Real-Time Rendering Of Large Scale Vegetation Scene

Realistic simulation of large-scale vegetation is an important topic in computer graphics research. It is also a challenging problem as the geometry data of vegetation scene is very large which makes the light and shadow calculation of scene very complex. Grassland and forest scene is an important part of large-scale vegetation scenes. They play a crucial role in generating realistic scenarios which is useful in digital entertainment and virtual reality and military simulation.Single grass leaf is simple in geometry. But there are always a large number of grass leaves, and the grassland scene still contains a lot of data. Forest scene is more complex. If we generate large-scale forest scene by single tree model, the number of geometric point will be very large. To achieve real-time performance in grassland forest scenes rendering, we adopted the method of layered textures to represent the scenes and put forward a series of strategies to optimize the layered textures.For the grassland, we used layered textures to render photorealistic grassland and use vertical textures to make the gap between the layers. We also simulated the dynamic grassland based on shifting the layered textures and accelerated rendering speed by non-uniform layered textures. For the forest scene, we used layered textures to generate it when the camera is far from the scene. In order to optimize the gap between layers, we used multi-angle layered textures and billboard methods to meet all angles observation. At last, noise texture was used to achieve smooth transition of three methods. In addition, we carried out a more realistic simulation of illumination and shadow. Finally, we achieved the real-time rate in realistic vegetation scenes rendered.