cam_pos      = [0.477553, 1.65608, 0.313685]';
cam_dir      = [0.405061, 0.2245, -0.886299]';
cam_up       = [-0.0616122, 0.973884, 0.218527]';
cam_lookat   = [0, 0, 1]';
cam_sky      = [0, 1, 0]';
cam_right    = [-1.21324, 0.0451003, -0.543058]';
cam_fpoint   = [0, 0, 1]';
cam_angle    = 90;