cam_pos      = [-0.496871, 1.72132, 1.67868]';
cam_dir      = [0.916073, -0.380478, -0.126679]';
cam_up       = [0.29112, 0.848234, -0.442433]';
cam_lookat   = [0, 0, 1]';
cam_sky      = [0, 1, 0]';
cam_right    = [-0.366801, -0.490001, -1.18079]';
cam_fpoint   = [0, 0, 1]';
cam_angle    = 90;