pushMatrix saves the current matrix to the stack and when you call popMatrix it just restores it back..
im not sure what do you want to do, would you explain ?

this is one easy way to do that.. get matrix and take translation vector.. other way would be for you to use parent children relationship to do transformation yourself..
so far it prints the position.. you should create an array and save them for later use.. i think this is what u were looking for.



import processing.opengl.*;
import javax.media.opengl.*;
import javax.media.opengl.glu.*;


// my programm
float a  = 0.0;
float inc = TWO_PI/30;
float dreher;



PGraphicsOpenGL pgl;
GL opengl;
GLU glu;


float[] m = new float[16];

//fluegelkreise akrivieren
Fluegelkreis[] kreiseF = new Fluegelkreis[10];

int zufall =0;
int kugelZaehler=0;

float posx =0;
float posy =0;

void setup()
{
 size(400,400, OPENGL);
 
 pgl = ((PGraphicsOpenGL)g);
 opengl = pgl.gl;
 glu = ((PGraphicsOpenGL)g).glu;


 smooth();
 frameRate(25);
//10 Fluegelkreise machen
 for (int i=0;i<10;i++)  
 {
   kreiseF[i] = new Fluegelkreis();
 }
}

void draw()
{
 background(254);
 // gleichmässige Bewegung
 dreher = sin(a)/10;
 a+= inc;

 // Kugelfigur zeichnen  
 initKugelfig(200);

// Fluegelkugeln produzieren?
 zufall = int (random(20));
 if (zufall==2) {
kreiseF[kugelZaehler].aktiv = 1;
kreiseF[kugelZaehler].y = height - int(random(150)) -40;
if (kugelZaehler == 9)
{
  kugelZaehler=0;
} else
{
kugelZaehler+=1;
}
 }

//Fluegelkugeln bewegen
for (int i=0;i<10;i++)
 {
   if (kreiseF[i].aktiv == 1)
   {
kreiseF[i].walk();
kreiseF[i].render();
   }
 }
}

class Fluegelkreis
{
 int y,x;
 int aktiv = 0;

 Fluegelkreis ()
 {
   y = 0;
   x = 0;
   aktiv = 0;
 }  
 void render()
 {
   fill(0,0,200,150);
   noStroke();
   ellipseMode(CENTER);
   ellipse(x,y,30,30);
   
   if (x>width)
   {
aktiv =0;
x=0;
   }
 }  
 void walk()
 {
   x+= 5;
 }
}

   
void initKugelfig (int x)
{
 pushMatrix();
 translate(x, height);
 posy = 0;  
 drawKugelfig(0);  
 popMatrix();  
}

void drawKugelfig(int grad)
{
 pushMatrix();
 int kreisrad = 40-grad*4;
 ellipseMode(CENTER);
 noStroke();
 fill(250,0,0,180);  

 ellipse(0,0,kreisrad,kreisrad);

 rotate(dreher);
 translate(0,-kreisrad);
 

 //-------------------------------
 //  Get the modelview matrix and extract the position vector
 //-------------------------------
 opengl = pgl.beginGL();
 // get the current modelview matrix
 opengl.glGetFloatv( GL.GL_MODELVIEW_MATRIX , m, 0 );  
 pgl.endGL();
 float x = m[12];
 float y = m[13];
 float z = m[14];
 println( "X="+x );
 println( "Y="+y );
 println( "Z="+z );
 

 if(grad<7){drawKugelfig(grad+1);}
 popMatrix();
}