cam_pos      = [0.0284981, 1.99721, -0.00545707]';
cam_dir      = [0.66362, -0.229903, 0.711866]';
cam_up       = [-0.15671, 0.887765, 0.4328]';
cam_lookat   = [0, 0, 1]';
cam_sky      = [0, 1, 0]';
cam_right    = [0.972858, 0.530365, -0.735636]';
cam_fpoint   = [0, 0, 1]';
cam_angle    = 90;