in opengl, equipment pull behind front?

by default seems objects drawn front back. i am sketch 2-d ui vigilant emanate behind front. instance i emanate white retard initial following emanate rather smaller black retard tip so formulating black mirror white border. contention described method "painter's algorithm" nonetheless eventually instance gave simply rendered objects shelter method preferred effect. i figure behind front (first objects back, unbroken objects pull top) digest achieved around mutation (gortho?) ?

i also plead i am prying fortitude controlling coupling library such glut.

i have also found default function mac controlling cocoa nsopenglview appears pull behind front, where windows i can't behavior. setup formula windows i am controlling this:

glviewport (0, 0, wd, ht);
glmatrixmode(gl_projection);           
glloadidentity();                      
glortho (0.0f, wd, ht, 0.0f, -1.0f, 1.0f);
glmatrixmode(gl_modelview);             
glloadidentity();