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Index › Programming Questions & Help › Syntax Questions › scale but maintain in the center
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scale but maintain in the center (Read 636 times)
mateooo
scale but maintain in the center
Jun 2nd, 2009, 8:10am  
hello i need to scale an sphere using iteration, but i need that in each iteration the new scaled sphere appears in the center. How can i do that?


there there are some pics so you can understand better
this is what i need to do:
http://fotosupload.com/mostrar.php?imagen=FuD89406_centroooo.png

and this is what my code is doing:

http://www.fotosupload.com/mostrar.php?imagen=FuD89408_no_center.png


any idea? I also need to do the same with lines


here is my code:


  for (int i=0 ; i < 5 ; i ++) {
      pushMatrix ();
      translate(40,22 );
      pushMatrix ();
       translate(i * 3, 0 );
      scale(1 , 1 + i);
      ellipse(22, 22, 22, 22);
     //line(0.5  , 0.5 ,  0.5 ,  6 );
      popMatrix();
      popMatrix();
}
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koogy
Re: scale but maintain in the center
Reply #1 - Jun 2nd, 2009, 10:15am  
try scaling before the translate (the way you have it the offset from 0,0 is also being scaled)
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mateooo
Re: scale but maintain in the center
Reply #2 - Jun 2nd, 2009, 10:31am  
koogy ive tried that but it doesnt work!!!
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PhiLho 
Re: scale but maintain in the center
Reply #3 - Jun 2nd, 2009, 12:02pm  
The problem is that you used coordinates in ellipse() call: when you do a transformation, you should always use 0, 0 coordinates.
Code:
size(500, 500);
smooth();
for (int i=0 ; i < 5 ; i ++) {
	pushMatrix();
	translate(100, 100);
	scale(1, 1 + i);
	translate(i * 8, 0);
	ellipse(0, 0, 22, 22);
	popMatrix();
}

Also there is no need for two push/popMatrix.
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WWW  
mateooo
Re: scale but maintain in the center
Reply #4 - Jun 2nd, 2009, 12:27pm  
amazing philho, many thanks!!!!
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