[Coding] camera zoom topic

hi

on d3d9 based games you normaly use D3DXMatrixPerspectiveFovLH and D3DXMatrixLookAtLH to implement your camera zooming in/out.

do you know another way of doing zoom in d3d9 without the use of D3DXMatrixPerspectiveFovLH and D3DXMatrixLookAtLH?

i'm not asking for src just drop me a hint :)

thx