The Route Map screen consists of the primary window displaying a map of the continental U.S. and a legend area on the left hand portion of the screen. Four coverages are shown in the legend—Railnode, Raillink, Indian, and States. The Railnode coverage consists of points representing each node in the rail network database. The rail network is shown as one coverage, called Raillink. As with the highway transportation mode, the Indian and State coverages show Native American tribal lands and the state boundaries. All four coverages are initially displayed on the screen. By clicking on the check box, the check mark can be removed, which caused the display to be redrawn without that coverage shown on the map.
Fig. 4.20. Example of a rail route with a railroad company blocked. 4.8.2 Using MapTips
In the lower right center of the screen, MapTips has been checked, as shown in Fig. 4.21. (The MapTips item is checked for this example to assist the discussion of this feature. By default, MapTips is not checked when the Route Map screen is displayed.) Two pull down boxes appear to the right of the MapTips label. The left pull down box is used to select the coverage, in this case the Railnode coverage. The right pull down box is used to select an individual attribute of coverage. With the Railnode coverage is selected, the attribute field defaults to Name. Zooming into a specific area best uses the MapTips feature. Move the pointing device over a node and the name of the node will be shown on the screen. MapTips can be used to examine the attributes for any of the coverages shown on the Route Map screen. 4.8.3 Displaying Routes
WebTRAGIS provides two methods of displaying a calculated route in the Route Map screen. The first is a simple and fast method that draws a stick figure representation of the route. The second takes more time, but displays the complete shape of the route. Figure 4.22 provides an example of the difference between the two methods. The route shown in this figure is the NS line passing northeast of the Great Smoky Mountains along the North Carolina-Tennessee border. The green segments show the route representation using the stick figure method and the blue line is the shape file method. The red circles show the rail network nodes.
Fig. 4.21. Rail route map screen. 4.8.3.1 Stick figure routes
The simplest method draws straight-line segments between nodes. This technique is very fast and is sufficient for first draft national scale maps. The top row of buttons on the upper right hand portion of the Route Map screen is used to control the drawing of routes with this method. The Show Route button will display the most recently calculated route. (Even if you have just started WebTRAGIS, the most recently calculated route means the last route you have created with the model.) If you are creating a series of routes, the Show Route button can be pressed after the calculation of each to display multiple routes on the screen. Each successive route is displayed in a different color on the screen. The Save Route button saves all the routes displayed on the screen in one file in the ESRI shape file format. When this button is pressed, a save as window is opened to allow the user to select the folder the file is stored. The Clear Routes button will clear all routes displayed on the screen.
4.8.3.2 Shape file routes
The Generate Shape File button provides the capability to make a map of the route showing the full detail of the geographic shape available with the 1:100,000-scale rail network available in WebTRAGIS. This process is slightly more complicated compared to the method described in the previous section, but is the preferred method if large scale (showing small areas) maps are needed. When the Generate Shape File button is pressed a Save As window is opened, which provides the method for a unique file name to be entered. The file is saved in the ESRI shape file format, which can be used with ESRI GIS software,
such as ArcView and ArcGIS. After entering the file name, press the Save button. After a brief delay, the shape file will be created, displayed on the map, and an entry will be added to the legend. Click on the name of this new coverage to change the attributes, such as color and line width, of the route. To remove a generated shape file from the Route Map screen, select the coverage (click on the coverage legend so it appears to be slightly raised or highlighted) and then press the Remove Active Map Layer button, which is on the button bar (see Sect. 6.1.9).
Fig. 4.22. Difference between the two rail route representations.
Previously saved routes or other shape files can be added to the WebTRAGIS map display. Further information on this capability and other mapping features of WebTRAGIS is discussed in Sect. 6 of the user’s manual.