Margus Ramst wrote:
>The standard perspective camera traces rays from a fixed viewpoint, mapping
>samples to a rectangle. Because the horisontal and vertical angle between
camera
>rays remains constant, they do not hit the rectangle at constant intervals.
>Instead, they are positioned more sparsely towards the edges of the
rectangle.
>This is what causes the distortion of distances (stretching) I mentioned
>earlier.

I think it's the other way around.
The rays *does* hit the rectangle at constant intervals, the horisontal and
vertical angle between camera rays *doesn't* remains constant. *That* is
what causes the distortion of distances.
An example: When the camera is perpendicular to a plane with a checker
pattern, the checker pattern is NOT distorted.

But if you imagined a *sphere* around the camera, *then* the rays would be
positioned more sparsely towards the sides.

Well, at least I think so :-)

Greetings,

Rune

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