cam_pos      = [-0.685428, 1.70419, 0.212563]';
cam_dir      = [0.929678, -0.131639, 0.344049]';
cam_up       = [0.0574065, 0.974332, 0.217673]';
cam_lookat   = [0, 0, 1]';
cam_sky      = [0, 1, 0]';
cam_right    = [0.48395, 0.242878, -1.21478]';
cam_fpoint   = [0, 0, 1]';
cam_angle    = 90;