topic Re: erase tool while heads up digitizing in Data Management Questions

erase tool while heads up digitizing

JeremyOlynik1 — Thu, 12 Nov 2015 16:08:37 GMT

Hello,

I'm wondering if anyone knows of a third party tool or something built into ArcGIS 10x that will erase or clip an area of a polygon quickly and efficiently. I'm thinking something like the 'magic eraser tool' in Photoshop. I'm trying to manually digitize sand within reef communities and as it stands I'm digitizing a polygon over-top of the the wider 'reef' polygon and then clipping the underlying data... all the while thinking that there has to be a better way of doing it as there are many areas. These are areas where image classification isn't working out well.

Any thoughts are appreciated thank you.

Re: erase tool while heads up digitizing

MitchHolley1 — Thu, 12 Nov 2015 16:39:02 GMT

Have you tried the Erase (Anaylsis) tool ArcGIS Help 10.1- Erase

It's in the 'Analysis Tools' -->'Overlay' toolbox

Re: erase tool while heads up digitizing

ChrisSmith7 — Thu, 12 Nov 2015 16:45:02 GMT

Not sure if this helps you at all, but check out the polygon editing tools of ET Geo Tools:

The concept of Polygon editing

ET GeoTools User Guide

There are some tools that will make your polygon editing work flow a bit easier...

Re: erase tool while heads up digitizing

JeremyOlynik1 — Thu, 12 Nov 2015 17:14:21 GMT

Thanks for the reply Mitch. I don't have the two layers separated as yet but if I did then I would use the erase tool for that for sure. Here is an example of what I'm trying to separate.

Re: erase tool while heads up digitizing

JeremyOlynik1 — Thu, 12 Nov 2015 17:17:30 GMT

Thanks Chris. It looks like the polygon editing tool isn't available in the free version of ET GeoTools. Also, I tried using it and it looks like there is no 'streaming vertices' available when editing so it would be difficult to digitize multiple polygons. I do use ET GeoWizards often and can recommend that as well for geoprocessing.

Re: erase tool while heads up digitizing

KyleBalke__GISP — Thu, 12 Nov 2015 17:47:48 GMT

Jeremy,

Not sure exactly if it fits your need but ArcMap does have the ability to do an interactive clip while editing.

Start your editing session
Select the features you want to clip out of your polygon
Slick the Editor button on the Edit tool bar
Select Clip from the list
Choose Discard the area that intersects on the Clip dialog

And then the result

Re: erase tool while heads up digitizing

MitchHolley1 — Thu, 12 Nov 2015 17:50:03 GMT

Jeremy,

Try using the 'Extract by Mask' (Spatial Analyst) tool. ArcGIS Help 10.1- Extract by Mask

If that red line is a feature class. This tool will work perfectly

Re: erase tool while heads up digitizing

JeremyOlynik1 — Thu, 12 Nov 2015 17:55:30 GMT

Thanks Kyle - yeah, that's what I've been doing thus far. I'm creating a new polygon using streaming vertices and then using the clip function on the editor toolbar. It does work although I was hoping to avoid the need to 'clip' the background polygon somehow to speed up the process. If there was some kind of 'eraser' of the background polygon using a brush of a certain width, I think that would be ideal. It is possible that it just doesn't exist!

Re: erase tool while heads up digitizing

JeremyOlynik1 — Thu, 12 Nov 2015 17:59:46 GMT

Sorry for not being clear, I'm trying to separate that sand that is within that polygon from the small fingers of coral that surround them. The extract by mask tool would work if I was clipping a raster but i'm trying to create a sand/reef polygon based on the imagery. It may be that I have to continue trying to classify it although I don't have access to the high resolution imagery as it is coming off an image server and the size is very difficult to work with when exported.

Re: erase tool while heads up digitizing

KyleBalke__GISP — Thu, 12 Nov 2015 18:04:07 GMT

It doesn't exist (as far as I know) if you are working with vector data...just goes against the structure of the data model. There is a Raster Painting option in ArcMap that you might take a look at and see if you can use it in conjunction with the output of an image classification.

I feel your pain...I have digitized large forested areas for several custom maps I have created in the past.

Re: erase tool while heads up digitizing

MitchHolley1 — Thu, 12 Nov 2015 18:04:21 GMT

So, you're needing to digitize polygons around a certain area? I don't think there is a tool that can do that considering how specific the polygons need to be.

Re: erase tool while heads up digitizing

JeremyOlynik1 — Thu, 12 Nov 2015 20:10:05 GMT

Yeah, that makes sense. I think even if there was a script tied to a new polygon where it took priority over everything behind it and automatically clipped the underlying polygon. This way I wouldn't have to select clip every time.

Re: erase tool while heads up digitizing

JenniferMcCall4 — Fri, 13 Nov 2015 12:23:27 GMT

Have you considered using the Cut Polygons tool on the editor toolbar to digitize the areas you want to erase?

Re: erase tool while heads up digitizing

DanPatterson_Retired — Fri, 13 Nov 2015 13:38:36 GMT

Make a donut and dump the hole as has been suggested earlier