topic Re: snapping polygon to line in Mapping Questions

snapping polygon to line

SherryMcGartland — Thu, 12 May 2011 16:32:18 GMT

I'm looking for a way to automate a process where a parcel polygon will automatically snap to an adjacent road midline. I've done something similar with z values, but haven't been able to find a tool to do this in 2D. Any suggestions?

Re: snapping polygon to line

JeffBarrette — Fri, 13 May 2011 13:50:22 GMT

You may want to try posting this to the Editing forum.

http://forums.arcgis.com/forums/116-Editing

Jeff

Re: snapping polygon to line

SherryMcGartland — Mon, 16 May 2011 10:52:43 GMT

Jeff,
Thank you for your response. There are several ways to achieve the required results through editing, however I'm looking for an automated way to perform the task.
Sherry

Re: snapping polygon to line

DanLee — Wed, 22 Jun 2011 17:25:38 GMT

Hi Sherry,

This may not be an easy process to fully automate. You might have a spatial adjustment or conflation problem to solve. We are working on some automation of these processes. Do you mind sharing a small sample data of the parcels and road midlines/centerlines with me (you can attach a zip file to email: dlee@esri.com)?

Thanks.

Re: snapping polygon to line

SherryMcGartland — Thu, 30 Jun 2011 16:18:01 GMT

Hi Dan,

Thanks for responding. I appreciate any help I can get with this. There is no midline in the process, that was a workaround using topology editing tools, we can still create if necessary but my preference would be not to have to. I've attached a sample of the parcels, the white area in between is the road, we need to eliminate any white area and extend the parcels out to the middle of the road or white area. This is a tedious time consuming task right now that is being performed several times per day.

Thanks,

Sherry

Re: snapping polygon to line

DanLee — Thu, 30 Jun 2011 17:35:36 GMT

Well, you can try the following (requiring ArcGIS 10 and ArcInfo license) - use your sample data to test first:
(Step 4 below modify the parcels; so make sure you have a backup copy of the parcels)
1. Run Feature To Line tool to convert parcel polygons to lines (lines are required for the next step).
2. Run Collaspe Dual Lines To Centerline with max_width = 30 (worked well for your sample data)
3. Select LnType = 1 of the centerlines
4. Run Snap tool (Editing toolbox) to snap parcel polygons to the selected centerlines using the EDGE option and Distance = 20 meters for example.

You will need to inspect areas where centerlines end (at large intersections or open areas) and the parcels on both sides are "uneven", e.g. poly 3 and poly 33 in your sample data. Manual editing would be necessary.

Depending on how complex your entire parcel data is; you may need to inspect or edit the centerlines before snapping.

Hope this is helpful to some degree.

Thanks.