Book Image

Unity 2017 Game Optimization - Second Edition

By : Chris Dickinson
Book Image

Unity 2017 Game Optimization - Second Edition

By: Chris Dickinson

Overview of this book

Unity is an awesome game development engine. Through its massive feature-set and ease-of-use, Unity helps put some of the best processing and rendering technology in the hands of hobbyists and professionals alike. This book shows you how to make your games fly with the recent version of Unity 2017, and demonstrates that high performance does not need to be limited to games with the biggest teams and budgets. Since nothing turns gamers away from a game faster than a poor user-experience, the book starts by explaining how to use the Unity Profiler to detect problems. You will learn how to use stopwatches, timers and logging methods to diagnose the problem. You will then explore techniques to improve performance through better programming practices. Moving on, you will then learn about Unity’s built-in batching processes; when they can be used to improve performance, and their limitations. Next, you will import your art assets using minimal space, CPU and memory at runtime, and discover some underused features and approaches for managing asset data. You will also improve graphics, particle system and shader performance with a series of tips and tricks to make the most of GPU parallel processing. You will then delve into the fundamental layers of the Unity3D engine to discuss some issues that may be difficult to understand without a strong knowledge of its inner-workings. The book also introduces you to the critical performance problems for VR projects and how to tackle them. By the end of the book, you will have learned to improve the development workflow by properly organizing assets and ways to instantiate assets as quickly and waste-free as possible via object pooling.
Table of Contents (17 chapters)
Title Page
About the Author
About the Reviewers
Customer Feedback
Software and Hardware List

Consider using distance-squared over distance

It is safe to say that CPUs are relatively good at multiplying floating-point numbers together, but relatively dreadful at calculating square-roots from them. Every time we ask a Vector3 to calculate a distance with the magnitude property or with the Distance() method, we're asking it to perform a square-root calculation (as per Pythagorean theorem), which can cost a lot of CPU overhead compared to many other types of vector math calculations.

However, the Vector3 class also offers a sqrMagnitude property, which provides the same result as distance, only the value is squared. This means that if we also square the value we wish to compare distance against, then we can perform essentially the same comparison without the cost of an expensive square-root calculation.

For example, consider the following code:

float distance = (transform.position – other.transform.position).Distance();
if (distance < targetDistance) {
  // do stuff

This can be replaced...