Implementing the glTF2 shading model
This recipe will cover how to integrate a PBR into your graphics pipeline. Since the topic of PBR rendering is vast, we focus on a minimalistic implementation just to guide you and get you started. In the book text right here, we focus on the GLSL shader code for the PBR shading model and use OpenGL to make things simpler. However, the source code bundle for this book contains a relatively small Vulkan implementation that reuses the same GLSL code. Indeed, rendering a physically based image is nothing more than running a fancy pixel shader with a set of textures.
Getting ready
It is recommended to read about glTF 2.0 before you proceed with this recipe. A lightweight introduction to the glTF 2.0 shading model can be found at https://github.com/KhronosGroup/glTF-Sample-Viewer/tree/glTF-WebGL-PBR.
The C++ source code for this recipe is in the Chapter6/GL01_PBR folder. The GLSL shader code responsible for PBR calculations can be found in data...
