Another test, this time of the abbey ruins that's appeared in other posts, sun at 75° to check the lighting effects.
I replaced the default shader for the bricks to a surface shader with a couple of image shaders. Displacement is 0.1, masked by a modified bump map supplied with the model, and the brick textures are scaled to 0.3 and tiled.
It's unfortunate that the add ons to the wall which help break up the shape so well use the same surface as the wall. I'll check the groups in PoseRay to see if there's an easy workaround (otherwise it's beyond my skills/software). The original bump map is a bit of a hack, being derived just from the texture image, but at a medium distance it looks reasonable effective.
