Re: Camera FoV

I can’t give you a code example but I’ll give you the scenario.

I have renderers implemented in Directx and OpenGL that output renders (images) to me.

In these renderers I can set any value as diagonal field of view to the camera.

What I wanna do is to use a low poly version of my 3d models in papervision, so the user can set the camera position in the scene, click on a button to render and I output an image of the same scene rendered using high poly 3d models on my renderers.

The default diagonal FoV that I use in the renderers is 25. The flash stage and the output image have the same size 622x310. I could synchronize the papervision camera with my renderers using the following formula to find the papervision camera focus:

var diagonalFOV:Number = 25;
var width:Number = 622;
var height:Number = 310;
var w:Number = width;
var h:Number = height;
var d:Number = Math.SQRT((w * w) + (h * h)) ;
var focalDistance:Number = d * Math.TAN(diagonalFOV / 2.0) ;

And I had to manually adjust the papervision camera zoom until it matches the rendered images.

I have the following questions:

1) Does the papervision camera focus represent the focal distance that we find in any standard 3D game library (DirectX/OpenGL) for camera settings?
2) How can I calculate automatically the papervision camera focus and zoom if I give you as input my stage size and diagonal field of view?

Thank you,

Marcelo Muniz