Apparent Motion with Shader Lamps
We have developed a set of techniques to create apparent motion on real objects by projecting real-time animations. This project is based on an extension of the Shader Lamps concept. By introducing  a set of techniques and applications that involve projectors, non-planar surfaces and computer graphics animations, our goal is to demonstrate the use of projectors in a new type of display medium.
Background & Objective: Animations in movies delight the audience with moving characters but they remain on a flat 2D screen. Physical dioramas, on the other hand, are detailed, three-dimensional and allow physical interaction but they are static. Our techniques to combine the two in some limited cases. We illuminate static physical models with projectors. The images are generated with real time three dimensional computer graphics. Our system demonstrates various visual effects such as non-photorealistic shading, apparent motion and virtual lighting on a toy-car model.
Technical Discussion: Projector can be used to change the surface appearance of neutral colored physical models by illuminating them with rendered images. The projectors are treated as ‘Shader Lamps’ [Raskar et al. 2001]. In this type of projector-based augmentation, complete illumination of complex 3D shapes is made possible by rendering geometric models of those shapes from multiple overlapping projectors. The geometric models are pre-authored with detailed color, texture and material properties to reproduce desired surface appearance. Although, reproduction of surface reflectance is well studied, simulating apparent motion from static models remains unexplored.   A great deal of perceptual and physiological research has been conducted to discover the properties of the mechanisms for motion analysis by humans. The illusions are created due to the need to sense retinal motion, and analyze it as quickly as possible. We combine such illusions with 3D dimensional animations to create apparent motion effects that would be otherwise difficult to achieve.
Publications:
Technology Areas:
Graphics
Off the Desktop Interaction and Display
Modification Date: July 7, 2008