Example code from the OpenGL 4 Shading Language Cookbook, 3rd Edition

The example code from the OpenGL 4 Shading Language Cookbook, 3rd Edition, by David Wolff and published by Packt Publishing.

Requirements

To compile these examples, you'll need the following:

• The GLM Mathematics Library version 0.9.6 or later. Note that versions prior to 0.9.6 may not work properly because of a switch from degrees to radians. GLM 0.9.5 will work, but you'll need to add #define GLM_FORCE_RADIANS prior to including the glm header files.
• GLFW version 3.0 or later.

Compiling the examples

The example code builds with CMake. Note that the examples for Chapter 10 will not function on MacOS due to lack of support for compute shaders on that platform.

1. Install GLFW by following the instructions on their web site.
2. Install the latest version of GLM. Note that for CMake to find GLM correctly, you need to run the install "build" (e.g. make install) or install GLM from your favorite package manager. Otherwise, the CMake config files will not be created/available.
3. Download this example code from github, or clone using git.
4. Run cmake. If cmake has difficulties finding the GLFW or GLM installations, set the variable CMAKE_PREFIX_PATH to help cmake find them.
   It can be tricky to get CMake to find the GLM libraries, unfortunately. See below for tips.
5. Compile by running make.

Any problems, create an issue on github.

Tips for getting CMake to find GLM

When searching for GLM, CMake looks for the files glmConfig.cmake and glmConfigVersion.cmake.

If you install GLM using a package manager such as Homebrew on macOS, or a Linux package manager the cmake files should already be included.

Otherwise, if you're using the GLM source distribution, you'll have to run GLM through CMake to get it to generate the glmConfig.cmake and glmConfigVersion.cmake files. It is frustrating, I wish that the GLM maintainers didn't require this.

1. Download GLM and extract it to some location: GLM_SRC
2. cd $GLM_SRC
3. mkdir build
4. cd build
5. cmake -D GLM_TEST_ENABLE=OFF -D CMAKE_INSTALL_PREFIX=MY_GLM_LOCATION ..
6. cmake --build . --target install

Replace GLM_SRC above with the place where you extracted the GLM zip file, and replace MY_GLM_LOCATION with the location where you want to install GLM. This should generate the needed cmake files and install all of GLM to MY_GLM_LOCATION.

Tips for compiling for Windows with Visual Studio

• Use the Visual Studio target in CMake: -G "Visual Studio...", open the Visual Studio solution. You should see one project per chapter.
• Each chapter requires a command line argument to choose a recipe. When running in VS, be sure to set the 'Command Argument' under 'Properties' for the appropriate recipe.

OpenGL Function Loading

An OpenGL header file and a function loader for a 4.3 core profile are included with this project. They were generated using GLAD. This loader should also work on MacOS under a 4.1 core profile, but of course not all functions will load.

The code has been tested with OpenGL 4.3 on Windows/Linux and OpenGL 4.1 on MacOS.

OpenGL 4 Shading Language Cookbook - Third Edition

This is the code repository for OpenGL 4 Shading Language Cookbook - Third Edition, published by Packt.

Build high-quality, real-time 3D graphics with OpenGL 4.6, GLSL 4.6 and C++17

What is this book about?

OpenGL 4 Shading Language Cookbook, Third Edition provides easy-to-follow recipes that first walk you through the theory and background behind each technique, and then proceed to showcase and explain the GLSL and OpenGL code needed to implement them.

This book covers the following exciting features:

• Compile, debug, and communicate with shader programs
• Use compute shaders for physics, animation, and general computing
• Learn about features such as shader storage buffer objects and image load/store
• Utilize noise in shaders and learn how to use shaders in animations
• Use textures for various effects including cube maps for reflection or refraction

If you feel this book is for you, get your copy today!

Instructions and Navigations

All of the code is organized into folders. For example, Chapter02.

The code will look like the following:

glfwWindowHint(GLFW_CONTEXT_VERSION_MAJOR, 4);
glfwWindowHint(GLFW_CONTEXT_VERSION_MINOR, 6);
glfwWindowHint(GLFW_OPENGL_FORWARD_COMPAT, GL_TRUE);
glfwWindowHint(GLFW_OPENGL_PROFILE, GLFW_OPENGL_CORE_PROFILE);
GLFWwindow *window = glfwCreateWindow(800, 600, "Title", nullptr, nullptr);

Following is what you need for this book: If you are a graphics programmer looking to learn the GLSL shading language, this book is for you. A basic understanding of 3D graphics and programming experience with C++ are required.

With the following software and hardware list you can run all code files present in the book (Chapter 1-11).

Software and Hardware List

Chapter	Software required	OS required
All	GLM Mathematics Library	Windows, Mac OS X, and Linux (Any)
	GLFW	Windows, Mac OS X, and Linux (Any)
	CMake	Windows, Mac OS X, and Linux (Any)
	Visual Studio 2017	Windows, Mac OS X, and Linux (Any)

We also provide a PDF file that has color images of the screenshots/diagrams used in this book. Click here to download it.

Errata

• Page 238 (line 24): GLenumdrawBuffers[] = {GL_NONE, GL_COLOR_ATTACHMENT0, should be GLenum drawBuffers[] = {GL_NONE, GL_COLOR_ATTACHMENT0.
• Page 375 (last line): This recipe was inspired by a blog post by Wojciech Toman (no longer publicly available), has been removed please ignore the line
• Page 371 (Code snippet 1 ,second last line): vec3 rustColor = mix( MaterialColor.rgb, vec3(0.01), noise.a );, should be vec3 rustColor = mix( MaterialColor.rgb, vec3(0.01), noise );
• Page 328 (line 24): **When GL_NEAREST is the interpolation mode (as it is in our case) the result will be 1.0, or 0.0. **should beWhen GL_COMPARE_REF_TO_TEXTURE is the texture comparison mode (as it is in our case) the result will be either 1.0 or 0.0
• Page 327 (tip second line): because we need a 2D position and a depth , should be because we need a 2D texture coordinate and a reference depth value for the comparison
• Page 279 ( line 10): For example, to find ha, we use the interior angle at vertex C (β) , should be For example, to find ha, we use the interior angle at vertex B (β)
• Page 264 ( line 2): indicates the index within the GL_ATOMIC_COUTER_BUFFER binding point (refer, should be indicates the index within the GL_ATOMIC_COUNTER_BUFFER binding point (refer
• Page 255 ( line 4): a variety of techniques for doing this; one of the most common technique is to keep a list of should be a variety of techniques for doing this; one of the most common techniques is to keep a list of
• Page 320 ( information tip): range for the depth values (say between 0 and 100) via should be range for the depth values (say between 0 and 1) via

Related products

• Godot Engine Game Development Projects [Packt] [Amazon]

• Mastering C++ Game Development [Packt] [Amazon]

Get to Know the Author

David Wolff is a professor in the computer science department at Pacific Lutheran University (PLU). He received a PhD in Physics and an MS in computer science from Oregon State University. He has been teaching computer graphics to undergraduates at PLU for over 17 years, using OpenGL.

Other books by the author

• OpenGL 4.0 Shading Language Cookbook
• OpenGL 4.0 Shading Language Cookbook, Second Edition

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