cam_pos      = [-0.0454318, 1.62184, 0.862567]';
cam_dir      = [-0.722237, 0.166099, 0.671405]';
cam_up       = [-0.347094, 0.752607, -0.559561]';
cam_lookat   = [0, 0, 1]';
cam_sky      = [0, 1, 0]';
cam_right    = [0.795667, 0.847445, 0.646259]';
cam_fpoint   = [0, 0, 1]';
cam_angle    = 90;