Book Image

WebGL Beginner's Guide

Book Image

WebGL Beginner's Guide

Overview of this book

WebGL is a new web technology that brings hardware-accelerated 3D graphics to the browser without installing additional software. As WebGL is based on OpenGL and brings in a new concept of 3D graphics programming to web development, it may seem unfamiliar to even experienced Web developers.Packed with many examples, this book shows how WebGL can be easy to learn despite its unfriendly appearance. Each chapter addresses one of the important aspects of 3D graphics programming and presents different alternatives for its implementation. The topics are always associated with exercises that will allow the reader to put the concepts to the test in an immediate manner.WebGL Beginner's Guide presents a clear road map to learning WebGL. Each chapter starts with a summary of the learning goals for the chapter, followed by a detailed description of each topic. The book offers example-rich, up-to-date introductions to a wide range of essential WebGL topics, including drawing, color, texture, transformations, framebuffers, light, surfaces, geometry, and more. With each chapter, you will "level up"ù your 3D graphics programming skills. This book will become your trustworthy companion filled with the information required to develop cool-looking 3D web applications with WebGL and JavaScript.
Table of Contents (18 chapters)
WebGL Beginner's Guide
Credits
About the Authors
Acknowledgement
About the Reviewers
www.PacktPub.com
Preface
Index

Optimization strategies


If you play a little and increase the value of the global constant NUM_BALLS from 50 to 500, you will start noticing degradation in the frame rate at which the simulation runs as shown in the following screenshot:

Depending on your computer, the average time for the draw function can be higher than the frequency at which the animation timer callback is invoked. This will result in dropped frames. We need to make the draw function faster. Let's see a couple of strategies to do this.

Optimizing batch performance

We can use geometry caching as a way to optimize the animation of a scene full of similar objects. This is the case of the bouncing balls example. Each bouncing ball has a different position and color. These features are unique and independent for each ball. However, all balls share the same geometry.

In the load function, for ch5_BouncingBalls.html we created 50 vertex buffer objects (VBOs) one for each ball. Additionally, the same geometry is loaded 50 times,...