Book Image

GLSL Essentials

By : Jacobo Rodriguez
Book Image

GLSL Essentials

By: Jacobo Rodriguez

Overview of this book

Shader programming has been the largest revolution in graphics programming. OpenGL Shading Language (abbreviated: GLSL or GLslang), is a high-level shading language based on the syntax of the C programming language.With GLSL you can execute code on your GPU (aka graphics card). More sophisticated effects can be achieved with this technique.Therefore, knowing how OpenGL works and how each shader type interacts with each other, as well as how they are integrated into the system, is imperative for graphic programmers. This knowledge is crucial in order to be familiar with the mechanisms for rendering 3D objects. GLSL Essentials is the only book on the market that teaches you about shaders from the very beginning. It shows you how graphics programming has evolved, in order to understand why you need each stage in the Graphics Rendering Pipeline, and how to manage it in a simple but concise way. This book explains how shaders work in a step-by-step manner, with an explanation of how they interact with the application assets at each stage. This book will take you through the graphics pipeline and will describe each section in an interactive and clear way. You will learn how the OpenGL state machine works and all its relevant stages. Vertex shaders, fragment shaders, and geometry shaders will be covered, as well some use cases and an introduction to the math needed for lighting algorithms or transforms. Generic GPU programming (GPGPU) will also be covered. After reading GLSL Essentials you will be ready to generate any rendering effect you need.
Table of Contents (13 chapters)

Summary


In this chapter, we have learnt the basic concepts of compute shaders. As said, they are a complex topic, mainly because of the manual synchronization that must be done to ensure correct results and high performance. We only saw a humble mechanism for that: the glMemoryBarrier function which blocks execution until certain operations have finished, but there are many others, even inside the shaders (atomic operations and counters, control barriers, and so on).

It's up to you to discover more about compute shader features such as shared memory access for the work items inside a work group or how to use buffers with complex data structures in conjunction with images to create amazing shaders. You can also learn how to perform pure mathematical functions such as Fast Fourier Transformations or LU/SVD decompositions to make mathematical algorithms two orders of magnitude faster than doing it simply in CPU.

To conclude this book, I would encourage you to start writing your own shaders, slowly...