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Ananth B.

Delphi Developer
Sat, 01 Oct 2005 22:06:38 GMT

Zoom to extents

Hi,
    Would anybody know a zoom to extents algorithm for 3D (OpenGL)?
I have a camera that uses gluLookAt to view a simple flat scene (this always
lies on XY) from -Z (forget complex camera placement. The camera moves
parallel and perpendicular to the XY plane only).
    I know the world coords of the bounding rect of the flat scene. Is there
some non-iterative way to do a zoom-to-extents? Moving the camera there is
simple enough, but its the zooming thing that I'd like to do with
calculations, and not iteratively.

Many thanks in advance,

Regards,
Ananth B.

 
Ananth B

Delphi Developer
Mon, 03 Oct 2005 17:44:45 GMT

Re:Zoom to extents


A big thanks goes to Dr. Steve Evans, who provided me with the necessary
information (via direct email).
Really, thanks a lot. (^_^)

Regards,
Ananth B.

Quote
"Ananth B." <ana...@agnisoft.com> wrote in message

news:3e9c145f@newsgroups.borland.com...
Quote
> Hi,
>     Would anybody know a zoom to extents algorithm for 3D (OpenGL)?
> I have a camera that uses gluLookAt to view a simple flat scene (this
always
> lies on XY) from -Z (forget complex camera placement. [snip]

steve evan

Delphi Developer
Mon, 03 Oct 2005 21:53:00 GMT

Re:Zoom to extents


I forgot to say, have you tried the glscene newsgroups?
  news://forums.talkto.net/glscene.general
  news://forums.talkto.net/glscene.support

Steve

Quote
"Ananth B." <ana...@agnisoft.com> wrote in message

news:3e9c145f@newsgroups.borland.com...
Quote
> Hi,
>     Would anybody know a zoom to extents algorithm for 3D (OpenGL)?
> I have a camera that uses gluLookAt to view a simple flat scene (this
always
> lies on XY) from -Z (forget complex camera placement. The camera moves
> parallel and perpendicular to the XY plane only).
>     I know the world coords of the bounding rect of the flat scene. Is
there
> some non-iterative way to do a zoom-to-extents? Moving the camera there is
> simple enough, but its the zooming thing that I'd like to do with
> calculations, and not iteratively.

> Many thanks in advance,

> Regards,
> Ananth B.

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