Book Image

Processing 2: Creative Programming Cookbook

Book Image

Processing 2: Creative Programming Cookbook

Overview of this book

Processing is probably the best known creative coding environment that helps you bridge the gap between programming and art. It enables designers, artists, architects, students and many others to explore graphics programming and computational art in an easy way, thus helping you boost your creativity. "Processing 2: Creative Programming Cookbook" will guide you to explore and experience the open source Processing language and environment, helping you discover advanced features and exciting possibilities with this programming environment like never before. You'll learn the basics of 2D and 3D graphics programming, and then quickly move up to advanced topics such as audio and video visualization, computer vision, and much more with this comprehensive guide. Since its birth in 2001, Processing has grown a lot. What started out as a project by Ben Fry and Casey Reas has now become a widely used graphics programming language. Processing 2 has a lot of new and exciting features. This cookbook will guide you to explore the completely new and cool graphics engine and video library. Using the recipes in this cookbook, you will be able to build interactive art for desktop computers, Internet, and even Android devices! You don't even have to use a keyboard or mouse to interact with the art you make. The book's next-gen technologies will teach you how to design interactions with a webcam or a microphone! Isn't that amazing? "Processing 2: Creative Programming Cookbook" will guide you to explore the Processing language and environment using practical and useful recipes.
Table of Contents (18 chapters)
Processing 2: Creative Programming Cookbook
Credits
About the Author
About the Reviewers
www.PacktPub.com
Preface
Index

Responding to touch interaction


People have become used to interacting with a device by tapping and swiping on a touchscreen. In this recipe, we'll take a look at how you can detect when a user is touching the screen, and let your sketch respond to that interaction. We'll make a simple drawing application to see how it's done.

How to do it...

We'll start by writing the setup() function and declare a boolean variable. If the value of this variable is true, we'll draw some things on the screen.

boolean touching = false;
  
void setup()
{
  size( displayWidth, displayHeight );
  smooth();
  
  background( 0 );
}

To respond to a user touching the screen, we'll override the surfaceTouchevent() method. If we detect a touch we'll set the touching variable to true:

public boolean surfaceTouchEvent( MotionEvent event )
{
  if ( event.getAction() == 2 ) {
    touching = true;
  } else {
    touching = false;
  }
    
  return super.surfaceTouchEvent( event );
}

In the draw() function, we'll add the mouseX...