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Auto-trace layers

  • 1.  Auto-trace layers

    Posted 01-13-2020 05:23
    Edited by Richard Sherman 01-14-2020 11:27
    ​Dear All,

    I need to insert a new polygon into an existing workspace. I have selected the layer - made editable - put Auto - Trace and Snap on. This allows me to select one side of the layer to auto trace but how do I select the other boundary of this new polygon? As this boundary is located on another layer -

    Edit: I managed to resolve this issue using Spatial - Set Target and Erase outside target area




    Thanks


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    Richard Sherman
    Knowledge Community Shared Account
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    ​​


  • 2.  RE: Auto-trace layers

    Posted 01-13-2020 05:37
    ​Yep, you can only trace objects in the same layer.
    2 stages for the 2 halves and then combine those into one polygon.

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    John Ievers
    CDR Group
    Hope Valley, United Kingdom
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  • 3.  RE: Auto-trace layers

    Posted 01-13-2020 05:46
    If you need to trace two individual objects to create a new object, you will have to trace them individually.

    Start by snapping to a node in the first object, now trace this object until the intersection where you need to trace the second object. Here you have to make sure that you have snapped to a node in the second object before you can trace this object.

    But maybe I'm misunderstanding your request?

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    Peter Horsbøll Møller
    Distinguished Engineer
    Pitney Bowes Software & Data
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  • 4.  RE: Auto-trace layers

    Posted 01-13-2020 10:44
    ​Hi - thanks for your replies - I see - yes I want to split this existing area into two sections - the top half as one polygon and the bottom half as the other polygon but I am not sure the best way of going about it. If I auto-trace I cannot overlap each end to create the polygon. Also I have tried using the 'Set Target' Under Spatial - but I cannot make the original layer editable to be able to do this.

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    Richard Sherman
    Knowledge Community Shared Account
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  • 5.  RE: Auto-trace layers

    Posted 01-13-2020 11:52
    You've lost me now Richard!
    I thought you were trying to create a new polygon of the blue outline from 2 underlying boundaries in 2 separate layers.
    Please clarify...

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    John Ievers
    CDR Group
    Hope Valley, United Kingdom
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  • 6.  RE: Auto-trace layers

    Posted 01-14-2020 04:35
    Edited by Richard Sherman 01-14-2020 04:36
    ​Hi John,

    Thanks for your reply - sorry it is quite confusing - what it was - I already had an existing polygon layer with the blue boundary - then I wanted to split this polygon into two sections (separate polygons) along the middle boundary line splitting the light and darker purple sections.... so originally I tried to auto-trace but I could only auto trace one half of each side of the existing polygon.

    Therefore I used this method instead which is using the Spatial menu then by using Set Target and Then Erase Target, Outside Area. This enabled me to create the two separate layers which I saved off separately then went back and added these to my original workspace.

    Thanks

    Richard

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    Richard Sherman

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  • 7.  RE: Auto-trace layers

    Posted 01-14-2020 10:15
    Hi Richard,

    Reading through what you are trying to do, I would select the polygon and append it to the layer you need. Then using the Split Region using Polyline, cut the area into the halves that you need.

    This should hopefully give the results you are looking for.

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    James King
    Essex County Council
    Chelmsford
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