Sending newly created object behind previously drawn objects

Hi,

What is the best way to send a newly created object behind existing objects?

A simple call of pushing a new matrix and translating the matrix with say a -100 z value does not appear to work.

Thank you!
Doug

  
  
ofPushMatrix();  
	ofTranslate(0,0,-110);  
	ofSetColor(255,0,0);  
	int increment = ofGetWidth()/60;  
	ofRect(0,0,increment*ofGetSeconds(),ofGetHeight());  
	ofPopMatrix();  
  

The first thing is you have to know, is always render from back to front. Because openGL is not smart and when you draw will store in viewport these pixels in last step of render pipeline.

I hope to clarify you doubts.

best,

Mar