Technology Based On The Surface Details Of The Relief Maps Drawn

Along with the boosting of the Digital Media Technology, 3D Graphics Technology of computer has been rapidly developed. It is one of the most active fields in the computer science. The main research content of computer graphics is how to express graphics and study the relevant principles and algorithms of calculating, displaying and showing the graphics using computer. 3D Graphics is wildly used in many aspects of society such as Network Game, Military Training and Virtual Reality.In 2003, the core study of 3D game engine was placed on the agenda of the 863 plan. The 3D game engine plays a important role in games. In the rending, the application of texture mapping can strengthen the reality and increase the rendering speed of the scene. Especially the advanced texture mapping technique such as bump mapping play an irreplaceable role in improving the reality of scene.In recent years, bump mapping is a hotspot in 3D graphics, which is mainly used to render the surface detail, making the object surface look rough, and increase the reality of the scene. The presence of geometric details on object surfaces dramatically changes the way light interacts with these surfaces. Although synthesizing realistic pictures requires simulating this interaction as faithfully as possible, explicitly modeling all the small details tends to be impractical. To address these issues, an image-based technique called relief mapping has recently been introduced. This thesis presents a technique for mapping relief textures onto arbitrary polygonal models in real time. The surface details are informed as depth maps, leading to a technique with very low memory requirements and not involving any changes of the model's original geometry. The algorithm is performed in image space and can be efficiently implemented on current GPUs, allowing extreme close-ups of both the surfaces . The mapped details exhibit correct self-occlusions, shadows and interpenetrations.This thesis firstly introduces the background, significance and the purpose of this topics and briefly introduces the 3D graphics engine. Secondly, it introduces the texture mapping techniques. Then this thesis mainly introduces the key technologies of bump mapping, including normal mapping, parallax mapping. Then it gives a detailed explain for relief mapping algorithm. In this chapter, firstly compare the several methods of searching for the ray-height-filed intersection. And then this thesis propose a method for increased precision of ray-height-field intersection. Then, this thesis introduces a method using penumbra approximation technique to generate self-shadows. The render effect using this technique is better that compute the self-shadows by estimating light visibility for the displaced surfaces. Finally, this thesis gives some pictures implemented using the system.