OpenGL Insights

Efficient Layered Fragment

Buffer Techniques

Pyarelal Knowles, Geoff Leach, and F abio Zambetta

20.1 Introduction

Rasterization typically resolves visible surfaces using the depth buffer, computing just

the front-most layer of fragments. However, some applications require all fragment

data, including those of hidden surfaces. In this chapter, we refer to these data and the

technique to compute them as a layered fragment buffer (LFB). LFBs can be used for

order-independent transparency, multilayer transparent shadow maps, more accurate

motion blur, indirect illumination, ambient occlusion, CSG, and relief imposters.

With the introduction of atomic operation ...