Making Things Talk

370 MAKING THINGS TALK

Chapter 1

Hello World!

Language: Processing

Prints out “Hello World!”

println("Hello World!\n");

Triangle drawing program

Language: Processing

Draws a triangle whenever the mouse button is not

pressed. Erases when the mouse button is pressed.

// declare your variables:

float redValue = 0; // variable to hold the red color

float greenValue = 0; // variable to hold the green color

float blueValue = 0; // variable to hold the blue color

// the setup() method runs once at the beginning of the program:

void setup() {

size(320, 240); // sets the size of the applet window

background(0); // sets the background of the window to black

fill(0); // sets the color to fill shapes with (0 = black)

smooth(); // draw with antialiased edges

}

// the draw() method runs repeatedly, as long as the applet window

// is open. It refreshes the window, and anything else you program

// it to do:

void draw() {

// Pick random colors for red, green, and blue:

redValue = random(255);

greenValue = random(255);

blueValue = random(255);

// set the line color:

stroke(redValue, greenValue, blueValue);

// draw when the mouse is up (to hell with conventions):

if (mousePressed == false) {

// draw a triangle:

triangle(mouseX, mouseY, width/2, height/2,pmouseX, pmouseY);

}

// erase when the mouse is down:

else {

background(0);

fill(0);

}

}

Hello