cam_pos      = [0.46614, 1.28133, -0.414413]';
cam_dir      = [-0.953087, -0.280348, -0.114149]';
cam_up       = [-0.271262, 0.958392, -0.0888962]';
cam_lookat   = [0, 0, 1]';
cam_sky      = [0, 1, 0]';
cam_right    = [-0.178647, 0.0715029, 1.31601]';
cam_fpoint   = [0, 0, 1]';
cam_angle    = 90;