This demo demonstrates real-time rendering of a hilly meadows and a lake. The terrain uses a Quadtree to cull offscreen geometry and geomipmapping for level of detail with minimal CPU intervention. The water reflects and refracts the scene based on Fresnel's Law. The clouds are created with a ray-marching algorithm that approximates the attenuation of sunlight as it passes through clouds. The skydome is based off the paper "A Practical Analytic Model for Daylight" by Preetham et al, 99. The grass is loosely based off of two GPU Gems papers. As a final touch, I add a full screen glow to the final rendering.

Instructions for use - W,S,A,D navigates the scene. Pressing c will toggle a more computationally efficient, but less cool looking version of the clouds.

Download - Nature Demo (requires Shader Model 3.0 support)