cam_pos      = [-0.601927, 0.894953, -0.0265545]';
cam_dir      = [-0.128663, 0.168801, -0.977217]';
cam_up       = [0.991684, 0.024966, -0.126255]';
cam_lookat   = [0, 0, 1]';
cam_sky      = [0, 1, 0]';
cam_right    = [-0.00410338, 1.31049, 0.22691]';
cam_fpoint   = [0, 0, 1]';
cam_angle    = 90;