Editing with auxiliary features (lines, points etc.) in Arcgis 9.3.1 - How?

Question

In order to digitize exact features in arcgis 9.3.1, our draftsman would like to use auxiliary features (lines and points mostly) that don't have to be saved later on. I told them the easiest way was to digitize the auxiliary features into a seperate shapefile - is there a simpler or better way?

(in case I didn't explain what I want very good I'll give an example. Suppose someone has to digitize a lighting post (point feature) 4 meters from a curb. In Autocad our draftsman would have digitized a line four meters long, using snapping he'd put a lighting post feature in the end of the line (in a different layer), and in the end he'd erase the line. Is there any way to mimck the process without actually digitizing into a shp/gdb?)

Thanks in advance.

Answer 1

Your Draftsman could use the Direction Distance Tool, that you find "under" the Sketch Tool button. The symbol on the button is a circle with a crossing line.

To use the tool:

Set your Target to you Lighting Post and then:

1. Set snap (edge/vertex) to your curb layer (Editor button -> Snapping).
2. Choose the Direction Distance Tool.
3. Click the position on the curb, where the lighting post should be placed.
4. Now a line shows up on the screen, and by moving the mouse the direction of the line can be changed.
5. When the right direction is represented by the line, the left mouse button is clicked.
6. Now click once more on the same place on the curb as in bullet 3.
7. Now a circle shows up on the screen.
8. Press "R" on the keyboard and state the radius of the circle (in other words how long you want the the post placed from the curb) - here 4 meters.
9. Press Enter on the keyboard.
10. Now choose which of the two possible intersections between the line and the circle you want to use.

That's it.

I know that the accuracy for the direction isn't that good, since you are unable to use the Perpendicular function, but maybe thats ok?

ArcGIS 10 has a new Place Point at the end of a Line tool, that will do exactly what you want, and you can use Perpendicular and so on too, but sadly it is not available in 9.3.1.

Hope this helps you.

Answer 2

We have several draftsman-turned-gis-techs who wanted this capability too, even after we showed them the various sketch tools in ArcMap. I created an Feature Dataset called Z_SKETCH and added a point and line featureclasss (Z_POINT, Z_LINE). The 'Z' doesn't have anything to with elevation, I just wanted it at the bottom of an A-Z sort.

This was a hurried solution and was the best option I could come up with for a versioned geodatabase (I needed something they could edit inside their versioned workspace). No one has ever experienced any conflicts (since it is mostly 'adds') and I'll occasionally purge the features in those featureclasses.

Answer 3

I use several approaches for this solution.

1. If it is new dataset and lots of drafting. I just do it in AutoCAD Map 3d, then export the shapefile. I use fdo to view file and personal gdb (via FME) and shapefiles or even sde data.
   I can set my document crs to whatever I want the output to be and I get ALL of AutoCAD's famous drafting tools. Very quick for lots of construction type drafting.

2. As described above using Arcmap 10, I create a line shapefile that I use the direction distance tool with. I create it in the same folder as my actual dataset so that I can edit both simultaneously.
   It is seperate from my actual data so I don't delete anything. I just re-use the same file anytime I am doing measured drafting.
   I prefer the new editing in 10 over the old 9.3. It is much more streamlined now and has some great features. (The template concept is nice to use for automating attributes.)
   The snapping still leaves a little to be desired at times but works much better than 9.3

3. If the dataset already has data and you need to do updates. It takes careful consideration as to the time constraints and then how much measured drafting there is to do.
   Ussually the more drafting that is needed constitutes using Map3d. However, I try more and more to use Arcmap.

I have also seen an addon drafting tools for arcmap, there is also a free arcgis for autocad.

I cannot do any GIS job without both tools, I have often said that having both tools in my holster and knowing when to use each is better than being stuck with either by themselves. They both have strenghts.

Answer 4

You can also press Ctrl + L to set the length when editing a line. You can also press Ctrl + A to set the length or To set the angle and length at the same time, choose the Direction/Length command from the Sketch tool shortcut menu or press Ctrl + G.

So you don't need to use auxiliary features to capture lighting posts 4m from the curb. Just set up the editing environment correctly.

http://webhelp.esri.com/arcgisdesktop/9.3/index.cfm?TopicName=Creating_segments_using_angles_and_lengths