The Wide Area Virtual Environment (WAVE) is an 8,000 sq. ft. virtual reality facility for medical team-based training. A high resolution tiled stereoscopic display, involving an array of 48 projectors, creates an immersive environment. Projector alignment is critical to the training experience. However, frequent projector image drifting makes it difficult to maintain alignment. The need for a permanently installed solution, and the unique shape of the tiled display imposes difficulties in employing other methods. This paper describes a scalable image warping method developed to automate projector alignment. The multi-threaded and distributed approach makes very frequent alignments possible via a tablet and inexpensive webcams.