Interactive Appearance Manipulation of Fiber-based Materials

Achieving a visually appealing experience for the user interaction with photo-realistic digitized micro-fiber materials is a challenging task. While state-of-the-art high-quality fabric modeling techniques rely on complex micro-geometry representations that are computationally expensive and not well-suited for interactive rendering, previous interactive reflectance models reach a speed-up at the cost of discarding many of the effects of light exchange that significantly contribute to the appearance of fabric materials. In this paper, we present a novel, example-based technique for the interactive manipulation of micro-fiber materials based on bidirectional texture functions (BTFs) that allow considering fine details in the surface reflectance behavior. BTFs of the respective material sample are acquired for varying fiber orientations and combined to a single texture representation that encodes material appearance depending on the view and light conditions as well as the orientations of the fibers. This model can be efficiently evaluated depending on the user input which, as demonstrated by our results, allows a realistic simulation of the interaction with micro-fiber materials in