Noise that is independant of block

[tricky]

I have an office building whose windows are models as blocks in AutoCAD. We are file-linking this model into Max. Therefore, all UVW mapping that is applied to one window will be repeated, exactly, on every reference of that block.

However, I want to put a noise bump map in the glass material so that the reflections aren't too perfect.

The problem is that the same bump pattern will be copied from window to window so they will all look the same.

Is there a way to apply a noise-based bump map to all the windows so that they are all slightly different? I don't want to bind the file linked geometry as then updates in AutoCAD will be broken.

[instinct]

Using worldspace mapping should do the trick.

Regards,
Thorsten

[tricky]

Of course! How did I miss that??? Thanks Thorston.