You say that I didn't provide you with w and h but isn't that my 1680 and 1050 or am I missing a step?
You wrote that the texture is 1680 by 1050 pixels which is a resolution. You wrote that the aspect ratio of the plane is 1680/1050 which is, well just a ratio. If you meant that the edge lengths of the plane are 1680 by 1050 length units in worlds space, than all is fine.
Also doesn't happycoders give me the z distance in pixels and not translated to z axis?
Dimension analysis of the formula:
[ z ] = [ h ] * [ tan(a) ]
where
[ tan(a) ] = 1
so
[ z ] = [ h ]
With respect to my first post above, where I hinted at the need for a plane in world space, you get
[ z ] = [ h ] = 1 lu (which means length unit)
So, if you feed that h as world dimension, you get that world dimension back.
