Research And Implementation On Critical Technique Of Virtual Reality

The critical technique of virtual reality, the modeling transformation in virtual scenes and the hidden technique on 3D objects are discussed in this thesis. Firstly, the geometry construction in the method and tools of 3D construction is mainly discussed. Secondly, by taking advantage of line drawing technique, a method of modeling construction based on photo, which realizes the modeling of simple object is presented. Thirdly, the principles of NURBS curve and surface are used to the modeling of complex object, and a protruding quadratic programming algorithm for reconstructing reference points of NURBS curve. In order to assure 3D of the scenes, the method and application of hidden line and hidden surface elimination in virtual reality are briefly reviewed, including the render of the single planar convex using Roberts method, the render of more than one convex overlapping each other using reformative drawer algorithm and the render of the free-form surface using skinning approach. On the basis of analyzing skinning method in detail, the measure is predigested contraposing existent problems. And by combining the advantage of the NURBS technology, a method called the floating planar transversal is used to realize the free hidden-surface removal and protraction. In this thesis a plenty of research and experiment works are done, and the result is perfect.