While Roatating

[Dastagir]

hi,

i'm around 800000 lines.while rotating this the image get cuts at some position.i have given my projection as perspective.
help me regarding this.i have attached my screen shot in this link Screenshot (http://cid-6a2ae6c2240ebc3b.office.live.com/self.aspx/Public/Screenshot.png)

[ZbuffeR]

This sound like the classic "moved camera in GL_PROJECTION mode" :
http://www.opengl.org/resources/faq/technical/projection_abuse.php

Or the near clip plane is too far, it is hard to see in your picture.