How Camp wrote:
> "Tom Austin" <taustin> wrote in message news:4474ae2b$1@news.povray.org...
> 
>> Using a 3D area laser scanner, separate 'scans' are collected at each 
>> location.
> 
> 
> Forgive the questions, but:  What sort of laser, how long does a typical 
> scan take, and what's the maximum resolution?
> 

	It's a time of flight laser that can gather about 20,000 data points a 
second.  It scans in a spherical grid (2 angles & a range).  The 
scanning window is about 80 degrees vertical and 340 horizontal.
Each of the scans in this animation is over 2 million data points - each 
raw scan file is over 17Mb.  A scan takes about 6 minutes to complete at 
this resolution.  The data is good to about 1/2 inch.

> 
> I don't suppose each scan has an absolute position reference?  You must know 
> something about their positions relative to each other, obviously, or you 
> wouldn't have been able to generate the fly-through like you did.
> 

We do not know anything about the positions of the scans in relation to 
each other except a hand sketch for rough positioning.  We have some 
software that neatly aligns the data automatically.  All we need to do 
is give it a very rough starting point.

Using survey points, we were able to align the data in a real coordinate 
system.


> Warp has dealt with meshes quite a bit, perhaps he's got some ideas for 
> joining them together...
> 

maybe....


LAter... Tom

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