A combination of the Wall Printer idea with a laser and optical scanner.
The laser scanner can scan a wall for minute variations in texture.
The optical scanner picks up the correct color pattern off the wall.
A plotter type device then can excrete the right levels of stucco or faux paint-- theircompetitor, May 08 2004 I don't see plotters crawling over walls. 3-D wallpaper is so much simpler.-- ldischler, May 08 2004 There's definitely engineering challenges to be solved here, but the goal of the idea is to actually copy a wall you've seen somewhere.
Perhaps made to order 3D wallpaper can achieve the same thing simpler, but first it would have to use something similar to the description to pick up the original pattern.-- theircompetitor, May 08 2004 I like the custom-ordered 3d wallpaper idea best, I think. The cost of having a robotic wall plotter do the work would likely be as much or more than having an artist/craftsman do it. Artists are cheap. Equipment is expensive, especially when employed on-site. Plus, I think you could work off of digital photographs of the original... That's how video game artists get their pixels for rendering surfaces.-- justaguy, May 08 2004 random, halfbakery