Table Of ContentTable of Contents
Introduction
Preface
Downloading and Compiling Demo Source Code
Basics
"Hello Triangle" - OpenGL 4 Up and Running
Extended Initialisation
OpenGL 4 Shaders
Vertex Buffer Objects
Transformation
Vectors and Matrices
Virtual Camera
Quaternion Quick-Start
Ray-Based Picking
Lighting and Texture Maps
Phong Lighting
Texture Maps
Tips and Tricks
Screen Capture
Video Capture
Debugging Shaders
Gamma Correction
Extension Checks and the Debug Callback
Uniform Buffer Objects and Mapping Buffers
Mesh Files
Importing a Mesh File
More Advanced Lighting and Texture Effects
MultiTexturing
Using Textures for Lighting Coefficients
Fragment Rejection
Alpha Blending for Transparency
Spotlights and Directional Lights
Distance Fog
Normal Mapping
Cube Maps: Sky Boxes and Environment Mapping
New Shader Stages
Geometry Shaders
Tessellation Shaders
2d Rendering
2d GUI Panels
Sprite Sheets and 2d Animation
Bitmap Fonts
Making a Font Atlas Generator Tool
Animation
Particle Systems
Hardware Skinning Part 1: Bones
Hardware Skinning Part 2: Skeleton Hierarchies
Hardware Skinning Part 3: Key-Frame Animation
Multi-Pass Rendering
Switching Framebuffer
Image Processing with a Kernel
Colour-Based Picking
Deferred Shading
Texture Projection Shadows
Discussion
Building Larger Programmes
Closing Remarks, Future Techniques, and Further Reading
Anton's OpenGL 4 Tutorials
Preface
The Point of This Book
This book is a practical guide to starting 3d programming with OpenGL, using
the most recent version. I started building this material as lab worksheets for the
practical part of Stefan Petersson's most excellent 3d Programming course at
Blekinge Tekniska Högskola in Sweden, and continued it as an on-line series
afterwards. It's now extended into a book format, for off-line viewing, and with
additional material. It would suit anyone learning 3d
programming that needs a practical guide with some help for common problems.
The original material is often used in this way by university courses and
hobbyists.
This book is a collection of worked-through examples of common real-time
rendering techniques as used in video games or student projects. There are also
some chapters or short articles for Tips and Tricks - not-so-obvious techniques
that can add a lot of value to projects or make it easier to find problems.
This is not a guide for graphics experts, nor is it intended to describe in detail the
latest features of OpenGL. It is also not intended to be an instruction to 3d
programming theory. A light introduction is given to the topics covered, but
there are much more comprehensive and capable sources for that. The idea is to
be something like a lab manual - to get you going and over the trickier and more
confusing hurdles presented by the API.
In computer lab support for graphics courses I had a couple of key jobs that I
found I was repeating over and over for students, and these are my
main motivations in the style of writing for this material:
1. To explain convoluted problems in a clear, practical, rational way, that
appeals to common sense - not to programming or mathematical
experience, and without using a lot of jargon.
2. "I only get a black screen!" - To provide a rational, step-by-step process of
elimination to debug and diagnose 3d programming problems so that they
don't look so utterly hopeless.
3. And to make a list of the most common problems. I originally started my
lab worksheets because I found that I was answering the same questions
hundreds of times!
After the first hundred or so hours of that I was able to spot a problem from the
other side of the lab, and the students would think I had some sort of super-
power. In reality it's just that the same mistakes pop up all the time for people
learning. I feel like this is the kind of help that's missing from other OpenGL
references - and it is so easy to make mistakes with the OpenGL
interface - so I've put all the advice that I can here for your benefit too.
An additional motivation for writing this content was the state of existing
reference texts. When I first started teaching there were no OpenGL 4 books
published. The larger tomes were not yet updated. At the time of writing some of
the
major texts have updated to OpenGL 4. You can assemble a collection of texts to
educate yourself, which I will list, but these are very large, and very expensive
volumes. None of them are satisfactory as a sole reference for a university
course, which means you'll need to refer to several of them.
This is an absolutely ridiculous expectation for a student budget, and I think very
disappointing for education in this area, which has so much potential to grab
attention and to motivate. I try to fill this gap here with something easy to get
into, with human-digestible instruction steps, and not expensive or too heavy to
travel with. It's still worth getting access to a
collection of the larger volumes, which will give you precise technical detail and
more advanced technical information. Perhaps you can get your library to buy
them, or pool together with other enthusiasts.
What Should I Know Before Starting?
Programming Knowledge
Graphics programming is not easy. You will need to have strong C programming
skills. You don't need to know C++ for OpenGL. The articles in this book
assume that you are familiar with the following concepts:
Built-in data-types; , , , etc. and what sort of numbers that
int float unsigned int
they can represent
Boolean logic
Functions and parameters
Arrays, loops, and strings
Compiling and linking C programmes
File reading and writing
Linking external libraries
Pointers, addresses
Casting between data types
Dynamic memory allocation and deallocation
Identifying different types of errors, and debugging
In other words, about the equivalent of the first 2 courses in a university
Computer Science programme. If you're not a C programmer, but have some
other programming background then I can suggest Herbert Schildt's "C/C++
Programmer's Reference". It has an excellent break-down of the basic
functionality of C and C++. The pocket edition is great. The official "The C
Programming Language" by Brian Kerninghan and Dennis Ritchie is in a 101
tutorial format, but it's short, boring, and expensive, although is the definitive
guide. One to borrow, perhaps!
It's possible to learn the entirety of C in a short time and keep it all in your
working knowledge. This is absolutely not the case with C++. I suggest learning
C first.
I write my code in C, but occasionally use a feature from C++, where I feel it
will save me some time. This means that I use a C++ compiler. You can quite
easily replace my C++ bits with the equivalent C code and use a C compiler.
Mathematical Knowledge
I feel that people over-emphasise mathematics as a pre-requisite for
programming. You barely need any maths to be a good programmer - what you
need is logic. We do use some very specific mathematical concepts for 3d
graphics, but actually learning mathematical concepts when you need to use
them is quite possible, and in fact, probably the most effective way to learn.
Some concepts that you might want to brush up on before starting:
Basic trigonometric functions; sine, cosine, tangent.
3d vectors. Dot and cross product functions for vectors
Matrices for affine transformations of vectors
We will be using a lot of the above techniques, and you will probably find it
useful to put together a little summary sheet of the techniques that you need a
reference for. You can get my cheat sheet at
http://antongerdelan.net/teaching/3dprog1/maths_cheat_sheet.pdf
.
Hardware
You're going to need a fairly modern graphics adapter to code in modern
OpenGL. Find out what graphics device your computer
has, and look up on Wikipedia if it will support OpenGL 3 or 4.
Description:This book is a practical guide to starting 3d programming with OpenGL, using the most recent version. It would suit anyone learning 3d programming that needs a practical guide with some help for common problems. The material is often used in this way by university courses and hobbyists. This book is
