cam_pos      = [-0.583967, 1.93613, 0.0870115]';
cam_dir      = [0.838638, -0.169495, 0.517647]';
cam_up       = [0.0369229, 0.965856, 0.256436]';
cam_lookat   = [0, 0, 1]';
cam_sky      = [0, 1, 0]';
cam_right    = [0.722771, 0.260604, -1.08563]';
cam_fpoint   = [0, 0, 1]';
cam_angle    = 90;