Image-based Real-time Hatching of Scene Traveling

Abstract

Real-time rendering of a complete 3D scene with hatching strokes is an important direction in NPR field. In this paper, a comprehensive solution is presented to render complicate scenes with pen-and-ink style in real time. With the help of powerful programmable graphics hardware, our real-time system includes many features as hatching, continuous tones, silhouettes, and shadows. We build our approach in image-space, while allowing for the stroke directions and frame coherence. In our method, various features of pen-and-ink drawings are derived from 3-D information through multi-pass rendering. After synthesis, the desired shading tone is achieved by mapping preprocessed stroke textures to the screen. As a tip for saving texture memory, we prepare a few stroke textures with only certain tones and directions, and compose requisite stroke types in real time. Furthermore, we develop some forms of “indication” to convey the impression of a texture without drawing every single stroke, which makes the result look more natural and art-stylized.