Study On Biological Molecular Visualization And Illumination Model

Visualization is the use of computer graphics and image and other related technologies,and the ability to interact processing to convert text data into some kind of graphic or imageinformation in a specific format, and ultimately displayed on a computer screen. Biomolecularstructure visualization uses means of computer graphics and visualization technologies, theanalysis process to achieve protein visualization precise and predictable.Visualizationsoftware development process is generally filtered raw data at the beginning of the nextthrough mapping processing, drawing, display, and then continue to receive feedback.The original three-dimensional coordinate data refers to information stored in the ProteinData Bank with specific text format to save space structure protein molecules. It is a text filein a protein database, each record has a corresponding keycord.Common keywords includesHELIX, SHEET, ATOM and so on. Molecular visualization software common molecularmodel has Cartoon model, Ball and Brick model, Sphere model. In order to show the differentmolecular model, reading the same PDB file need to obtain different information. Forexample, when you draw Cartoon model, three-dimensional space is read mainly α-carbonatom coordinates, draw Sphere model, mainly read each amino acid in the atom, such as α-carbon, oxygen, nitrogen, carbon and other atoms coordinate information. Different molecularmodel, there are also corresponding molecular modeling algorithm. When drawing Cartoonmodel, the core algorithm is all the α-carbon atoms fit on a smooth curve. Hermiteinterpolation function algorithm takes into account as well the position of the front and rearatoms α-carbon atoms. Sphere model drawing, painting at the origin of a unit ball, then theball is moved to the spatial location of the center of the different atoms.In order to better visualize and display Sphere molecular model, add lighting effects isindispensable. The traditional illumination model by means of rendering OpenGL libraryfunctions directly related to the parameters set illumination model, matrix, source information, just give the function parameters, but also realizes that the ambient, diffuse, specularreflection and other basic lighting model. Rendering is now lighting by high-level shadinglanguage GLSL, direct rendering on the GPU, ease the pressure on the CPU. And GLSLprogram can write a file separately, under the premise of the compiled source code, written inGLSL program directly, and therefore make the program written using GLSL has goodportability, the algorithm is relatively simple, fast processing speed, high efficiency,ultimately render output quality pictures.This paper studies Tube molecular model, Sphere molecular model, and on the Spheremodel implements the classic illumination model, and also to achieve a more complexillumination model, such as Phong illumination model, Cook-Torrance lighting model,Impostor Sphere "match-fixing" illumination model.Compare the difference between thesetypes of lighting effects, and finally select the best and the calculation time is relatively shortillumination model.