1. Physical Structure of GDB
Geodatabase
Feature datasets
Spatial Reference
Object classes, subtypes
Features classes, subtypes
Raster datasets
Rasters
Relationship classes
Geometric networks
TIN datasets
nodes, edges, faces
Planar topologies
Locators
Domains
Addresses, X.Y location
ZIP Codes, Place names
Validation rules
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2. Topology and Annotation
Geography
KHU Jinmu Choi
Topology (4)
Map Topology (3)
Geometry with Topology (5)
Annotation Class (4)
Annotation Types (3)
Creating Annotation Class (8)
Summary, Reviews, and Next…
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3. When do you need Topology?
When editing coincident features, to maintain the spatial relationships that exist among them
For example, when you edit the shared boundary between two land use features, remove a gap
To prevent editing errors
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4. Purpose of a Topology
The primary purpose of a topology is to define spatial relationships between features
The primary spatial relationships that you can model using topology are adjacency, coincidence, and connectivity
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5. Topological Spatial Relationship
Adjacency: to identify which land owners or soil types share a common boundary with each other
Coincidence: to identify the bus routes on top of roads
Connectivity: to follow a path from the water treatment plant to a house or the flow of water through streams
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6. Topology Types
There are three types of topology available in a geodatabase:
Map topology
Geodatabase topology
Topology in a geometric network
The three types of topology are all similar in that the spatial relationships are based on coincident geometry
They differ in how they are created and maintained
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7. Creating Map Topology A map topology is created during an edit session
You specify which feature classes in a single geodatabase you want to include and, if necessary, change the cluster tolerance
The cluster tolerance: how close together features must be in order to be considered coincident
The default cluster tolerance: minimum possible cluster tolerance based on the precision of your data
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8. Creating Map Topology
Once you have created the map topology, spatial relationships are discovered on the fly for the current map extent
The geometric relationships in a topology are between the parts of the features rather than the features themselves
When you edit features in a topology, the types of geometry that are acted on are edges, nodes, and pseudo-nodes
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9. Working with Map Topology
Example
The shared border between the countries of Chad and Sudan is treated as one element (an edge) in a topology
The point where the borders of Chad, Sudan, and Libya come together is also a single element (a node) in a topology
Map topology is
only effective
during an edit
session
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10. Geometries with Topology
Line and polygon topology consists of features with coincident segments
Each feature stores all of the coordinates for itself; the geometry for the coincident segments is stored twice in the GDB
Point features behave as nodes when they're coincident with other features (stored for each)
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11. Editing with Topology
After you create a map topology, you have access to all of the topology editing tools in ArcMap (View/Toolbar/Topology)
With these tools, to create and maintain coincidence between parts of features
Your starting point is the Topology Edit tool
After you select an edge or node with this tool, all other topology editing functionality becomes available
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12. Editing Nodes and Edges
Using the Topology Edit tool, you can modify coincident geometry for two or more features simultaneously
Move an edge or node
The Topology Edit tool is used to select and drag a node to a new location. The connected edges rubberband to maintain coincidence
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13. Editing Nodes and Edges
Reshape an edge
With the Reshape Edge task selected, the Topology Edit tool ( )is used to select the edge and the Sketch tool is used to reshape it
Modify an edge
With the Modify Edge task selected, the Topology Edit tool is used to select the edge, add a vertex using a context menu, and move the vertex
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14. Editing Nodes and Edges
Auto-Complete Polygon
Click the Task drop-down list and click Auto-Complete Polygons.
Click the target and click the polygon feature class to which you want to add polygons.
Click the Sketch tool .
Start an edit sketch.
Starting from the boundary of an existing polygon, use the Sketch tool to digitize a boundary of the new polygon that will share a boundary with the existing polygon.
Right-click anywhere on the map and click Finish Sketch.
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15. Show Shared Feature tool
Which features share a selected edge or node?
Use the Topology Edit tool and the Show Shared Features tool to find out
To temporarily remove an element from the topology if you don't want your edits to affect it
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16. Why Annotation!
The goal of map creation is to effectively communicate info. to the intended audience
Adding descriptive text to the map can help you
Feature labels can be added using ArcMap's dynamic labeling tool
Creating annotation gives you greater flexibility
Unlike dynamic feature labels, you can reposition annotation as needed
With annotation, the text string, position, and display properties are all stored together and can be individually edited
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17. Storing Annotation Annotation can be stored two different ways
you can store it as graphic elements in a map doc.
You can store it as an annotation class in a geodatabase annotation feature class
Annotation class in a annotation feature class can be used over and over again in any map document
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18. Annotation Class
Annotation feature classes are similar to other geodatabase feature classes
Like other feature classes, annotation feature classes
have attributes and a spatial reference (polygon)
Annotation attributes define
how the text is to be displayed
Added as a layer to ArcMap
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19. Multiple Annotation Classes
All annotation feature classes have at least one annotation class
An annotation class has a set of properties such as text symbology and alignment
Multiple annotation classes within one annotation feature class (With ArcEditor or ArcInfo license)
World Water Bodies is an annotation feature class that has three annotation classes
In ArcMap, annotation classes display in the Table of Contents
Each class can be turned on or off individually
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20. Annotation Types There are three types of geodatabase annotation:
Standard (or simple) annotation
Feature-linked annotation
Dimension annotation
To create and edit feature-linked and dimension annotation, an ArcEditor or ArcInfo license is needed
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21. Standard Annotation
Standard annotation feature classes exist independently of other feature classes
No permanent relationship exists between the annotation and the features they describe
Advantages of Standard annotation
To create annotation for the state of a database at different times/conditions
The land use for parcels over a period of years
To label areas on your map where features don't exist in your database
Label the oceans without ocean features in DB
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22. Feature-linked Annotation
Feature-linked annotation is associated with features in another feature class
A composite relationship
When you move the geographic features, annotation moves with them
If you delete a feature,
its annotation is
automatically removed
If you change the feature attribute used to create
the annotation, the annotation
text changes as well
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23. Creating Annotation In ArcMap: convert label to annotation
In ArcCatalog: to create empty annotation class
To populate standard annotation feature class
Convert label to annotation
Manually add annotation using Annotation toolbar
To populate feature-linked annotation feature class
Use feature property, create new link between annotation class and feature attribute
Use Select/Annotate Selected Features command
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24. Populate Feature-link Annotation
Which features in the linked feature class will be annotated by the empty annotation class
How the annotation text strings will be defined based on attributes in the linked feature class
How to place new annotation
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25. Empty Standard Annotation
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26. Empty Standard Annotation
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27. Empty F-linked Annotation
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28. Empty F-linked Annotation
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29. Link Annotation to Attribute
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30. Dimension Annotation Dimensions are a special kind of annotation
To display specific lengths or distances on a map
They are stored as features in dimension feature classes
Dimension features are
used to show
the distances between
electric power poles
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31. Summary Map Topology Creating Map Topology Annotation
Graphics or Annotation Feature Class
Annotation Class Types
Standard or Feature-linked Annotation class
Creating Standard Annotation
Creating Feature-linked Annotation
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32. Next… Lab. Creating and Editing topology and Annotation in Geodatabase
Modeling with Networks
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