Method and system for drawing ambient occlusion images based on GPU (graphic processing unit) acceleration

Abstract

The invention relates to a method and a system for drawing ambient occlusion images based on GPU (graphic processing unit) acceleration. The method comprises the following steps: 1) building a hemispherical camera system consisting of uniformly-distributed cameras in a CPU (central processing unit) processor; 2) selecting a camera to shoot scenes within a certain range around an object to be rendered so as to obtain a scene depth map (with scene depth values) for the scenes within a certain range around the object to be rendered; 3) receiving the vertex data (include a vertex coordinate) of the object to be rendered, and carrying out calculation according to the vertex coordinate so as to obtain the rendering depth value of a pixel; 4) according to the scene depth value and rendering depth value of the pixel, calculating the AO (ambient occlusion) information of the pixel; 5) storing the AO information of the pixel into an AO map according to a pre-generated AO map; and 6) rendering the online scene of the AO map into displayable ambient light, then outputting the displayable ambient light. In the method, because the AO information calculation process is completed in the GPU processor, and the GPU processor has a strong parallel processing capacity, the calculation efficiency is greatly increased.

Description

technical field [0001] The invention relates to the field of computer realistic imaging, in particular to a method and system for rendering an ambient light occlusion image based on GPU acceleration. Background technique [0002] In recent years, computer graphics has developed greatly in many fields such as games, virtual reality, and movie special effects. With the continuous increase of application requirements, people's requirements for realistic graphics are also increasing. Ambient Occlusion (AO, Ambient Occlusion) is an important part of global illumination technology. AO describes the occlusion value of points on the object surface and other objects in the scene. AO is used in global illumination to attenuate the illumination value of the light reaching the surface. , and then generate shadows to increase the realism of graphics. Ambient occlusion technology is a major breakthrough in shadow calculation. By increasing the light and dark levels in the shadow, the lig...

AI Technical Summary

Problems solved by technology

However, the obvious disadvantages of this algorithm are: firstly, the more complex the object model is, the more vertices need to be calculated, and the execution efficiency is O(n); The requirements are higher, rather than pixel-level lighting calculations; finally, because the algorithm has high requirements for logical judgment, it can only be calculated by the CPU processor, and it cannot pass the graphics card with low logical judgment ability but strong parallel processing ability. Graphics processing unit (GPU, Graphic Processing Unit) accelerated processing, unable to take advantage of the rapid performance of the current graphics card, it is not suitable for the next-generation engine currently commonly used

The disadvantage of this method is that, firstly, the complexity of the algorithm is linearly related to the complexity of the object model, the more complex the object model is, the more surfaces need to be calculated; secondly, the algorithm only calculates the ambient light occlusion information of the vertices, and the algorithm is not sensitive to logical judgments. higher requirements, rather than pixel-level lighting calculations; finally, because the algorithm has high requirements for logical judgment, it can only be calculated by the CPU processor, and cannot be calculated by the GPU with low logical judgment ability but strong parallel processing ability. Processor accelerated processing

Images