A radiosity solution for curved surface environments
Tóm tắt
Radiosity has been a popular method for photorealistic image generation. But the determination of form factors between curved patches is the most difficult and time consuming procedure, and also the errors caused by approximating source patch’s radiosity with average values are obvious. In this paper, a radiosity algorithm for rendering curved surfaces represented by parameters is described. The contributed radiosity from differential areas on four vertices of the source patch to a receiving point is calculated firstly, then the contribution from the inner area of the source patch is evaluated by interpolating the values on four corners. Both the difficult problem of determining form-factors between curved surfaces and errors mentioned above have been avoided. Comparison of the experimental results using the new algorithm has been made with the ones obtained by traditional method. Some associated techniques such as the visibility test and the adaptive subdivision are also described.
Tài liệu tham khảo
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