as i didnt get the help i needed in the beginners forum i try here again
and just for that start i CANT use glut functions so i cant use something like GLUunproject() to solve my problemâ€¦

ok here we go hehe:

hi guys i need your help

i got a simple problemâ€¦
i got a 3d model displayedâ€¦
now want i want is, clicking on the model with the mouse and getting the coordinates of the nearest vertex to the mouse pointer.

in other words i need a selection-vertex function which is included in every 3d modelling pogramm.

i know i have to caculate from 2d mouse coords to 3d model coordsâ€¦ but i dont know how!!!

have you got any tutorials on this ??
or can you write me the basics?

p.s. i cannot use any glut functions only opengl!
glut is not allowed in my c++ code (dont ask why )

So you have to do the same as the gluunproject function does. It is simple matrix multiplication. Just have a look at the input parameters of the gluunproject. Itâ€™s two matrices and the viewport. Shouldnâ€™t be to hard to figure out the reverse matrix.
An easier way would be to download the MESA source code, which is a software implementation of OpenGL. Youâ€™ll sure find the gluunproject source code there.

Maybe you should wonder what links will give google if you type â€śmouse selection openglâ€ť.

I guess you will find what you need â€¦ if not, have a closer look . And if still not, go on opengl.org (second result in google) for such basic topics.