I been working with bryce for a little more than two years and now I discovered the versitility of terrains. I just never went there....  for all of you that already knew how to do this hope you have a good laugh.  But for those that did not know,,,,,

In short,  here is what I did..  I made a bump drawing in Painter saved it as a JPG.  Use what ever software you like to make your bump...

Opened Bryce 5.5 in my case,,,   Clicked on a terrain, with the terran highlighted  I cliked on the "E" tab (editor)  opened the Terrain Editor and in the 'Editing Tool' > got to pictures > click on load>  got my JPG bump....  and clicked open...  you should see it now in the Terrain Canvas and the 3D preview..  click the check mark to accept and exit the editor and it should appear in the Bryce screen... but the terrai is stll horizontal...

It might be a little stretched out in thicknes (very spikee) and not look like your wall bump but this is quickly fixed by making the object's box thinner in the bryce main screen using its control handles....

Turn the terrain vertical adjust it as neede and you got a 3D wall.  just copy and paste an entire wall.  You can make the bump into any type of wall you like.....
see image of both bump and terrain output...  let me know if I made sense,,,,

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