Chapter 13. Indoors Rendering

"His house was perfect, whether you wanted food, or sleep, or work, or story-telling, or singing, or just sitting and thinking, best, or a pleasant mixture of them all."

—J. R. R. Tolkien, The Fellowship of the Ring

KEY TOPICS

• General Analysis

• Occluder-Based Algorithms

• Binary Space Partition Algorithms

• Portal Rendering

• Hierarchical Occlusion Maps

• Hybrid Approaches

• Hardware-Assisted Occlusion Tests

• In Closing

Indoors rendering has been a popular technique for game development ever since Wolfenstein 3D by id Software was released. Games taking place inside buildings have become widespread; their visual appeal increasing with each new hardware iteration or engine release. In this chapter, we will explore the building blocks for any indoors engine. Three popular approaches—Binary Space Partitions (BSPs), portal rendering, and octree rendering—will be explored in full, and some specialized solutions will be covered thereafter. As you will soon discover, indoors games often require quite complex techniques.