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Index › Programming Questions & Help › Programs › Rotate Image around Center
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Rotate Image around Center (Read 3507 times)
badoli
Rotate Image around Center
Sep 2nd, 2009, 9:34am  
Hey there

I'm new here and i have a little question: Is it possible to rotate an image around it's center? If i do something like...

Code:
float counter;
PImage img;

void setup()
{
  counter=0.0;
  size(300,300);
  img=loadImage("brownplane.png");
}

void draw()
{
  background(0);
  counter++;
  translate(width/2-img.width/2, height/2-img.height/2);
  rotate(counter*TWO_PI/360);
  // rect(-26, -26, 52, 52);
  image(img,0,0);
}


...it ends up rotating around it's upper left corner. Is it possible to define something like a pivot? I couldn't find anything in the documentation so far.

Thanks in advance!
Oliver
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PhiLho 
Re: Rotate Image around Center
Reply #1 - Sep 2nd, 2009, 9:44am  
I wish I was paid € 1 each time I see this question. I would be rich now... (well, not so much, actually).

Should go in a FAQ...

You weren't so far, you just have to translate to half the image size (or to the point you want to rotate around) after the rotation:

 translate(width/2, height/2);
 rotate(counter*TWO_PI/360);
 translate(-img.width/2, -img.height/2);
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badoli
Re: Rotate Image around Center
Reply #2 - Sep 2nd, 2009, 9:55am  
Quote:
I wish I was paid € 1 each time I see this question.


I tried to search the forum for "image", "center" and "rotate", but didn't get any results. Hmmm... whatever, thanks a lot!
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PhiLho 
Re: Rotate Image around Center
Reply #3 - Sep 2nd, 2009, 10:21am  
Don't worry, it wasn't a reproach, more like a hint for the FAQ (or reference).
The problem being quite generic, it is hard to search (unlike a rare function name).

Note: for some reason (performance!), search is limited to week-old messages. You have to remember to set it to (all posts). And even so, no obvious answer.
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