[Closed] Caculate camera viewport size?

Search for Martin Breidt’s ImagePlane script. It’s free!

Try this:

(
	fn CreateCameraFrustumPlane cam dist =
	(
		verticalFOV = 2.0 * atan (tan(cam.fov/2.0) / getRendImageAspect())
		width  = 2 * dist * tan(cam.fov/2.0)
		length = 2 * dist * tan(verticalFOV/2.0)
		plane width:width length:length dir:cam.dir pos:(cam.pos-(dist*cam.dir))
	)

	theCamera = $
	CreateCameraFrustumPlane theCamera theCamera.targetdistance
)

to be a little more correct:

fn cameraFrustumTM cam dist: = if isvalidnode cam and iskindof cam Camera do
(
	if dist == unsupplied do dist = cam.baseobject.targetDistance
	x = 2 * dist * tan (cam.fov/2)
	y = x / getRendImageAspect()
	(translate (scalematrix [x,y,1]) [0,0,-dist]) * cam.transform
)
tm = cameraFrustumTM $ -- where selection is a camera
p = plane width:1 length:1 name:"frustum_plane" transform:tm 

More correct?

i don’t have max around to test it but if my logic is correct the:

(freecamera()).targetdistance

has to return undefined

but… i’ve thought a little more. you are right.

a user can override ‘targetdistance’ property. so it’s safer to ask this property from the object instead of its base.
but in this case we have to check that the object returns anything that makes sense

I know, and so the function I wrote does not use the ‘targetdistance’ property.

We should ask the developers to remove it from MXS then.

BTW, ‘targetdistance’ is a buggy property. In your function you should verify the camera type before assuming it will return the correct value.

fair enough… but see a post above. in general case we should just ask this property and check if it makes a sense.

Ok, you win…
…
No, you don’t