On 1/23/12 1:18 PM, Javier Herrero wrote:
El 23/01/2012 21:43, Jim Lux escribió:
One is where you "lay the iphone on the table" in a fixed position.
One could use the internal accelerometers to determine "level", but I
don't think you could tell orientation, unless, perhaps, you can see
circumpolar stars? That is, by watching the movement of the
stars/planets through the field of view over some hours, could you
figure it out? Or is there some fundamental ambiguity.
I don't know about the iPhone, but I've seen an HTC with a funny
application that, when you point anywhere in the sky, it shows you the
constellations that are there. Even if you point it to ground, it shows
you the constellations in the other hemisphere :) I don't remember if
the application is this http://www.google.com/mobile/skymap/ or
something similar, but in any case, the phone knows its orientation
quite good (well... also depends on the phone to have the right time, of
course... :) )
yes, Pocket Universe (pUniverse) does this quite nicely (esp on the iPad)
But it uses the magnetic compass (and GPS) as well as orientation.
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