cam_pos      = [-0.870697, 1.64936, 1.29542]';
cam_dir      = [0.968566, -0.00992936, 0.248559]';
cam_up       = [0.107534, 0.917731, -0.38237]';
cam_lookat   = [0, 0, 1]';
cam_sky      = [0, 1, 0]';
cam_right    = [0.298338, -0.528115, -1.18363]';
cam_fpoint   = [0, 0, 1]';
cam_angle    = 90;