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David
02-02-2001, 02:42 AM
gluPerspective(m_FOV*m_fZoom, m_AspectRatio, m_NearClipPlane, m_FarClipPlane);

m_fZoom is a zoom factor (1.0 = normal) and changing it increases / decreases my zoom.
This is fine but I need to know how to do a specific zoom such as 4x and 10x (as in a pair of binoculars has a 10x zoom)

Anybody know how I do this?

Michael Steinberg
02-02-2001, 04:47 AM
Well, let's say you've got a 90 degrees fov normally. 45 degrees is the half of it, and you will only be able to see the half in either direction which should be equal to a 2x zoom.

0.5 - 2x
0.25 - 4x

Hope I'm right.

link19
02-02-2001, 05:46 AM
Excuse my ignorance...but im interested in this as well and do not know what FOV refers to?? http://www.opengl.org/discussion_boards/ubb/redface.gif

Starnut coder
02-02-2001, 07:09 AM
do not know what FOV refers to?? http://www.opengl.org/discussion_boards/ubb/redface.gif[/B]

Well as far as i know FOV is the Angel a camera has. This Angel affects the size of the lens.
As the size of the lens is:
FOV*(pi/180)

If the FOV is bigger, the lens gets bigger and with that the amount you can see gets bigger. The bigger your lens is the more you can see and the less you are soomed.

-Starnut

Kranomano
02-04-2001, 02:09 PM
A fisheye lens effect can also be done by changing the FOV to a large number, like, say, 140. FYI, FOV = Field Of View.