Approximating global illumination on mesostructure surfaces with height gradient maps

Rendering global illumination for objects with mesostructure surfaces is a time-consuming task, and cannot presently be applied to interactive graphics. This paper presents a real-time rendering method based on a mesostructure height gradient map (MHGM) to exhibit lighting effects on meso-scale details in dynamic environments. We approximate global illumination using a lighting model including three components: incident ambient light, direct light and single bounce indirect light. MHGM is introduced to create local apex sets, which would help us to compute the three components adaptively. Our approach runs entirely on the graphics hardware, and uses deferred shading and the graphics pipeline to accelerate computation. We achieve high quality results which can render meso-scale details with approximate global illumination even for low-resolution geometric models. Moreover, our approach fully supports dynamic scenes and deformable objects.