why the directional blur doesn't work well

[hzhao]

Hi, I tried the directional blur But it doesn't work. The code is exactly copied from worldviz document.

import vizfx.postprocess
from vizfx.postprocess.blur import DirectionalBlurEffect
effect = DirectionalBlurEffect(angle=60, distance=40)
vizfx.postprocess.addEffect(effect)

The error message is :
ERROR: 0:9: '-' : wrong operand types no operation '-' exists that takes a left-hand operand of type 'uniform int' and a right operand of type 'const float' (or there is no acceptable conversion)

I tried different input number, eg, 60.0, 40.0, float and int. But it still doesn't work.

But the Gaussian blur works well. and the Zoom blur doesn't work either.

What is wrong?

Thanks!!