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About this book

This is the first book to offer a comprehensive overview for anyone wanting to understand the benefits and opportunities of ray tracing, as well as some of the challenges, without having to learn how to program or be an optics scientist.

It demystifies ray tracing and brings forward the need and benefit of using ray tracing throughout the development of a film, product, or building — from pitch to prototype to marketing.

Ray Tracing and Rendering clarifies the difference between conventional faked rendering and physically correct, photo-realistic ray traced rendering, and explains how programmer’s time, and backend compositing time are saved while producing more accurate representations with 3D models that move.

Often considered an esoteric subject the author takes ray tracing out of the confines of the programmer’s lair and shows how all levels of users from concept to construction and sales can benefit without being forced to be a practitioner.

It treats both theoretical and practical aspects of the subject as well as giving insights into all the major ray tracing programs and how many of them came about.

It will enrich the readers’ understanding of what a difference an accurate high-fidelity image can make to the viewer — our eyes are incredibly sensitive to flaws and distortions and we quickly disregard things that look phony or unreal. Such dismissal by a potential user or customer can spell disaster for a supplier, producer, or developer. If it looks real it will sell, even if it is a fantasy animation.

Ray tracing is now within reach of every producer and marketeer, and at prices one can afford, and with production times that meet the demands of today’s fast world.

Table of Contents

Frontmatter

Chapter 1. Preface

Abstract
The goal of this book is to explain the many methods of rendering a digital image in a computer and what is ray tracing. Ray tracing is one part of the continuum of rendering solutions on the path to a perfect photorealistic image. Ray tracing has several cousins with a similar name such as Path Tracing and ray casting, which sometimes get used interchangeably; that is not correct and can be confusing. One of the objectives of this book is to establish clear delineation between those other technologies whose only common element is a word, but not the technology, algorithm, or result. Ray tracing holds the promise of providing us with the most cost-effective photorealistic images possible. The process has been criticized for being such an enormous consumer of computer resources, but new developments in hardware and algorithms are changing that and making real-time ray tracing not only possible but practical.
Jon Peddie

Chapter 2. Introduction

Abstract
Ray tracing isn’t new, nor is it the end-point in realistic, physically accurate rendering. In fact, it is a subset of global illumination, and partner with ray-casting, path-rendering, and other techniques. Ray tracing can be traced back to the 1950s, and even further, but it came into its own in the 1980s with the development of faster computers, more of them, and new algorithms and discoveries. As with many technologies, it got its start due to military research.
Jon Peddie

Chapter 3. The Rendering Industry

Abstract
The rending industry, and ray tracing specifically is an enigma in that it looks like a start-up industry with dozens of supplies making it ripe for consolidation, and yet it’s been in existence since the mid-1980s—hardly a start-up situation. That is partially due to the relative ease of generating a ray tracing program—the math is very straight forward and easy to understand and code. But more so because of the quest for efficiency and the unending demand for material libraries. One of the reasons there are so many ray tracing programs available is because of the industry-specific material libraries each program has. Big companies with CAD and 3D modeling main-line programs will have two to four in-house ray tracing programs of their own, plus a half dozen plug-ins that work with the main program. It’s not uncommon for a studio for example to employ four to six different ray tracing programs in the production of the movie, using each one for a particular look.
Jon Peddie

Chapter 4. The Continuum

Abstract
The use of a computer to generate a simulated image can be traced back to the first games and CAD programs in the late 1970s. Simulations of weather maps, circuit boards, mechanical drawing of automobiles (actually dating back to the early 1960s) show the interest and unending quest for a faithful representation of a physical thing, or a fantasy thing. Over the decades, brilliant computer scientists from various disciplines as diverse as geographical information systems to movie animations, and CAD drawings for giant buildings, bridges, and space ships came up with clever ways to create amazing looking images—but they were for the most part trickery, and not faithful to the physics of light. The difference between a physically accurate photorealistic image and a clever approximation in terms of computing workload is 100–10000 times. It is almost a law that as soon as new more accurate rendering technique is developed, the workload to use it goes up by orders of magnitude. Then, other clever researchers figure out ways to do it more efficiently and the process becomes affordable in time and hardware and is adopted for everyday use. That process is a continuum and doesn’t indicate any end point.
Jon Peddie

Chapter 5. Work Flow and Material Standards

Abstract
Although the basic ray racing algorithm is relatively straight forward, the supporting components to produce a high-quality ray traced image are formidable. How long an image is allowed to take to resolve brings into question the degree of accuracy and fidelity desired, or acceptable. If a rendering is halted before it is fully resolved, some practitioners says such a compromise results in a biased image. Standards in libraries, APIs, shading languages and colors to mention a few have to be taken into consideration. And finally, the quality of the display and/or printing device to show the ray traced results. In an attempt to create an open workflow and interchangeable files companies have promoted the idea of an open materials library and a standard file format. Progress has been made in that effort, but there are certain proprietary looks, that represent important product differentiation that companies will never share.
Jon Peddie

Chapter 6. Applications of Ray Tracing

Abstract
Ray tracing has been traditionally used with applications for media and entertainment (3D animation, rendering), product development (CAD/CAM/CAE), life sciences (medical, molecular), energy, and other operations. The ray-tracing programs are used by engineers and artist proposing a project concept or new product design, by designers who bring the first renditions of the project or product for evaluation, by manufacturing people who build and test the project, or product virtually in the computer. And then when everything is proven and acceptable, marketing people use ray tracing to create images to sell the product. Ray tracing is used in all four stages from project concept to fulfillment. The concept of virtual prototyping and in the film industry pre-viz has been embraced by most industries and has saved millions of dollars by eliminating redos and expensive after-sales repairs.
Jon Peddie

Chapter 7. Ray-Tracing Hardware

Abstract
Ray tracing and its associative techniques are mathematical functions and as such can be executed on any computational device. The question is how long is one willing to wait for the results? General-purpose processors, CPUs, with their large addressable memory space do an excellent job at ray tracing and are still the primary engine for ray tracing. Graphics processor units, GPUs, have been used, but the basic architecture of GPU isn’t particularly well-suited for ray tracing, and GPUs have limited memory space. A new generation of specialized GPUs with specific ray-tracing features has been introduced and except for the memory space represents a real challenge to CPUs. Specialized, custom, application-specific integrated circuits (ASICs) have also been developed in an attempt to speed up the rendering time. None of them have had long-term success, and most have died still-born.
Jon Peddie

Chapter 8. Ray-Tracing Programs and Plug-ins

Abstract
There are 70 or so ray-tracing programs available, plus ray-tracing capabilities in many major CAD, 3D modeling, and content creation programs. The idea of creating a photorealistic, physically accurate synthetic image is so compelling and exciting; literally, hundreds of people have tried to do over the past 60 years. It takes such specialized skill and such an extensive material library that no single program can satisfy all the needs of all applications or stages of a project. It is not uncommon for a film or design studio to employ two to five different ray-tracing programs on one project. That reveals how vast the requirements are and why there are so many programs. And many of the programs are free, so there is no economic barrier to using ray tracing.
Jon Peddie

Backmatter

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