[osg-users] Performing zooming and other navigations on geocentricvirtual earch?

Paul Melis paul at science.uva.nl
Tue Mar 24 08:42:54 PDT 2009


Paul Martz wrote:
>>> Zooming merely changes the field of view without changing the view
>>>       
> position.
>   
>>> Think of a photographer changing lenses on a camera without changing 
>>> his physical location. You change the projection matrix to change the 
>>> field of view, not the modelview matrix.
>>>   
>>>       
>> But that's *your* definition of zooming...
>>     
>
> No, it's the computer graphics industry definition of "zoom", as defined by
> Foley and Van Dam, the Real-Time Rendering book, and the OpenGL red book.
> It's a word that has its root in photography, which shares the same
> definition. Zooming magnifies an image; it does not affect the view
> position.
>
> Words mean things. Programming is a very precise activity and we should
> select our words carefully when describing what we are trying to do. I would
> be doing the OP a disservice if I did not correct his usage and inform him.
>   
Sorry for yapping about this, I'm having a bad day (and can't really 
figure out what is the real issue in my head...)

Paul



More information about the osg-users mailing list