Need help with printing (paper, to an actual printer)

Processing Coding Questions
1

<I’m an art student that got a Processing project in three stages for my Digital Art Class. No a programmer by myself.
I ended up making a humble but nice autogerenating art code. What i need for the instalation is Processing taking a screenshot and deliver it straight to printing, not even going through the printer setup part.
I keep googling and googling and can’t find an answer for that.
It’s possible to get a brief explanation/code guide for how can i achieve it?

Thanks for reading.

There is one of the codes i’ll run:

float x;
float y;
float variacionX;
float variacionY;
float xAnterior;
float yAnterior;
int Animaciones=48;

void setup() {
size(1360,768);

x=new float[Animaciones];
y=new float[Animaciones];
variacionX=new float[Animaciones];
variacionY=new float[Animaciones];
xAnterior=new float[Animaciones];
yAnterior=new float[Animaciones];

for (int i=0;i<Animaciones;i++) {
x[i]=random(width);
y[i]=random(height);
xAnterior[i]=x[i];
yAnterior[i]=y[i];
}

background(0);
}

void draw() {
if (mousePressed) {
background(0);
}
else {
for (int i=0;i<Animaciones;i++) {
variacionX[i] = random(-5,5);
x[i]+=variacionX[i];
variacionY[i]=random(-5,5);
y[i]+=variacionY[i];

if (x[i]<0) {
  x[i]=0;
} else if (x[i]>width) {
  x[i]=width;
}

if (y[i]<0) {
  y[i]=0;
} else if (y[i]>height) {
  y[i]=height;
}

stroke(255,20);
line(xAnterior[i],yAnterior[i],x[i],y[i]);
xAnterior[i]=x[i];
yAnterior[i]=y[i];

}
}
}

1 Like
2

The following source code works on my system (Mac). You’ll need to change ‘mySaveStr’ to reflect your filename and system:

void setup() {
  size(400, 400);
  surface.setTitle("Mouse press to send to printer.");
  PImage img = createImage(264, 264, RGB);
  img.loadPixels();
  for (int i = 0; i < img.pixels.length; i++) {
    img.pixels[i] = color(0, 90, 102);
  }
  img.updatePixels();
  image(img, 68, 68);
}

void draw() {
}

void mousePressed() {
// Edit this string for your system
  String mySaveStr = "/Users/yourName/Desktop/image.png";
  save(mySaveStr);
  exec("lp", mySaveStr);
  println("Image sent to printer.");
}
1 Like
3

Well, thanks for taking your time. The deal is, there is no filename, there should be only clipboard data.
What a i need is directly print what’s on screen by using keyPressed or mousePressed.

4

With this technique, if you don’t want to save the image then you would have to print it and then delete the file with a delay() in between.

void mousePressed() {
  String mySaveStr = "/Users/xxxxxx/Desktop/image2.png";
  save(mySaveStr);
  exec("lp", mySaveStr);
  println("Image sent to printer.");
  delay(1000);
  File imgFile = new File(mySaveStr);
  if (imgFile.exists()) {
    imgFile.delete();
    println("imgFile deleted.");
  }
}

There are other ways of printing image files using Java, but they are more complex and you would have to do your drawing on one of their controls, for example, a JPanel.

5

Thanks a lot, man. I can work with this.
If i crack exactly what i mean for this installations, i’ll share the code for anyone who wants something like that.