Do you know if the object variables also unbounded as well?.... It could 
explain some of the  problems with object processing that I have been 
having with finding coincident points.   Could also be the cause of the 
GPFs I've been getting with merging using projected data into a variable.

Rob.



-----Original Message-----
From:   Steve Wallace [SMTP:[EMAIL PROTECTED]]
Sent:   Friday, November 19, 1999 10:46 AM
To:     MapInfo-L
Subject:        MI Problem discovered w/Bounds Clause

Something that might interest those of you who use the MapInfo "Bounds"
clause to increase the precision of your maps -- don't use the Cosmetic
Layer to transfer data around. I had been wondering why some of my
points/lines would move around from time to time. The distances were very
small, to the point where some might argue, "Why does it matter?" But the
problem is, the Object Processing notices these small differences, leaving
you will all kinds of unwanted spikes and slivers when you split or erase
objects.

The problem is that I, like many of you, use the Cosmetic Layer when
editing maps. In fact, when I first noticed the problem was going through
the prescribed method taught by MapInfo for fixing self-intersecting
polygon errors flagged by MapCheck. When I copied a string of nodes from my 
bounded map to the cosmetic layer, then transformed to a region and went
back to process this against my original, the region in the cosmetic layer
was slightly offset from the original.

This is because the Cosmetic Layer is unbounded -- you lose any increased
precision from your bounded objects when you paste them info the cosmetic
layer.

WORK-AROUND: If you work with bounded data, create a blank layer with the
same bounds clause and use it like you would your cosmetic layer when you
need to put/process objects in a temporary layer.

This certainly explains why I have so many unwanted artifacts in my maps...



Steve Wallace
GIS & Market Information Manager
Florida Farm Bureau Insurance Companies

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