  This paper proposes a new hybrid algorithm for sampling virtual point light
(VPL). The indirect lighting calculation of the scene is used to distribute the
VPL reasonably. In the process of generating VPL, we divide the scene into two
parts according to the camera position and orientation. The close-range part:
the part that the camera pays attention to. The distant-range part: the part
that the camera does not pay attention to or rarely pays attention to. For the
close-range part, we use a patch-based vPL sampling method to distribute the
VPL as evenly as possible on the patch in the near-field area; for the
distant-range part, we use sparse instant radiosity (IR) for sampling. It turns
out that, in contrast to conventional multiple instant radiance Compared with
the VPL generation algorithm, the method proposed in this paper can greatly
improve the quality of the final result graph when the number of VPLs is the
same; Under the same rendering quality, the rendering speed can be greatly
improved.
