';
cam_dir      = [0.839517, -0.456417, -0.294778]';
cam_up       = [0.282506, 0.830113, -0.480732]';
cam_lookat   = [0, 0, 1]';
cam_sky      = [0, 1, 0]';
cam_right    = [-0.61727, -0.426007, -1.09836]';
cam_fpoint   = [0, 0, 1]';
cam_angle    = 90;