Book Image

Mastering openFrameworks: Creative Coding Demystified

By : Denis Perevalov
Book Image

Mastering openFrameworks: Creative Coding Demystified

By: Denis Perevalov

Overview of this book

openFrameworks is a powerful programming toolkit and library designed to assist the creative process through simplicity and intuitiveness. It's a very handy software library written in C++ to reduce the software development process, helping you to kick-start creative coding. With the help of C++ and shaders support, openFrameworks allows for the processing of all kinds of media information with your custom-developed algorithms at the lowest possible level, with the fastest speed. "Mastering openFrameworks: Creative Coding Demystified" will introduce you to a world of creative coding projects, including interactive installations, audio-visual, and sound art projects. You will learn how to make your own projects using openFrameworks. This book focuses on low-level data processing, which allows you to create really unique and cutting-edge installations and projects. "Mastering openFrameworks: Creative Coding Demystified" provides a complete introduction to openFrameworks, including installation, core capabilities, and addons. Advanced topics like shaders, computer vision, and depth cameras are also covered. We start off by discussing the basic topics such as image and video loading, rendering and processing, playing sound samples, and synthesizing new sounds. We then move on to cover 3D graphics, computer vision, and depth cameras. You will also learn a number of advanced topics such as video mapping, interactive floors and walls, video morphing, networking, and using geometry shaders. You will learn everything you need to know in order to create your own projects; create projects of all levels, ranging from simple creative-code experiments, to big interactive systems consisting of a number of computers, depth cameras, and projectors.
Table of Contents (22 chapters)
Mastering openFrameworks: Creative Coding Demystified
About the Author
About the Reviewers

Creating and modifying images

In the preceding sections, we considered different ways of drawing images loaded from files. In this section, we see how to generate new images or alter an existing image by specifying its pixels directly.

A raster image is represented as an array of pixels in memory. If we have an image with width w pixels and height h pixels, it is represented by N = w * h pixels. Normally, the horizontal rows of an image lie sequentially in memory: the w pixels of the first row, then the second row, and so on to the h row.

The pixels of the image can hold differing amounts of information depending on the image type. In openFrameworks, the following types are used:

  • The OF_IMAGE_COLOR_ALPHA type denotes a colored image with transparency. Here, each pixel is represented by 4 bytes, holding red, green, blue, and alpha color components respectively, with values from 0 to 255.

  • The OF_IMAGE_COLOR type denotes colored image without transparency. Here each pixels is represented by 3...