1. A method for projecting images using two or more projectors onto a three-dimensional surface to alter the appearance of the three-dimensional surface comprising: modeling a defocus of each projector of the two or more projectors, wherein the model is independent of a location of the three-dimensional surface and a location of each prosector; determining the light transport of the three-dimensional surface; detecting discontinuous projection depths on the three-dimensional surface by using a computer to analyze a three-dimensional mesh corresponding to the three-dimensional surface; adjusting by the computer a first input image and a second input image to create a first modified image and a second modified image based on the defocus of each projector; the light transport of the three-dimensional surface; and a characteristic of the first input image and the second input image at a location of the discontinuous regions; and projecting the first modified image and the second modified image onto the three-dimensional surface.