When you set a vectorial fill to a surface material you can only set the pen colour for the hatch itself - not the background of the fill.
The background comes from the elevation settings.
You can choose to set a uniform pen colour for all uncut surfaces in which case all walls will appear the same colour.
Or you can choose the option to use "own surface colour" in which case it will use the surface colour you set in the surface settings (internal or OpenGL settings).
This means though you will need to set up multiple surfaces all with a different shade of colour and apply the different surfaces to each of your walls.
Then print in grey scale (not black and white).
Barry.
One of the forum moderators.
Versions 6.5 to 27
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