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MAPINFO-L
It is just a case of defining a custom Affine projection to represent your non-earth data.
Essentially this describes transformation
parameters to get from real earth coordinates to your local coordinate system.
Your non-earth coordinate values will be the same, but
everything will now also plot in the correct position on the earths surface and can be overlayed with real earth data.
What you need are the Affine parameters a,b,c,d,e,f for:
X' = Ax+By+C
Y' = Dx+Ey+F
or
X' = Cos(theta)*x+Sin(Theta)*y+c
Y' = -Sin(theta)*x+Cos(Theta)*y+f
where theta is the angle of the coordinate system, C is the offset in the x direction and F the offset in the Y
direction.
These can be used in a custom projection (in this case based on Australian Map Grid 50, datum AGD84):
"My Affine Projection", 3008, 13, 7, 117, 0, 0.9996, 500000, 10000000, 7, A, B, C, D, E, F, Bounds Clause
Or with real numbers:
"My Affine Projection", 3008, 13, 7, 117, 0, 0.9996, 500000, 10000000, 7, 0.780100691704, 0.619057142912, -5308307.365,
-0.619057142912, 0.780100691704, -5516110.998, 0, 0, 500000, 500000
To help with the parameters my Affine calculator should be of use. It is an ActiveX component, so you will need to use
MS Internet
Explorer and also set your security settings to low:
http://members.iinet.net.au/~mose/prod03.html
Let me know if you need any further help.
Regards
Neil Moseley
Geodata Computing Services
mailto:mose@iinet.net.au
http://members.iinet.net.au/~mose/
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