How do I Import Existing Map Information?
Professionals often use digital mapping software called “geographic information systems” (GIS) to manage and analyze mapped data. These data, in the form of Shapefiles*, can be imported from other sources into Ortelius from Menu > File > Import Shapefile with some limitations.
Shapefiles are map data built and maintained by GIS professionals. Shapefiles provide vector map graphics and contain attribute information. For example, a Shapefile of a state with its counties may contain attribute information including the county names, population, and size of area. Ortelius map templates are created from Shapefile map data, consisting of the graphic map objects and the attribute information “behind the map.” Please note, Ortelius does not support georeferencing or re-projection, therefore manual registration is required to align more than one Shapefile.
A Shapefile is actually a collection of at least three files with ‘.shp” “.shx” and “.dbf” file extensions. All three files are required to actually use a basic Shapefile, and they must be identically named (except the file extension) and stored in the same folder/directory. The “.shp” file is the Shapefile that gets opened in Ortelius, the other files are referenced. A handful of other files may also be included, such as “.prj” for the projection information. Most GIS data providers will zip the Shapefile files for download.
Ortelius Standard Edition places the Shapefile as a set of separate graphical vector objects. To move and re-size the map layer, group the objects first.
With the new Shapefile layer active, choose Edit > Select All from the main menu. Next, choose Object > Group.
Move and Resize
Now the Shapefile objects can be moved into position and resized using the group’s object handles. To maintain the aspect ratio when re-sizing, be sure to hold the SHIFT key down on the keyboard.
As Shapefiles are imported as separate graphical vector objects in the Ortelius Standard Edition, use move and resize to manually position and align map features.
Once the map is in the desired position, ungroup the Shapefile to work with the object features, including adding styles and labels.
Repeat as Necessary
Use caution when adding more than one Shapefile. Ortelius Standard Edition places each new Shapefile as a set of graphical objects on their own layer in the map projection defined by the data provider. This means that even when resized and repositioned, the map layers still may not align correctly. This is not an error of the Ortelius software, rather it is based on the way the Shapefile data were provided.
Performance may suffer with large file sizes and is a limitation with the Ortelius Standard Edition. Turning on “Drawing Quality Modulation” in the Ortelius > Preferences menu substitutes bitmaps for vectors when rapid redrawing is needed, such as when scrolling, dragging and resizing, and may speed performance.
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