Book Image

OpenGL ES 3.0 Cookbook

By : Parminder Singh
Book Image

OpenGL ES 3.0 Cookbook

By: Parminder Singh

Overview of this book

<p>"Write once, use anywhere" is truly the power behind OpenGL ES and has made it an embedded industry standard. The library provides cutting-edge, easy-to-use features to build a wide range of applications in the gaming, simulation, augmented-reality, image-processing, and geospatial domains.</p> <p>The book starts by providing you with all the necessary OpenGL ES 3.0 setup guidelines on iOS and Android platforms. You'll go on to master the fundamentals of modern 3D graphics, such as drawing APIs, transformations, buffer objects, the model-view-project analogy, and much more. The book goes on to deal with advanced topics and offers a wide range of recipes on the light shading, real-time rendering techniques with static and procedure textures to create stunning visualizations and runtime effects.</p>

Related Content you might be interested in

Current Title:

Small book image
OpenGL ES 3.0 Cookbook
Parminder Singh
May, 2015 | 514 pages
No titles found
Table of Contents (21 chapters)
OpenGL ES 3.0 Cookbook
OpenGL ES 3.0 Cookbook
Credits
Credits
About the Author
About the Author
Acknowledgments
Acknowledgments
About the Reviewers
About the Reviewers
www.PacktPub.com
www.PacktPub.com
Preface
Preface
Free Chapter
1
OpenGL ES 3.0 on Android/iOS
OpenGL ES 3.0 on Android/iOS
Introduction
Programming shaders in OpenGL ES shading language 3.0
Loading and compiling a shader program
Linking a shader program
Checking errors in OpenGL ES 3.0
Using the per-vertex attribute to send data to a shader
Using uniform variables to send data to a shader
Programming OpenGL ES 3.0 Hello World Triangle
Using JNI on Android to communicate with C/C++
Developing an Android OpenGL ES 3.0 application
Developing an iOS OpenGL ES 3.0 application
2
OpenGL ES 3.0 Essentials
OpenGL ES 3.0 Essentials
Introduction
Building prototypes using the GLPI framework
Implementing touch events
Rendering primitives with vertex arrays
Drawing APIs in OpenGL ES 3.0
Efficient rendering with Vertex Buffer Object
Transformations with the model, view, and projection analogies
Understanding the projection system in GLPI
Culling in OpenGL ES 3.0
Depth testing in OpenGL ES 3.0
3
New Features of OpenGL ES 3.0
New Features of OpenGL ES 3.0
Introduction
Managing variable attributes with qualifiers
Grouping uniforms and creating buffer objects
Managing VBO with Vertex Array Objects
Reading and writing buffer objects with mapping
Render multiple objects with geometry instancing
Rendering multiple primitives with primitive restart
4
Working with Meshes
Working with Meshes
Introduction
Creating polygon meshes with Blender
Rendering the wavefront OBJ mesh model
Rendering the 3Ds mesh model
5
Light and Materials
Light and Materials
Introduction
Implementing the per-vertex ambient light component
Implementing the per-vertex diffuse light component
Implementing the per-vertex specular light component
Optimizing the specular light with the halfway vector
Gouraud shading – the per-vertex shading technique
Phong shading – the per-fragment shading technique
Implementing directional and point light
Implementing multiple lights in a scene
Implementing two-side shading
6
Working with Shaders
Working with Shaders
Introduction
Implementing the wobble and ripple effect
Procedural texture shading with object coordinates
Creating the circular pattern and making them revolve
Generating the brick pattern
Generating the polka dot pattern
Discarding fragments
Procedural texture shading with texture coordinates
7
Textures and Mapping Techniques
Textures and Mapping Techniques
Introduction
Applying texture with UV mapping
Efficient rendering with the ETC2 compressed texture
Applying multiple textures
Implementing Skybox with seamless cube mapping
Implementing reflection and refraction with environment mapping
Implementing render to texture with Frame Buffer Objects
Implementing terrain with displacement mapping
Implementing bump mapping
8
Font Rendering
Font Rendering
Introduction
Font rendering with the FreeType project
Rendering different languages with Harfbuzz
Rendering text on Head Up Display
9
Postscreen Processing and Image Effects
Postscreen Processing and Image Effects
Introduction
Detecting scene edges with the Sobel operator
Making the scene blur with the Gaussian blur equation
Making a scene glow real time with the bloom effect
Painting the scene like a cartoon shading
Generating an embossed scene
Implementing grayscale and CMYK conversions
Implementing fisheye with barrel distortion
Implementing the binocular view with procedural texturing
Twirling the image
Sphere illusion with textured quadrilateral
10
Scene Management with Scene Graphs
Scene Management with Scene Graphs
Introduction
Implementing the first scene using a scene graph
Adding local and relative transformations
Adding parent-child support in the scene graph
Creating complex models with a transformation graph
Implementing picking with the ray trace technique
Implementing 2D textured button widgets
Navigating the scene with a camera system
Implementing the scene with multiple views
11
Anti-aliasing Techniques
Anti-aliasing Techniques
Introduction
Understanding the sampling rate technique
Understanding the post processing technique
Implementing fast approximate anti-aliasing
Implementing adaptive anti-aliasing
Implementing an anti-aliased circle geometry
12
Real-time Shadows and Particle System
Real-time Shadows and Particle System
Introduction
Creating shadows with shadow mapping
Softening the shadow edges using PCF
Using variance shadow mapping
Simulating the particle system
Transform feedback particle system with sync objects and fences
Supplementary Information on OpenGL ES 3.0
Supplementary Information on OpenGL ES 3.0
The fixed function and programmable pipeline architecture
Software requirements for OpenGL ES 3.0 – Android ADT
Developing the Hello World Triangle application on Android Studio with OpenGL ES 3.0
Software requirements for OpenGL ES 3.0 – iOS
Opening a sample project on Android ADT and iOS
Application of the Lambert's cosine law
Calculating cosine between two vectors
Swizzling
Index
Index

Culling in OpenGL ES 3.0

Culling is an important technique in 3D graphics. It is used to discard the faces that are not visible to the user. In an enclosed geometry, the faces pointing towards the camera hide the faces behind it, either partially or completely. These faces can be easily avoided during rendering by the culling technique. This is an easier way to speed up the performance in OpenGL ES graphics. There are two types of faces:

  • Front face: The face in an enclosed 3D object that points outward are considered to be the front face

  • Back face: The face in an enclosed 3D object that points inside of these faces are considered as to be the back face

How to do it...

Culling can be enabled in OpenGL ES 3.0 using the glenable API with GL_CULL_FACE as state flag. By default, OpenGL ES 3.0 culls the back face. This can be changed using the glCullFace API. Tap on the screen to switch between the front and back culling modes. This recipe will display the outside faces of the cube when back face...

Previous Section
End of Section 10
Next Section