Digitizing fields using drawing and data editing tools

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The purpose of the Drawing tools in GeoAgro GIS, is to simplify the process of creating farm data as much as possible, making it more accessible for users with little GIS experience.

In these exercises, we are going to review a number of features for this purpose.


To access the drawing tools, first you need to click on the 'Edit Objects tool' Image:GIS_gis_Edit_05_01.jpg, and the drawing toolbar will display:

UDT14.jpg

Download sample data

For these exercises we are going to download a sample dataset: 'Sample Farm IA'

For this purpose, you can follow the steps detailed in Download sample data, selecting 'Sample Farm IA' as the initial dataset, which can be found under the 'Tutorials_en' folder:

UDT1.jpg



Exercise 01 – Drawing a field layout using drawing tools

The steps to use drawing tools are always the same:

  1. Make the layer where you are going to work active (see layer status)
  2. If you are going to work on an existing feature, select it using the Selection tools 
  3. Use the drawing tool of your choice.


In this example, we are going to assume that there are some Fields that were received from NRCS, in the 'Fields_NRCS' layer. Then we will copy them to the 'Fields_producer' layer, and add new fields to this layer.


Copy from layer 'Fields_NRCS' to layer 'Fields_Producer':


  1. Double click on the 'Fields_NRCS' layerImage:Layer_Fields_NRCS.jpg

  2. Select all features by using the Select all option Image:Select_All_2.3.21_01.PNG. All fields should be highlighted

  3. From the Drawing Tools, select the Copy Objects Tool Image:GIS_gis_Edit_05d_01.jpg

  4. Select Fields_producer as the target layer, and click on Copy:
    UDT4.jpg//UDT4


Digitize a new field

  1. Double click on the 'Fields_producer' layer, where we are going to add fieldsImage:Layer_Fields_Producer.jpg

  2. Use the Snap option on the upper left corner → set the snap to 'Fields_Producer'. UDT2.jpg 
    That way we'll make sure that when you digitize, the cursor will snap to the closest node in this layer. This assures that fields are properly digitized (avoiding slivers, or overlaps with other fields)

  3. Select the  Image:GIS_gis_Edit_05a_01.jpg Add New Object tool to digitize a new field. This article: Add New Object describes this tool, and this article: Edit_object shows how nodes are  added/modified/deleted while you digitize. Start adding nodes and digitize the field as shown in the figures. Finish with a double click in the last node, or after placing the last node, do a right-click.
UDT5.jpg UDT6.jpg


Divide the digitized field to divide it in 3 fields

We are now going to divide the recently created field in three fields

  1. Make sure that the field to be divided is selected as in the figure. If not, click on 'Fields_producer' to make it active, then use a Selection tool to select it.\Click to see full size image



  2. use theDivide Objects (Line) tool Image:GIS_gis_Edit_05k_01.jpg  to create the field in the upper right corner as shown in the figure below. Start the line outside the field, and click outside the field to complete the cut. Finish with a double click or right-click after you placed the last node
    UDT8.jpg


  3. Do the same operation to create a second field, as shown in the figure below.
    UDT9.jpg


  4. Now, let's digitize an area that will not be cultivated, by using the Divide Objects (Polygon) tool Image:GIS_gis_Edit_05l_01.jpg :
  5. Select the field that will be cut.
  6. Zoom to the area where we'll cut the polygon .
  7. select the Divide Objects (Polygon) tool Image:GIS_gis_Edit_05l_01.jpg
  8. start digitizing, double click to finish
    Click to see full size image

  9. Double click on the 'Fields_Producer layer', your fields should look like this:
    Click to see full size image

'Other useful tools when drawing/editing'

There are other useful drawing tools, in addition to the previously used in exercises above. You may want to review and test them in a sample area, to see the different possibilites.


Exercise 02 – Entering attribute data


We will now enter attribute data into the fields that we just created

The steps to enter attribute data are always the same:

  1. Make the layer where you are going to work active (see layer status)
  2. Select the feature in which you will add/modify attribute data using theSelection tools 
  3. Click on the Edit object's data Tool Image:GIS_gis_Edit_06_2.3.13_01.jpg to start entering attributes


In our example, we are going to enter land unit numbers and crops in each field

  1. Double click on the 'Fields_Producer' layer Image:Layer_Fields_Producer.jpg
  2. Select all features by using the Select all option Image:Select_All_2.3.21_01.PNG. All fields should be highlighted.
    If you would like to exclude a couple of fields that will not be 'attributed', you can do so by using the Select Point option, and then select the excluded fields while holding the Ctrl key.

    Click to see full size


  3. Click on the Edit object's data Tool Image:GIS_gis_Edit_06_2.3.13_01.jpg   which will open the attribute table.

  4. Please note that when you click on each record in the table, the feature in the map is highlighted You can move and resize the data entry table to see both the map features and records 
    Click to see full screen

  5. Enter the values shown in the map below, numbers in the 'Field Name' column, and type of crops in the 'Crop' Column:
    UDT15.jpg