Book Image

OpenGL Development Cookbook

By : Muhammad Mobeen Movania
Book Image

OpenGL Development Cookbook

By: Muhammad Mobeen Movania

Overview of this book

OpenGL is the leading cross-language, multi-platform API used by masses of modern games and applications in a vast array of different sectors. Developing graphics with OpenGL lets you harness the increasing power of GPUs and really take your visuals to the next level. OpenGL Development Cookbook is your guide to graphical programming techniques to implement 3D mesh formats and skeletal animation to learn and understand OpenGL. OpenGL Development Cookbook introduces you to the modern OpenGL. Beginning with vertex-based deformations, common mesh formats, and skeletal animation with GPU skinning, and going on to demonstrate different shader stages in the graphics pipeline. OpenGL Development Cookbook focuses on providing you with practical examples on complex topics, such as variance shadow mapping, GPU-based paths, and ray tracing. By the end you will be familiar with the latest advanced GPU-based volume rendering techniques.
Table of Contents (15 chapters)
OpenGL Development Cookbook
Credits
About the Author
About the Reviewers
www.PacktPub.com
Preface
Index

Implementing volume rendering using 3D texture slicing


Volume rendering is a special class of rendering algorithms that allows us to portray fuzzy phenomena, such as smoke. There are numerous algorithms for volume rendering. To start our quest, we will focus on the simplest method called 3D texture slicing. This method approximates the volume-density function by slicing the dataset in front-to-back or back-to-front order and then blends the proxy slices using hardware-supported blending. Since it relies on the rasterization hardware, this method is very fast on the modern GPU.

The pseudo code for view-aligned 3D texture slicing is as follows:

  1. Get the current view direction vector.

  2. Calculate the min/max distance of unit cube vertices by doing a dot product of each unit cube vertex with the view direction vector.

  3. Calculate all possible intersections parameter (λ) of the plane perpendicular to the view direction with all edges of the unit cube going from the nearest to farthest vertex, using min...