cam_pos      = [0.210496, 0.655566, -0.333326]';
cam_dir      = [0.874873, 0.286979, 0.39018]';
cam_up       = [-0.466053, 0.279437, 0.83947]';
cam_lookat   = [0, 0, 1]';
cam_sky      = [0, 1, 0]';
cam_right    = [-0.175399, 1.21864, -0.503033]';
cam_fpoint   = [0, 0, 1]';
cam_angle    = 90;