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OpenGL Shading Language 2nd Edition
Martin Ecker writes "The Orange Book is back in its second edition. Randi J. Rost's "OpenGL Shading Language" (also called the Orange Book because of its orange cover) published by Addison-Wesley returns with 4 new chapters, roughly 140 new pages and quite a few new sample shaders. Like the first edition, the second edition of the book is one of the best introductions to GLSL - the OpenGL Shading Language - that also explains in-depth how to develop shaders in GLSL for lighting, shadows, animation, and other topics. The book targets an audience that is already familiar with computer graphics and with OpenGL. Knowledge of the C programming language is also advantageous for the reader. Since I've reviewed the first edition previously, I will focus on the new chapters of the book in this review." Read the rest of Martin's review.
OpenGL Shading Language (Second Edition)
author
Randi J. Rost
pages
740
publisher
Addison-Wesley Publishing
rating
9/10
reviewer
Martin Ecker
ISBN
0-321-33489-2
summary
A solid introduction to developing shaders in the OpenGL Shading Language GLSL.
GLSL is now officially a part of OpenGL 2.0, whereas it was only an extension to core OpenGL at the time of release of the book's first edition. Naturally, the Orange Book has been updated to reflect all the changes. Not much has changed in the shading language itself, though. However, there were some minor modifications to the C shader API used to create and upload shaders to the graphics hardware from the program running on the CPU. In order to make the transition easier for old-timers like me who have worked with the old API, the book contains an appendix that details all the changes that the shader API has undergone with the promotion to core OpenGL.
The most notable additions to the book in its second edition are the new chapters on lighting, shadows, surface characteristics, and RealWorldz, a demo that uses shaders exclusively for all rendering and that generates even the rendered models purely procedurally via shaders.
The new chapter on lighting goes into the details of developing lighting shaders that differ from traditional fixed-function lighting offered by the OpenGL fixed-function pipeline. In particular, shaders for hemi-sphere lighting, image-based lighting using environment maps as light probes, and spherical harmonics lighting are developed in this chapter. Note that the theory behind spherical harmonics lighting is not presented in the book. So if you want to fully understand the presented shaders, you will have to read up on the theory in the references given in the book. The chapter on lighting is concluded by a discussion of the ÜberLight shader, a shader for a very versatile lighting model initially presented as RenderMan shader by Pixar Animation Studios.
An important topic in computer graphics now has its own chapter in the Orange Book: Shadows. The new chapter on shadows presents ambient occlusion, shadow maps, and an interesting technique for rendering shadow volumes using deferred shading. The latter technique can be used to render soft shadows convincingly.
Another new chapter in the second edition of the book is on surface characteristics. This chapter discusses and develops shaders to render surface materials that exhibit complex light interaction. The chapter starts out with a discussion of refraction and presents shaders to archive the classic Fresnel reflection/refraction and chromatic aberration effects. Then diffraction, i.e. light bending around sharp edges, is discussed and a shader is developed that renders a vinyl record realistically. Finally, the chapter focuses on BRDF-based lighting and develops various material shaders using the BRDF model.
The final new chapter in the second edition is on RealWorldz. RealWorldz is a demo that renders planets with fractal terrain, oceans, sky, and other effects. Everything in the demo is generated procedurally through GLSL shaders and the chapter describes the techniques used in implementing the demo. At the end of the chapter it says that the demo is available upon request from 3Dlabs, which I find ab it disappointing. Let's hope that the authors put up a downloadable version of the demo, or at least a video of the demo, on the book's webpage.
As in the previous edition, all images and diagrams in the book are in black and white, except for a few pages that contain 38 color plates in the middle of the book. In addition to the images from the first edition, the book now has some very impressive images from the RealWorldz demo. A nice addition to the book is the detachable cheat sheet at the end of the book, which contains a quick reference of GLSL and the shader API entry points - very handy to have on your desk in the heat of a late-night coding session.
The book's accompanying website at http://www.3dshaders.com/ offers the source code to all the shaders presented in the book for download. Also available are other shaders not mentioned in the book and a demo application including source code, which nicely demonstrates the shaders in action. The demo application and most of the shaders are available under a very liberal BSD-style open source license.
The book "OpenGL Shading Language (Second Edition)" remains an excellent introduction to shader programming with GLSL. It provides a profound discussion of the shading language itself as well as the C shader API used to create and manage shaders in the host program. The book also has numerous chapters on developing shaders for various applications, such as lighting, shadows, animation, and other areas of real-time computer graphics. The newly added chapters in the second edition nicely complement an already good book. If you're interested in learning GLSL and shader programming in OpenGL, this is the book to get.
About the review author:
The author has been involved in real-time graphics programming for more than 10 years and works as a games developer for arcade games. In his rare spare time he works on a graphics-related open source project called XEngine http://xengine.sourceforge.net./"
You can purchase OpenGL Shading Language from bn.com. Slashdot welcomes readers' book reviews -- to see your own review here, read the book review guidelines, then visit the submission page.
GLSL is now officially a part of OpenGL 2.0, whereas it was only an extension to core OpenGL at the time of release of the book's first edition. Naturally, the Orange Book has been updated to reflect all the changes. Not much has changed in the shading language itself, though. However, there were some minor modifications to the C shader API used to create and upload shaders to the graphics hardware from the program running on the CPU. In order to make the transition easier for old-timers like me who have worked with the old API, the book contains an appendix that details all the changes that the shader API has undergone with the promotion to core OpenGL.
The most notable additions to the book in its second edition are the new chapters on lighting, shadows, surface characteristics, and RealWorldz, a demo that uses shaders exclusively for all rendering and that generates even the rendered models purely procedurally via shaders.
The new chapter on lighting goes into the details of developing lighting shaders that differ from traditional fixed-function lighting offered by the OpenGL fixed-function pipeline. In particular, shaders for hemi-sphere lighting, image-based lighting using environment maps as light probes, and spherical harmonics lighting are developed in this chapter. Note that the theory behind spherical harmonics lighting is not presented in the book. So if you want to fully understand the presented shaders, you will have to read up on the theory in the references given in the book. The chapter on lighting is concluded by a discussion of the ÜberLight shader, a shader for a very versatile lighting model initially presented as RenderMan shader by Pixar Animation Studios.
An important topic in computer graphics now has its own chapter in the Orange Book: Shadows. The new chapter on shadows presents ambient occlusion, shadow maps, and an interesting technique for rendering shadow volumes using deferred shading. The latter technique can be used to render soft shadows convincingly.
Another new chapter in the second edition of the book is on surface characteristics. This chapter discusses and develops shaders to render surface materials that exhibit complex light interaction. The chapter starts out with a discussion of refraction and presents shaders to archive the classic Fresnel reflection/refraction and chromatic aberration effects. Then diffraction, i.e. light bending around sharp edges, is discussed and a shader is developed that renders a vinyl record realistically. Finally, the chapter focuses on BRDF-based lighting and develops various material shaders using the BRDF model.
The final new chapter in the second edition is on RealWorldz. RealWorldz is a demo that renders planets with fractal terrain, oceans, sky, and other effects. Everything in the demo is generated procedurally through GLSL shaders and the chapter describes the techniques used in implementing the demo. At the end of the chapter it says that the demo is available upon request from 3Dlabs, which I find ab it disappointing. Let's hope that the authors put up a downloadable version of the demo, or at least a video of the demo, on the book's webpage.
As in the previous edition, all images and diagrams in the book are in black and white, except for a few pages that contain 38 color plates in the middle of the book. In addition to the images from the first edition, the book now has some very impressive images from the RealWorldz demo. A nice addition to the book is the detachable cheat sheet at the end of the book, which contains a quick reference of GLSL and the shader API entry points - very handy to have on your desk in the heat of a late-night coding session.
The book's accompanying website at http://www.3dshaders.com/ offers the source code to all the shaders presented in the book for download. Also available are other shaders not mentioned in the book and a demo application including source code, which nicely demonstrates the shaders in action. The demo application and most of the shaders are available under a very liberal BSD-style open source license.
The book "OpenGL Shading Language (Second Edition)" remains an excellent introduction to shader programming with GLSL. It provides a profound discussion of the shading language itself as well as the C shader API used to create and manage shaders in the host program. The book also has numerous chapters on developing shaders for various applications, such as lighting, shadows, animation, and other areas of real-time computer graphics. The newly added chapters in the second edition nicely complement an already good book. If you're interested in learning GLSL and shader programming in OpenGL, this is the book to get.
About the review author:
The author has been involved in real-time graphics programming for more than 10 years and works as a games developer for arcade games. In his rare spare time he works on a graphics-related open source project called XEngine http://xengine.sourceforge.net./"
You can purchase OpenGL Shading Language from bn.com. Slashdot welcomes readers' book reviews -- to see your own review here, read the book review guidelines, then visit the submission page.
I still don't understand why the compiler was moved into the GL server. I mean, it makes writing ICDs even harder than it is already, and doesn't have any obvious benefits. Why not simply standardize some bytecodes and have people write free GLSL->bytecode compilers?
This sig does not contain any SCO code.
Since the Playstation 3 is using OpenGL, could the information in this book be relevant for people writing games for the PS3? Or are shaders in the RSX different?
AFAIK it is a driver issue, actually. If MS wanted to kill off OpenGL, they would simply dump it. However, since writing an OpenGL ICD is far from being an easy task, the d3d-gl-bridge serves as a default 1.4 GL implementation. This is useful for cheap graphics chips which have drivers lacking good GL support (my old laptops Lynx3DM chip for example). IHVs still have the option to provide their own ICD simply by replacing the OpenGL32.dll. Since D3D and OGL are just interfaces to the driver, it is possible for them to mix the two, for example by providing an overall graphics server (which acts like a GL server too) and D3D/OGL apps being clients.
This sig does not contain any SCO code.
This is pretty common among standardized technologies. Must I remind you of the CDROM drive?
Yellow Book (Format)
Red Book (Audio)
Green Book (Multimedia)
Orange Book (RO/RW)
White Book (VCD)
Blue Book (Graphics)
Beige Book (Photo)
Purple Book (Double Density)
Scarlet Book (Super Audio?)
That's why it's so important to add which technology you're talking about. e.g. "Orange Book Security", "Orange Book CD Rewritables", and "OpenGL Orange Book".
Javascript + Nintendo DSi = DSiCade
The current nVidia drivers do not contain OpenGL support - instead, you get the Microsoft wrapper. However, this very well could be a case of nVidia just giving you the bare minimum to mess around with the beta. So there is still hope..
The "Red Book" is the official book on OpenGL itself, and it's red.
I thought the "Little Red Book" was the official book on the GPL. Oh bother, I get so confused.
I do what the voices on my console tell me to do.
I think we should go one further -- I really miss the times on the Control Data mainframe, with its 6-bit character codes, so (at least in the "scientific" character set) you didn't have to deal with that mamby-pamby lower-case text either. Hollerith cards and fan-fold printouts -- now that's programming!
To really upgrade your graphics experience, replace your ASR-33 with a DECWriter LA-20 and watch those frame rates soar!
The universe is a figment of its own imagination.
Not sure if this post was supposed to be in jest (not modded as funny, so maybe not..), but the OGL Programming guide is called the "Red book" and the Reference is called the "blue book" (because of their respective covers) and have been for years. It only made sense when they added shaders to OGL to refer to the book in the same way.
I am the maverick of Slashdot
Sigh.....
It really hurts my language designer nerve when I see the state of shading languages. They are all supposedly based on C, which is total nonsense. Only the syntax looks like C, the semantics is much more like Ada than anything else. And then there is the question of whether C or Ada are the most suitable language to mimic in this situation. I think not. Shading computations are inherently functional. Any shader is easily and succinctly specified as a mathematical formula. I think that should be reflected in the shading language as well. Design the language so that it is suitable for its application! It is a truism that functional languages are much better suited in modelling these kinds of mathematical equations that C or Ada (although C and Ada both have their merits as well in other areas).
</rant>
OK. Well I just needed to get that off my chest. I feel much better already.
Graphics programmers are more likely to be familiar with procedural programming than functional programming because they need to have a lot of control over how the code executes. C is probably the most widely known programming language. New procedural languages are often described as having a C-like syntax to make it sound less intimidating, even if it's actually more similar to another language.
If you can read this sig, you're too close.
The controversy is that for IHVs to provide their own ICD requires internal knowledge of the Desktop Compositing system that Microsoft has apparently not provided to the level needed for proper support. Microsoft is taking full steps to eliminate OpenGL in Windows Vista, starting with pushing it aside as a second-class citizen. The goal is to put their Windows/DirectX APIs everywhere, which was the whole purpose of the X-Box to begin with (in other words, they don't give two shits about games; they just want to extend the Windows monopoly after seeing the rising success of the console market, and game quality be damned...so we get XBox360 commercials espousing the wonders of sweat on a basketball player instead of good gameplay).
"Sufferin' succotash."
And when the guy with the BFG comes sneeking up, you get a garbage collection. No thanks
Inventions have long since reached their limit, and I see no hope for further development.-- Frontinus, 1st cent. AD
Yes, I know. Your point is entirely valid. I just wish there weren't so much inertia in the field of programming languages. Programmers could start learning languages with a syntax different from C and with a funkier (more powerful) semantics. It will make them better programmers. But I guess I just have to keep on dreaming about this.
There is nothing that says that a functional language needs to have automatic memory management (such as garbage collection). The kind of language design I have in mind would not.
While this is a nice tour-de-force demo of a capability, it strikes me that a more important demo of this scale is to use ALL of OpenGL's capabilities to its fullest, and highlight "best practices" for presenting highly capable scene graphs with a lot of really nice and popular shading effects.
Just showing that you can implement PAC-MAN using Excel macros does not particularly give the reader a good understanding of making the fastest-possible PAC-MAN game, nor the most robust actuarial financial model.
[
Keep in mind that OpenGL does not itself directly support scene graphs.
The modelview matrix stack can easily be used to implement scene graphs,
but OpenGL defines no data structure for actually representing a scene graph.
I'm just nitpicking though. Your point is a good one: just because you can code an entire application as a bunch of shaders, doesn't mean it makes sense to.
Hamsters are at least as feathery as penguins. HamLix
So write a compiler from functional-language-of-choice to GLSL (or Cg or HLSL or...) and be done with it.
It's not *that* hard...
Thats a really cool idea.
I wonder what the ideal semantics for such a language would be.
Maybe like Mathimetica or Matlab?
Cheers,
Ben
Re-using these names is nothing new.
LRC, the best-read libertarian site on the web
Sorry, but ALL of you in this thread are wrong. The REAL Orange Book is FDA's list of approved drugs. Even Google agrees.
Only turn on the GC when the inventory screen is up or during a cut scene.
TWW
"Encyclopedia" is to "Wikipedia" what "Library" is to "Some people at a bus stop"
And when the guy with the BFG comes sneeking up, you get a garbage collection
There is no dynamic memory allocation in shaders.
Dear Mods,
I'm sorry that my "flaimbait" was not able to attract more (read: any) flames. Perhaps you will choose a different brand of "flaimbait" on your next phishing trip.
Regards,
WTF