How to buffer a polyline without overlap at verticies

19284
22
03-09-2014 07:36 PM
JimPace
New Contributor
I have polyline tracks that I split at each vertex and then calculate attributes for each segment.  I then need to generate a buffer of each segment that keeps those attributes but not have any gaps or overlap at the ends (both flat end and round end do this).  I've played with this a long time and can't figure it out.  I'm trying to do something like the attached picture.  Any suggestions?

[ATTACH=CONFIG]32063[/ATTACH]
0 Kudos
22 Replies
GajBala
New Contributor II

I figured it out..I was using decimal degrees when I should have been using meters.

I am going to back trace a bit here...So my goal is to cut road polygons that I have (See Image).

I want to cut these polygons very similar to yours (See Image)

So at every intersection cut them into triangles. So my question is did you have a centerline that you started from? Which you then buffered?

In my case I have the polygons and I created the centerlines using Vectorization. Will these steps work for me?

How may I access your tool that you are working on?

Thanks

0 Kudos
RichardFairhurst
MVP Honored Contributor

Glad you figured out the issue for the coordinates.

I did base my process on a Centerline layer I had.  The centerlines determine the angles to use for the intersection cuts.

I have not yet placed my tool in a location where it can be accessed by others.  The interest in it seems to be growing, so I will try to find some time to develop an interface this week so it can be released for testing.  The tool used my centerline layer to create the left and right buffer polygons I showed in the picture in post 4 of this thread.

The intention is to create idealized and over-bounded buffers that contained the centerline data and intersect those buffers with the actual road casements based on parcels or aerials.  Alternatively,, with an advanced license the intersections X and Y cuts can be extracted using the Polygon to Line tool and retain only the lines that do not have -1 for the left side (the sides of roads would all have -1 for the left FID).

Below is an image of my parcel road casements on top of a 50 foot buffer surrounding my centerlines.  Where you see solid red fill and black outlines the buffer over-bounds the casement.  Intersecting the road casement polygons with the buffers would cut them at the X and Y cuts that are ghosted inside the intersections.  Only cul-de-sac bulbs create a special case that my tool does not deal with.  The test shown below took 2 minutes and 18 seconds to create the left and right buffers for over 5,000 centerlines (over 10,000 buffers).

Road_Casements.png

One of the potential enhancements I may consider in the future is to vary the buffer width based on a field value for each centerline so that I could do different buffers according to the road classifications.

0 Kudos
GajBala
New Contributor II

That is good to know that you are almost done. Is there a way to get in touch with you via email? because I am very much interested in the tool. Please let me know.

Thanks

0 Kudos
RichardFairhurst
MVP Honored Contributor

Here's a link on how to send a message in here. Messages

Thanks to Lisa Turner who posted this on another related thread.

0 Kudos
xiaoyunwu
New Contributor II

Hi Richard,

Is it possible for me to also get an access to the tool that you are developing?

I read the thread and the kind of buffer with the triangular end (instead of overlapping) is exactly what I need.

Please let me know if this is okay with you.

Thank you,

Sherri

0 Kudos
RichardFairhurst
MVP Honored Contributor

I got sidetracked with other work and have not finished the interface.  Anyway, I will see if I can get it moved back to the front burner.

0 Kudos
xiaoyunwu
New Contributor II

If you could let me know when you finished, that would be great!

Thanks!

BrendanMcCarthy
New Contributor

Could you add me on to the list of people interested in getting this in a tool or script?  I attempted to perform this process myself, but must have done something wrong.  I will try again, but just thought I would check and see if you have had any luck on the automation front.  Thank you!

0 Kudos
RichardFairhurst
MVP Honored Contributor

Brendan:

I had good intentions to get this out last year, but ran into some issues that I was not sure how to resolve and then work and life got in the way of going beyond a tool for my personal use.  For example, it seems that the VB.Net addin I developed needs to register one of its files on secure networks.  This was not a problem on the system where I developed the tool, but presents a problem for distribution to end users in a work environment.  I may try tackling this again, but the gotchas that come up when a tool moves beyond a specific controlled implementation and gets developed for broad distribution are challenging.

0 Kudos
BrendanMcCarthy
New Contributor

That makes sense.  I will give it another go with the instructions above and see if I can't get it to work.  Thank you for your time and the response.

0 Kudos