Picking without depth-buffer information[SOLVED]

[potatosoftware]

What are the less difficult ways to implement picking without relying on the depth buffer information ?

I was successfully using gluUnproject untill I faced an unresolved issue with depth buffer being cleared after I blend an FBO.

That's why I unfortunately have to disregard solutions based on the depth buffer.

Thanks in advance.

[potatosoftware]

For the information,
my 3D scene consists in a sphere (virtual globe) with lines on it representing the political boundaries between countries of the world.

So I just need to pick the point on the sphere that coincides with the mouse position.
Once I get the x,y,z of that point, I can easily deduce the longitude/latitude which are my final goal.

[david_f_knight]

Take a look here:
http://www.opengl.org/discussion_boards/...4748#Post284748 (http://www.opengl.org/discussion_boards/ubbthreads.php?ubb=showflat&Main=55041&Number=2847 48#Post284748)

[potatosoftware]

Thank. I just solved my issue by calculating the intersection between my scene sphere and the line joining the far/near points coinciding with cur mouse pos.