Currently, there is a wide disconnection between the real and virtual worlds in computer graphics. Art created with textured paints on canvases have visual effects which naturally supplement simple color. Real paint exhibits shadows and highlights, which change in response to viewing and lighting directions. The colors interact with this environment and can produce very noticeable effects. Additionally, the traditional means of human-computer interaction using a keyboard and mouse is unnatural and inefficient---gestures and actions are not performed on the objects themselves. These visual effects and natural interactions are missing from digital media in the virtual world. The absence of these visual characteristics disconnects users from their content. Our research looks into simulating these missing pieces and reconnecting users. TangiPaint is an interactive, tangible application for creating and exploring digital media. It gives the experience of working with real materials, such as oil paints and textured canvases, on a digital display. TangiPaint implements natural gestures and allows users to directly interact with their work. The Tangible Display technology allows users to tilt and reorient the device and screen to see the subtle gloss, shadow, and impasto lighting effects of the simulated surface. To simulate realistic lighting effects we use a Ward BRDF illumination model. This model is implemented as an OpenGL shader program. Our system tracks the texture and relief of a piece of art by saving topographical information. We implement height fields, normal vectors, and parameter maps to store this information. These textures are submitted to the lighting model that renders a final product. TangiPaint builds on previous work and applications in this area, but is the first to integrate these aspects into a single software application. The system is entirely self-contained and implemented on the Apple iOS platforms, the iPhone, iPad, and iPod Touch. No additional hardware is required and the interface is easy to learn and use. TangiPaint is a step in the direction of interactive digital art media that looks and behaves like real materials.
Library of Congress Subject Headings
Computer graphics--Design; Painting--Interactive multimedia--Design; Application software--Development
Department, Program, or Center
Computer Engineering (KGCOE)
Blatner, Anthony, "TangiPaint: Interactive tangible media" (2011). Thesis. Rochester Institute of Technology. Accessed from
RIT – Main Campus