In the previous chapter, we covered the history of WebGL, along with its evolution. We discussed the fundamental elements in a 3D application and how to set up a WebGL context. In this chapter, we will investigate how geometric entities are defined in WebGL. 

WebGL renders objects following a "divide and conquer" approach. Complex polygons are decomposed into triangles, lines, and point primitives. Then, each geometric primitive is processed in parallel by the GPU in order to create the final scene.

In this chapter, you will:

• Understand how WebGL defines and processes geometric information
• Discuss the relevant API methods that relate to geometry manipulation
• Examine why and how to use JavaScript Object Notation (JSON) to define, store, and load complex geometries
• Continue our analysis of WebGL as a state machine to describe the attributes that are relevant to geometry manipulation that can be set and retrieved
• Experiment with creating and loading different geometry models