Outer elements selection

[AeroSujan]

Dear Friends
I have created a mesh GL_QUAD through glDrawElement and stored the whole mesh into a glNewList with index 1. Now when I call glCallList(1) I am able to get the mesh. Now the problem is I want select all the QUAD elements those are at the boundary.That extreme outer elements I want to get and basically I need all points that lie outerside.

Is there anyway to recognize which elements are outmost and get them and get the outer points only.

Any help would be highly appreciated.
Thanks
sujan

[AdrianPi]

Is there anyway to recognize which elements are outmost and get them and get the outer points only.

No, there is no such a feature in OpenGL

[AeroSujan]

So what best way I can retrive the outer elements. I feel when I am creating the elements that time the last element in every column I have to keep track as the outer elements and then taking the outer points. Is this process fine ..

Can I get your suggestions ?