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martinzwigl
08-13-2001, 03:09 AM
Hi Folks

in my animations -physically- i want to be "correct" as much as possible. has anybody of you read anything about human eye and field of view (meaning how to choose the frustum) or how "far" one can sea and similar data.
another question: if one has to cover really a large terrain mapping of the earth, how important is it to have differernt spacing between the drawn points according to the spacing of latitude and longitude.

thanks for your insights,
martin

AndersO
08-14-2001, 05:43 AM
Basicly try different degrees of fov and pick the one you feel ok.

The actual fov that you got focus on is probably small.. Try this, hold your eyes on one word in this text, then try to read on word on either left or right without moving your eyes. Damn hard right?. A small fov like that is obviously not the way to go. Maybe a "physically correct" fov would be to measure the typically length from the monitor to your eyeball and then from your eyeball position measure the angle from the left to the right side of the monitor.

But that would probably not look ok either (too small), since you see allot more beyond that angle, though blurred.

Another geeky way to find out the fov, look straight ahead with your arms streteched out to left and right. Then gradually rotate your arms inwards, when you see your hands stop and measure the angle between your arms.. http://www.opengl.org/discussion_boards/ubb/smile.gif

Close to 180 degrees?.. That wouldn't work that good.. (Too large)

I think that most fps shooters use a 90 degree fov as default. Seems ok'ish to me.


Spacing between latitude and longitude?.. You mean like how to project a sphere to 2D/screen?.. You could allways calculate xyz out of the latitude and longitude and let opengl draw the sphere.