Mismatch between generated countours and areas

oreste.tommasioreste.tommasi Global Mapper UserPosts: 4
edited January 2012 in Bug Report
Generated contours and areas do not exactly match in any of the following two cases:
  1. some simplification is applied;
  2. 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

  • global_mapperglobal_mapper Administrator Posts: 17,238
    edited January 2012
    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
  • oreste.tommasioreste.tommasi Global Mapper User Posts: 4
    edited January 2012
    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...
  • global_mapperglobal_mapper Administrator Posts: 17,238
    edited January 2012
    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
  • oreste.tommasioreste.tommasi Global Mapper User Posts: 4
    edited January 2012
    No.
    The mismatch happens with smoothing turned on, OR with simplification != 0.
  • global_mapperglobal_mapper Administrator Posts: 17,238
    edited January 2012
    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
  • oreste.tommasioreste.tommasi Global Mapper User Posts: 4
    edited January 2012
    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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