Posted by gouessej on Jul 26, 2016; 2:33pm
URL: https://forum.jogamp.org/Object-rendered-after-transparent-image-are-not-shown-tp4036968p4036974.html

Actually, you should draw the transparent parts at last, the rendering order matters. You can look at this tutorial:
http://www.opengl-tutorial.org/intermediate-tutorials/tutorial-10-transparency/

I wouldn't use those methods except with partially transparent triangles, for example a dirty window glass. Using them with fully transparent triangles is too much complicated.