"Mike Lane" kirjoitti
viestissä:0001HW.C1812AF5000B7897F04075B0@news.cable.ntlworld.com...
>
> It's hard to say. Navteq maps used by many GPS systems contain little
> topographical detail, but have an awful lot of data on the roads
> themselves which paper maps will not have. As well as the basic
Space is an issue in road maps. For instance Garmin (Navteq dbase) City
Navigator road map for Western Europe project all of Finland in size 110 MB.
Even not so detailed topographic maps would require roughly 10 or so times
more space. For instance a third party toporaphic atlas for Finland called
Vapaa-ajan kartta is very much like that.
And naturally speed is also a critical issue: typically terminals are built
around a processor which is not decently able to calculate zillions of
vectors to faciliate a frame of a topographic image and project it on
screen. These processes should be repeated in high frequency in order to pan
the map fast enough to keep the motor vehicle which is moving at velocity of
120 km/h on the visible part of the map all the time. Response times would
be far too lengthy so that instant mapping would do any good. Naturally
processing power is increasing all the time and perhaps already today
fastest recreational terminals (other than PCs) are able to instruct
motorists on detailed topographic maps.
Also, the size of most screens constitutes a bottle neck: it wouldn't be
anyhow beneficial to stare complex drawings on surface of that tiny three
inch screen. It would be quite a mesh indeed. Naturally a very high
resolution would be a solution but on the other hand that would require
lots of processing power......
All in all, as long as we don't have too fancy gadgets, we can say that most
motorist are willing to drive from one address to the next one using solely
a road network. They don't very much care about topographic features on the
map. It isn't too relevant.
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