Add 0's to date/time in the filename with saveFrame()

bhuhnke

Hey there! This is my first post here, already found a lot of helpful stuff here just reading. I was just wondering if this is something I'm doing wrong or if it is not intended.

When I use saveFrame() to save a projects current canvas, I usually wanna have this result: Projectname-20161230-184555.png which usually corresponds to following line:

saveFrame(Project+"-"+year()+month()+day()+"-"+hour()+minute()+second()+".png");

(yes, I'm from Europe, I like my months in front of my days :P)

The only real issue is that every function returns exactly what it is supposed to (which is totally right): When it is 8 am for example it returns an 8 when I call hour(). If I want to auto-sort the files though I need the 0 in front of every digit that doesnt have 2 digits, so I came up with this (quite hacky) solution (titled as void savePNG() because it isn't a one-liner anymore so I can call it):

void savePNG() {
  if (second()<10) {
    saveFrame(Project+"-"+year()+month()+day()+"-"+hour()+minute()+"0"+second()+".png");
  } else if (minute()<10) {
    saveFrame(Project+"-"+year()+month()+day()+"-"+hour()+"0"+minute()+second()+".png");
  } else if (hour()<10) {
    saveFrame(Project+"-"+year()+month()+day()+"-"+"0"+hour()+minute()+second()+".png");
  } else if (minute()<10 && second()<10) {
    saveFrame(Project+"-"+year()+month()+day()+"-"+hour()+"0"+"0"+minute()+"0"+second()+".png");
  } else if (second()<10 && hour()<10) {
    saveFrame(Project+"-"+year()+month()+day()+"-"+"0"+hour()+minute()+"0"+second()+".png");
  } else if (minute()<10 && hour()<10) {
    saveFrame(Project+"-"+year()+month()+day()+"-"+"0"+hour()+"0"+minute()+second()+".png");
  } else if (second()<10 && minute()<10 && hour()<10) {
    saveFrame(Project+"-"+year()+month()+day()+"-"+"0"+hour()+"0"+minute()+"0"+second()+".png");
  } else {
    saveFrame(Project+"-"+year()+month()+day()+"-"+hour()+minute()+second()+".png");
  }
}

And yes, I forgot about months and days here aswell.

Is there an easier way or is that just the way it's supposed to be?

GoToLoop

https://Processing.org/reference/nf_.html

bhuhnke

Thx for your post @GoToLoop. That seems to be another way to add the 0 to the left of the number. I didn't know that one before, but it doesn't make the code smoother in any way because I still have to go through all those if's

GoToLoop

// Forum.Processing.org/two/discussion/16001/
// add-0-s-to-date-time-in-the-filename-with-saveframe#Item_3

// GoToLoop 2016-Apr-13

void setup() {
  background((color) random(#000000));

  String stamp = timestamp("Project", ".png");
  println(stamp);

  String path = dataPath(stamp);
  println(path);

  saveFrame(path);
  //saveFrame( dataPath( timestamp("Project", ".png") ) );

  exit();
}

static final String timestamp(final String name, final String ext) {
  return name + "-" + year() + nf(month(), 2) + nf(day(), 2) +
    "-" + nf(hour(), 2) + nf(minute(), 2) + nf(second(), 2) + ext;
}

koogs

Java's simpleDateFormat was made for this.

bhuhnke

Thank you @GoToLoop and @koogs for your posts. I'm really sorry @GoToLoop that I couldn't wrap my head around what you posted yesterday, a lot was going on. It struck me when I read line 22 of your example that nf() just adds a character (0) when it is not already 2 characters wide... thats pure genius and exactly what I was looking for. Also learned something new with static and final, pretty cool stuff! Thank you very much!

GoToLoop

Also learned something new with static and final, pretty cool stuff!

Just an observation: Neither static nor final are necessary for the definition of function timestamp().

1. https://Processing.org/reference/static.html
2. https://Processing.org/reference/final.html

I've just declared timestamp() as static to indicate that it's a stateless utility function.
It means timestamp() only works w/ the parameters passed to it.
And it can't access nor depend on the state of the sketch's canvas.