In my game i use glFont to display my text, but i originally had a problem that surrounding each letter was a black box. I used glBlendFunc(GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA) to solve this.
However this only works properly when i want to display my text in front of a 3D object. If i display the text in-front of my in-game interfaces (drawn in 2D ortho mode) the black boxes are removed, however so are sections of the interface where the black boxes would have been.
i.e. it produces ‘holes’ in the interface and lets you see the through to the rest of the game world, where ideally i want my interface with the text on top.
I dont have a 2D interface in mine i just want the 3D text to display properly.
with depthtest enabled the text flickers
with depthtest disabled the text gets drawn infront of other objects. i see no way to solve this unless i calculate which object is closest to me.