“Real-Time Rendering of Billboard Plants in a Dynamic Lighting Environment1”

Realistic rendering of nature is still a very challenging task. Even a small part of a forest includes thousands of trees, shrubs and other plants. To achieve real-time rates it is necessary to use very simplified models. Since the foliage consists of many arbitrary orientated elements, standard level of detail methods producing inaccurate results. Decoret et al. [Decoret et al. 2003] introduced billboard ́ clouds to reduce the complexity of polygonal models. A modified version of this approach can be used for plants as well. A tree is converted into a collection of billboards, that are representing individual parts of the original object. This method however leads to problems when rendering the new models, because the position and normal of the elements were changed during the creation process. In our sketch we present a new approach to render billboard plants in a dynamic low-frequency lighting environment. A additional illumination texture enables us to include many lighting effects like self-shadowing or subsurface scattering in real-time.

Décoret, X., Durand, F., Sillion, F. X., and Dorsey, J. 2003. Billboard clouds for extreme model simplification. ACM Trans. Graph. 22, 3, 689–696.
Franzke, O., and Deussen, O. 2003. Rendering plant leaves faithfully. In SIGGRAPH ’03: Proceedings of the SIGGRAPH 2003 conference on Sketches & applications, ACM Press, 1–1.
Sloan, P.-P., Kautz, J., and Snyder, J. 2002. Precomputed radiance transfer for real-time rendering in dynamic, low-frequency lighting environments. In SIGGRAPH ’02: Proceedings of the 29th annual conference on Computer graphics and interactive techniques, ACM Press, 527–536.