Qt5 QGLWidget rendertext problems

hi,

i am having issues with the QGLWidget rendertext function. specifically, if i draw filled polygons then even strings which should be "in front" of the polygons do not appear. i have modified the simple hellogl program from Qt to demonstrate the problem please see the attached zip file.

Attachment 13273

or u can download the zip file from this link: https://we.tl/t-9GYeqlzvI6

please download and unzip it will create a directory simple with the code and a .pro file on which to run qmake.

u can use the left mouse or sliders to rotate and then u should see the strings when the quad is no longer hiding the strings. string 1 should appear on startup but it doesn't.

thanks for any help.