Where are the draw calls of the OpenGL backend?

[PucklaJ]

First I want to say: Thank you for this amazing library. This is exactly what I need.

I want to use this library with OpenGL to render a GUI. I would like to have hardware acceleration which draw2d provides via draw2dgl. But this backend is implemented in OpenGL 1.0 and therefore you are limited to a Context of OpenGL 2.1 at max. If you want to have nice shader effects or if your hardware does not support immediate mode rendering, you have a problem. Therefore I would like to port the OpenGL backend to OpenGL ES 2 to also get better support on ARM SoCs. Now I am wondering: Where is the code that actually calls OpenGL? All I can find are a few lines in gc.go that render lines. But where are the triangles getting rendered?

This information would be very appreciated.