Rotation pivot point & view matrix problem

Hi all,

I am newbie of opengl.
I have a problem regarding view matrix change after setting pivot location.
When I change pivot point (Alt+Mouse Left Button)for rotation then camera center position moved to pivot position.
Please let me know what problem in my code. :sob:

archive.tcltk.co.kr/files/tmp/Main.cpp
archive.tcltk.co.kr/files/tmp/reproduce.mp4

Please copy & paste to your browser.

Thanks & Regards.

Please be sure to read our posting guidelines. Include in your question, what you have tried, where you think the error in your code might be, exactly what the expected outcome is. The more you put into your question, the more you will get out of an answer.