Overview of WebGL rendering pipelines and culling algorithms

Scene culling works

Removal of the optic cone
- Generally, it traverses the six surfaces of the visual vertebral body, and calculates the minimum distance from the center of the object to the surface (with positive and negative directions) and compares it with the radius of the surrounding sphere. If it is smaller than the radius, it means it is outside.
Viewport culling (Render pipeline – Pixel Assembly (cropping))
Back cull (Render pipeline – Pixel assembly (back cull))
Early Z Culling(Rendering Pipeline — Testing (Depth testing))
Distance to eliminate
- Judging whether the object is removed by the distance between the object and the camera, the principle is relatively simple, and the removal efficiency is relatively high. In UE4, the maximum and minimum distances to be removed can be set by object attributes (as shown below) :
Block out
- Screened out after excluding refers to the camera, directly within the scope, there are still many body has obscured the relationship, don’t need to do a rendering, although gpu has depth test, the object will be covered for, but we still hope to keep out before submission to gpu to judge, out something ahead of time, reducing the pressure of rendering.
Occlusion Query
Hiz Culling(don’t understand)
PVS (not understand)

The original