Thanks Lars,
The worst accuracy is using a straight lat/long table, since it needs to accomodate 40000 km inside a 32 bit integer, resulting in a
coordinate accurracy/resolution of > 1 centimeter/? inch.
I always thought it was worse than that in an unprojected lat long, but that will be fine. Mind you, we may be worse off nearer the equator.
But I was really after some guideance if the accuracy of an object variable would be controlled by the system coordinates system or would it be just unprojected lat/ long as you suggest? In other words, Will I lose accuracy if I extract an object from a table, manipulate it as an object variable and insert it into another table, as compared to inserting that object from one table to another and manipulating it in the table. Will this be affected by the projection settings that I have for the system at the time?
The issue is that the way that I have developed a number of workarounds in a program to avoid system crashes that require pending object changes to be manipulated in memory, and I just realised that this may shift some of the nodes around slightly if the accuracy of objects in memory was different to that of the tables.
R
It's possible to control the bounds in a table, rendering higher accuracy, but I suspect the cosmetic "layers" to always use the
general lat/long projection, rendering them as the poorer choice.
So I'd go for a (temporary) table anytime if accuracy is a concern.
Best regards/Med venlig hilsen Lars V. Nielsen GisPro, Denmark http://www.gispro.dk/ ----- Original Message ----- From: "Robert Crossley" <[EMAIL PROTECTED]> To: "MapInfo List" <[EMAIL PROTECTED]> Sent: Thursday, November 25, 2004 7:33 AM Subject: MI-L Accuracy of an object variable?
Hi list,
While on a few occasions there has been some discussion on the accuracy of
putting an object into the cosmetic layer vs a table in terms of accuracy,
any comment on loss of accuracy taking an object from a table, processing
it as an object variable in memory and inserting it into another table
from the object variable?
r
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