Fully analytic shading model with specular reflections for polygon-based hologram

For polygon-based holograms, the efficiency of the fully analytical algorithm is outstanding compared with that of the spectral interpolation-based method. However, the full analytical algorithm is not beneficial for the rendering of objects, owing to the uniform amplitude of each triangle. In this paper, we propose a shading rendering method based on a fully analytical spectrum. We used the Blinn-Phong reflection model to simulate a scene with realistic lighting and render a glossy, smooth object surface without changing the number of polygons sampled. The proposed method develops approximate exponential functions to replace cumbersome diffuse and specular reflections, allowing us to derive fully analytical spectra. The computational results for several 3D objects show that the proposed method is highly efficient and presents realistic illumination effects owing to the analytical equations.