Hi Phil
I'm not familiar with your projection so I may be way out here but....
MapInfo chops the Minimum bounding rectangle for your Map projection
into 4000 million pieces ( a LONG value )( ie +- 2GB). If you do not set
a MBR then the smallest unit that you can use can be quite large.
When you move around your map although you think you can move anywhere
there is an "invisible grid" based on the smallest unit above. If
different layers are to different projections then it may be that you
cannot snap to points that you can see on another layer.
Some GIS and CAD systems (like AutoCAD ) use double precision so you can
store what you like but internally the mapinfo MAP file holds
coordinates in 4 byte long.
The only way to improve accuracy is to set as small a Bounding Rectangle
as possible for your map. Here in UK we can set down to 1600 Km x 1600
Km and can get a minimum unit of half a millimetre, so we can draw lines
pretty accurately although MapInfo uses long integers. I personally use
a projection that stores cordinates in units of 1 millimetre.
If you are drawing relatively short lines and your smallest unit is say
100 millimetres this might account for the behaviour you are seeing.
Hope this helps.
Bob
In message <[EMAIL PROTECTED]>,
Uhl, Philip/SLC <[EMAIL PROTECTED]> writes
>Hi,
>
>I created points from a table. The coordinate system is State Plane NAD83
>(U.S. Survey feet). I know distances from these points to other features I
>want to draw in. As I draw these features, I'm noticing some weird
>behavior. I'll draw a line, double-click on it, then set its length to 17.5
>ft. When I double-click on it again it says the line is 17.4 ft and there
>is nothing I can do to change it. Also, all the lines I draw snap to some
>predefined angles. Anyone know of a remedy?
>
>My system:
>MI Pro. ver 5.0.1
>Window NT 4.0
>
>Thanks,
>
>Phil Uhl
>Salt Lake City
>
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--
Bob Young
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