Processing – Page 9 – Jeff Thompson

UPDATE: these functions have been updated and moved to GitHub

Released today, version 0.9 of my 2d collision detection functions for Processing!

While some tools already exist, like the excellent Box2D, the source code is not easy to understand and the implementation is a bit complex. Other examples (equally great), like the line-line collision in the toxiclibs collection, use vector math which isn’t great for us “creative programmers” (ie: those like me who got bad grades in high school math).

Instead, these tools can be used as simple, one-line commands to determine whether two objects have collided. Designed for simple games and interactive systems, they are intended to be building blocks for larger projects.

Functions include:

Point/Point
Point/Rect
Point/Ball
Rect/Rect
Ball/Ball
Ball/Rect
Point/Line
Line/Line
Ball/Line

Download here via Google Project Hosting

I keep finding myself needing to be able to run Unix commands within Processing sketches (maybe too much time spent writing Bash scripts lately), but no one seems to have a good solution. Today I was able to get the Java exec() command to work within Processing… hooray!

EDIT: want to do something more complex? You can run a Bash script too!

/*
 * RUN UNIX COMMANDS IN PROCESSING
 * Jeff Thompson
 * Adapted and annotated from code by Wharfie
 * http://www.computing.net/answers/unix/run-unix-command-thr-java-program-/5887.html
 * July 2011
 *
 * Runs Unix commands from within Processing.  This can be *super* helpful for
 * doing complex operations on folders such as copying or compressing multiple
 * files.  A simple command can make quick work of what would otherwise be a
 * cumbersome task in Processing and will likely be much quicker than any Java
 * implementation of the same process.
 *
 * You will likely need to specify the full path where you want to work, unless your
 * location is relative to your sketch.  For example: /Users/jeffthompson/Desktop
 *
 * Suggestions to try:
 *   whoami                            prints username currently logged on
 *   ls                                this lists all files in the particular location
 *   wc -w filename.extension          this counts words in a particular file
 *   cp sourcefile.ext destfile.txt    makes a copy of a file to a new one
 *   ./yourBashScript.sh               run a Bash script
 *
 * For more ideas, look at the excellent SS64 site: http://ss64.com/bash
 *
 * www.jeffreythompson.org
 */

void setup() {

  // what command to run
  String commandToRun = "whoami";
  // String commandToRun = "ls";
  // String commandToRun = "wc -w sourcefile.extension";
  // String commandToRun = "cp sourcefile.extension destinationfile.extension";
  // String commandToRun = "./yourBashScript.sh"

  File workingDir = new File(sketchPath(""));                  // where to do it - should be full path
  String returnedValues;                                       // value to return any results

  // give us some info:
  println("Running command: " + commandToRun);
  println("Location:        " + workingDir);
  println("---------------------------------------------\n");

  // run the command!
  try {

    // complicated!  basically, we have to load the exec command within Java's Runtime
    // exec asks for 1. command to run, 2. null which essentially tells Processing to
    // inherit the environment settings from the current setup (I am a bit confused on
    // this so it seems best to leave it), and 3. location to work (full path is best)
    Process p = Runtime.getRuntime().exec(commandToRun, null, workingDir);

    // variable to check if we've received confirmation of the command
    int i = p.waitFor();

    // if we have an output, print to screen
    if (i == 0) {

      // BufferedReader used to get values back from the command
      BufferedReader stdInput = new BufferedReader(new InputStreamReader(p.getInputStream()));

      // read the output from the command
      while ( (returnedValues = stdInput.readLine ()) != null) {
        println(returnedValues);
      }
    }

    // if there are any error messages but we can still get an output, they print here
    else {
      BufferedReader stdErr = new BufferedReader(new InputStreamReader(p.getErrorStream()));

      // if something is returned (ie: not null) print the result
      while ( (returnedValues = stdErr.readLine ()) != null) {
        println(returnedValues);
      }
    }
  }

  // if there is an error, let us know
  catch (Exception e) {
    println("Error running command!");
    println(e);
  }

  // when done running command, quit
  println("\n---------------------------------------------");
  println("DONE!");
  exit();
}

* RUN UNIX COMMANDS IN PROCESSING

* Jeff Thompson

* Adapted and annotated from code by Wharfie

* http://www.computing.net/answers/unix/run-unix-command-thr-java-program-/5887.html

* July 2011

* Runs Unix commands from within Processing. This can be *super* helpful for

* doing complex operations on folders such as copying or compressing multiple

* files. A simple command can make quick work of what would otherwise be a

* cumbersome task in Processing and will likely be much quicker than any Java

* implementation of the same process.

* You will likely need to specify the full path where you want to work, unless your

* location is relative to your sketch. For example: /Users/jeffthompson/Desktop

* Suggestions to try:

* whoami prints username currently logged on

* ls this lists all files in the particular location

* wc -w filename.extension this counts words in a particular file

* cp sourcefile.ext destfile.txt makes a copy of a file to a new one

* ./yourBashScript.sh run a Bash script

* For more ideas, look at the excellent SS64 site: http://ss64.com/bash

* www.jeffreythompson.org

void setup() {

// what command to run

String commandToRun = "whoami";

// String commandToRun = "ls";

// String commandToRun = "wc -w sourcefile.extension";

// String commandToRun = "cp sourcefile.extension destinationfile.extension";

// String commandToRun = "./yourBashScript.sh"

File workingDir = new File(sketchPath("")); // where to do it - should be full path

String returnedValues; // value to return any results

// give us some info:

println("Running command: " + commandToRun);

println("Location: " + workingDir);

println("---------------------------------------------\n");

// run the command!

try {

// complicated! basically, we have to load the exec command within Java's Runtime

// exec asks for 1. command to run, 2. null which essentially tells Processing to

// inherit the environment settings from the current setup (I am a bit confused on

// this so it seems best to leave it), and 3. location to work (full path is best)

Process p = Runtime.getRuntime().exec(commandToRun, null, workingDir);

// variable to check if we've received confirmation of the command

int i = p.waitFor();

// if we have an output, print to screen

if (i == 0) {

// BufferedReader used to get values back from the command

BufferedReader stdInput = new BufferedReader(new InputStreamReader(p.getInputStream()));

// read the output from the command

while ( (returnedValues = stdInput.readLine ()) != null) {

println(returnedValues);

}

// if there are any error messages but we can still get an output, they print here

else {

BufferedReader stdErr = new BufferedReader(new InputStreamReader(p.getErrorStream()));

// if something is returned (ie: not null) print the result

while ( (returnedValues = stdErr.readLine ()) != null) {

println(returnedValues);

}

// if there is an error, let us know

catch (Exception e) {

println("Error running command!");

println(e);

}

// when done running command, quit

println("\n---------------------------------------------");

println("DONE!");

exit();

}

Tag: Processing

Forest Fire Simulation

Collision Detection Functions for Processing Released!

Maxwell’s Demon Game

Brownian Triangles – Animation

Brownian Triangles – Zoomed In

Brownian Triangles

Ride The Lightning – Sorted

Unix Commands Within Processing

Sample-Tracing

Sample-Tracing Glitch