Creation and rendering of realistic trees

Recent advances in computer graphics have produced images approaching the elusive goal of photorealism. Since many natural objects are so complex and detailed, they are often not rendered with convincing fidelity due to the difficulties in succinctly defining and efficiently rendering their geometry. With the increased demand of future simulation and virtual reality applications, the production of realistic natural-looking background objects will become increasingly more important. We present a model to create and render trees. Our emphasis is on the overall geometrical structure of the tree and not a strict adherence to botanical principles. Since the model must be utilized by general users, it does not require any knowledge beyond the principles of basic geometry. We also explain a method to seamlessly degrade the tree geometry at long ranges to optimize the drawing of large quantities of trees in forested areas.