Mismatch between generated countours and areas
oreste.tommasi
Global Mapper User
Generated contours and areas do not exactly match in any of the following two cases:
It seems that the simplification/smoothing is applied only on contours, not on areas.
This has been observed in GM12 and GM13.
Oreste
- some simplification is applied;
- smoothing is enabled.
It seems that the simplification/smoothing is applied only on contours, not on areas.
This has been observed in GM12 and GM13.
Oreste
Comments
-
Oreste,
This is possible since the smoothing is done on an area as a whole and that may be different since it will go down a side and wrap around. In general the simplification won't be affected by this, do you ever see the difference without the smoothing option enabled?
Thanks,
Mike
Global Mapper Guru
gmsupport@bluemarblegeo.com
http://www.globalmapper.com -
With simplification=0 and smoothing=OFF, I see no mismatch between contours and areas.
However, with smoothing off, contours can be very sharp; but smoothing cannot be enabled because the produced mismatch causes serious topological issues for us. Thus the result is not so satysfying... -
Unfortunately I don't have a good solution for applying the smoothing and getting areas and lines that stay coincident. Do they stay coincident with just the simplification applied?
Thanks,
Mike
Global Mapper Guru
gmsupport@bluemarblegeo.com
http://www.globalmapper.com -
No.
The mismatch happens with smoothing turned on, OR with simplification != 0. -
I will take a closer look and see if there is anything I can do, but I'm thinking there isn't too much that can easily be done.
Thanks,
Mike
Global Mapper Guru
gmsupport@bluemarblegeo.com
http://www.globalmapper.com -
Actually differences arise rather seldom, 99.5% of cases lines and areas correspond, sometime it is not easy to find a difference, but it is there.
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