Picking points using OpenGL

I have an algorithm to select triangles and it works quite well, but when I tried to apply this code to select points it didn’t work.
Is it because points are too small to be picked?
Does anyone know how you can pick points?


If you mean picking by the mouse, then try this, which I used with points as well as with larger objects:

If the eye/camera is at the origin(0,0,0) then the mouse coordinates will be (after you map them to the range [-1,1]) say, Mouse=(x,y,ScreenZ). If the point is determined by the vector V(XP,XY,XZ) then this point should be selected if it satisfied this condition:

Mouse . V > F*Length(Mouse)*Length(V)

where the dot (.) is the dot product operator
and F is a real number between 0 and 1. The closer F is to 1 the more accurate you’ll pick, but picking may became more difficult.

I will try it and then tell you the result.
Thanks for the tip!