Abstract : Rendering realistic natural scenes in real-time is a challenging topic in the field of computer graphics. More specifically, we want to render scenes that contain complex shapes bounded in a layer above a surface. Landscapes (e.g., terrain, vegetation) are examples of such scenes. Lightings and shadows are essential elements toward realism because they help understanding shapes. However: - Using polygonal meshes and classical shadowing algorithms are too costly in terms of computation for complex scenes; - Adapted algorithms for dedicated representations such height-fields are efficient, but these representations are too limited for our needs (e.g. forest); - Although more powerful representations like surfels or texels exist, algorithms for quality and efficient lighting and shadowing are not available yet. Thus, our goal is to propose lighting and shadowing techniques adapted to such representations as well as the GPU.