How to do gluUnProject() with XCode 8.x?

Question

I basically want to do the trick described here - figuring out world coords given screen coords.

However, the status of gluUnProject() is very unclear. I can see that it is supposed to be provided by the "OpenGL Utility" library (glu).

This old looking documentation says that Apple implement glu. The link it gives points to another page that says XCode is supposed to supply all this.

XCode 8.x brings with it an OpenGLES framework. However, the only headers I can find are the most basic ones (gl.h and glext.h).

No glu.h

So how does one do gluUnProject(), or any equivalent means of working out the world coords from screen coords?

Answer 1

The answer is "use GLKMathUnproject()" from GLKit.