Exercise
5b: Rubbersheeting data
About rubbersheeting
Rubbersheeting
is typically used to align two or more layers. This process moves the features
of a layer using a piecewise transformation that preserves straight lines.
This
exercise will show you how to rubber sheet data by using displacement links,
multiple displacement links, and identity links. You will rubber sheet a newly
imported set of street features to match an existing feature class of street
features.
Setting up the data and rubbersheeting options
Prerequisite:
Start
ArcMap and display the Editor, Snapping, and Spatial Adjustment toolbars.
Steps:
1. Click
the Open button on the Standard toolbar.
2.
Navigate to the Rubbersheet.mxd map
document located in the \Editing\SpatialAdjustment directory where you
installed the tutorial data. (C:\ArcGIS\ArcTutor is the default location.)
3. Click
the map and click Open.
4. If you
still have the map document open from the previous exercise and are prompted to
close it, you can do so without saving your changes.
5. Click
the Editor
menu on the Editor toolbar
and click Start Editing.
6. Close
the Create
Features window. You will not need it in this exercise.
Before
you start creating links, set your snapping environment so each link you add
snaps to the vertices or endpoints of features.
7. Ensure
vertex snapping is enabled. If it is not, click Vertex
Snapping on the Snapping
toolbar.
8. You
need to choose whether to adjust a selected set of features or all the features
in a layer.
Click the
Spatial Adjustment menu on
the Spatial
Adjustment toolbar and click Set Adjust Data.
9. Click All features in these layers.
10. Make sure only the ImportStreets layer is
checked. If necessary, uncheck the ExistingStreets layer. Click OK.
11. Click
the Spatial Adjustment menu,
point to Adjustment Methods, then
click Rubbersheet to set the adjustment method.
12. Click
the Spatial Adjustment menu and
click Options.
13. Click
the General
tab.
14. Click
Rubbersheet for the adjustment method so you
can set additional options for rubbersheeting.
15. Click
Options.
16. Click Natural Neighbor and click OK.
17. Click OK to close the Adjustment Properties dialog box.
Adding displacement links
Displacement links
define the source and destination coordinates for an adjustment. Displacement
links can be created manually or loaded from a link file.
In this exercise, you
will create your own displacement links at several key intersections of the ExistingStreets
and ImportStreets layers.
Steps:
1. Click Bookmarks and
click Import streets to set the current view to the area of this
exercise.
When the display refreshes, note that the
ImportStreets layer is not aligned with the
ExistingStreets layer. You must adjust the
ImportStreets layer so it aligns with the ExistingStreets
layer by using the rubbersheet adjustment
method.
2.
To get a better view of the adjustment area, zoom to the Intersections
bookmark, which was created for you. Click Bookmarks and
click Intersections.
3.
Click the New Displacement Link tool on the Spatial Adjustment toolbar.
4.
Snap the link to the source location in the ImportStreets layer, as shown
below:
5. Snap the link to
the destination location in the ExistingStreets layer, as shown below:
6. Continue to create
links at the perimeter intersections of the layers in a counterclockwise direction.
Look at the SnapTips to ensure you are snapping to the correct location. You
will create a total of six displacement links, as shown below:
Adding multiple displacement links
Steps:
1. To get a better
view of the adjustment area, zoom to the Curve features bookmark, which was created
for you. Click Bookmarks and
click Curve features. To preserve the curved road
features, you can add multiple links at critical points.
2. Click the Multiple Displacement Links tool on the Spatial Adjustment toolbar. The Multiple
Displacement Links tool allows you to create multiple displacement links in one
operation. This tool can help save time by allowing you to create more than one
link simultaneously; it is especially useful for curved features.
3. Click the curved
road feature in the ImportStreets layer.
4. Click the curved road feature in the ExistingStreets layer.
5. You will be
prompted to enter the number of links to create. Accept the default value (10)
and press ENTER.
The multiple links
now appear in the map.
6. Create multiple
links for the other curved feature.
7. Click the New Displacement Link tool on the Spatial Adjustment toolbar.
8. Add the final displacement links, as shown
below:
Adding identity links
Identity links are
used to anchor features at specific points to prevent their movement during an
adjustment.
You will now add
identity links at key intersections to maintain their locations.
Steps:
1. Click the New Identity Link tool on the Spatial Adjustment toolbar.
2. Zoom out and add five identity links at the
intersections as shown below:
Adjusting the data
Steps:
1. Click the Spatial Adjustment menu and click Adjustment Preview to examine the
adjustment.
The preview allows you to see an adjustment
prior to actually performing it. If the results of the adjustment are not
adequate, you can modify the links to improve the accuracy of the adjustment.
2. Click the Spatial Adjustment menu and click Adjust.
3. Here is how the
adjustment should appear:
Notice
that all the displacement links you created have turned into identity links.
The next step is to delete these links, since you no longer need them.
4. Click
the Edit menu and click Select All Elements. This
allows you to select the links, since they are graphic elements.
5. Press
the DELETE key.
6. Click
the Editor menu on the Editor toolbar
and click Stop Editing.
7. Click Yes to save your edits.
8. Close
ArcMap if you are done working with the tutorial. You do not need to save the
map document.
9. To continue
to the next exercise, Exercise
5c: Edgematching data.
In this
exercise, you learned how to set your data for an adjustment, create
displacement links, preview the adjustment, and adjust the data.
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