Hi Jason,

On Tue, May 19, 2009 at 4:51 PM, Jason Daly <[email protected]> wrote:
> Robert Osfield wrote:
>>
>> In hindsight mixing of ELEVATION and AZIM in TerrainManipuilator is
>> not ideal
>
> I'm not so sure, I think the two terms (Azimuth and Elevation) are
> essentially interchangeable when you're dealing with a manipulator like
> this.  It just depends on your point of view (are you manipulating the
> camera from the center of the sphere, or are you orbiting and aiming the
> camera "downward"?)
>
> There are occasions in real life where you deal with azimuth and elevation
> together.  Ever installed a satellite dish?

Not yet :-)

> I'm actually not sure that Zenith is appropriate, based on the Wikipedia
> page you cited.  Shouldn't it be "Inclination" instead?

Yes Zenith isn't necessarily the most appropriate name, given zenith
is typically the up direction, and the "Zenith Angle" being
specifically what is be controlled in the SphericalManipulator
context.  From the article:

"and the inclination may be called colatitude, zenith angle, normal
angle, or polar angle."

We could also change the SphericalManipulator::set/getZenith property
to s/getInclination() or s/getElevation().  In the both the later
cases I'd be "inclined" to measure both from the horizontal plane
rather than the Zenith/up direction - as a 0 degree elevation or
inclination would relate to looking horizontally.  Changing this would
be just require us to rename methods/variables and change some of the
internal maths.

Thoughts?
Robert.
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