Method for rendering global illumination in computer three-dimensional model

The invention discloses a method for rendering global illumination in a computer three-dimensional model. The method comprises the following steps of 1 reading-in a model file and storing points of the model and triangular face information in a kd-tree partitioned data structure; 2 generating a plurality of light source paths starting from light sources through sampling; sampling finally rendered image planes in batches, sampling a part of points each time, generating viewpoint paths starting from viewpoints at the pixel point positions, selecting a light source path in the step 2, adopting a bidirectional path tracking based path connecting method to perform connection so as to obtain color values of current pixels through calculation and repeating the step till all pixel points on a whole image are sampled; 4 repeating the step 2 and the step 3 till a whole rendering result is acceptable.