[Therion] Fixed corner co-ordinates on a map

[Andrew Atkinson]

Hi all

I am looking to try and generate an output which will always have the 
same co-ordinates.

I am try to do this as we have a rapidly expanding cave system which we 
would like to plot on google earth (or the likes) using Bill Chadwicks 
map of the Mendips

http://www.bdcc.co.uk/mendip.html

Now after consulting with Bill it appears if we predifine the size of 
the plot the crunching, just becomes computer power, so we can update 
then map as data comes in, full instructions are at

http://www.bdcc.co.uk/GoogleCrunch/Crunch.htm

Any hints welcome, one idea I have had is to use a 'blank' bit map as a 
surface, does it always displace the whole surface? This is something 
that I am having dificulty understanding the instructions for

thanks

Andrew

PS as soon as we fix the corners we will go back to the old fashiones 
paper problem of going off the sides....