Abstract: A Spatial Augmented Reality (SAR) system is described. The SAR system includes a SAR device, such as a computer, and a SAR platform such as a set of projectors and object tracking systems that are used for producing a SAR environment. The SAR device can include a loader for receiving and executing one or more SAR application modules and a SAR engine for receiving the input data and for interfacing between the SAR application modules and the output. The architecture of the SAR engine provides a SAR environment independent interface between the SAR application modules and the projectors and object trackers. The SAR engine is responsible for providing perspectively correct projected images in the SAR environment and performing coordinate transformations, and providing updates to application modules, as well as automating many common tasks.