IV-4 Feature Control Page
The Feature Control page defines feature display and selection for the map in use with the SICOM Display Module. Feature display may be either By Feature or By Layer. Layers are defined on this page. Feature code lists on this page are determined from the file pointed to by the SICOM environment variable - SICOM_FEATURE_LIST. This file may have been created by the Feature Lister application and is a text file (.txt) consisting of the feature codes, one per line, for the map being used. If there is no SICOM_FEATURE_LIST environment variable then the default is a file named allFeatureCodes.txt in the current directory.
If By Feature is selected then the Working and Overview list boxes will contain the list of available features. Features need to be highlighted to be selected for display in the working map view(s) and in the overview (if used). Simply click on a feature in the list box to toggle the feature as either selected or not. To select multiple features, hold down the control key and click on each desired feature. To select a range of features, click on the first feature in the range, press and hold the Shift key, then click on the final feature in the range. Only the highlighted features are selected and will be displayed in the SICOM Display Module.
Fig. IV-4.1 Feature Control Page
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he features displayed on this page are taken from the file to which the SICOM_FEATURE_LIST environment variable points. If you load an existing profile containing a different list of feature codes than the to which SICOM_FEATURE_LIST points, then the features will not be displayed. Any feature codes that are common to both the loaded Profile file and the set feature file list, and that were selected in the loaded Profile file, will be displayed as selected. Should this situation occur and you wish to avoid over-writing previous feature selections loaded in the Profile, click Cancel and none of the changes made to the Profile will be saved. Alternatively, you may click Exit and save the Profile file under a different name/directory.If By Layer is selected then layers of feature codes may be defined. To define a layer, enter the layer name in the box beneath Define Layer and click the Add Layer button. The new layer should appear in the display box to the right. To add features to a layer, select the layer in the display box so that the layer name is highlighted; then select a feature from the drop-down box below Feature Codes and click the Add Feature button. The feature should appear as a branch of the selected layer in the display box. Multiple features may be added to a layer. Multiple layers may be added. The same feature can be part of more than one layer. Using layers instead of features allows entire layers to be selected for visibility in the Working and Overview boxes.
Fig. IV-4.2 Layer Definitions and Options
Layers and features may be removed from the layer selection by highlighting the layer or feature and clicking the Remove Layer/Feature button.
Selecting Auto Build Complement creates a layer named Complement that contains all the features that have not been selected for any defined layer.
The User Can Alter option permits the SICOM Display Module user to alter the layer settings when they run the Display Module.
Toggling between By Layer and By Feature will remove any of the layer and feature display settings.
The Alter Default option for the Working and Overview display allows the SICOM Display Module user to alter the defaults defined on this page. Alter Current allows the user to change the values only during the current run of the Display Module.
The Feature Selection control options define how features may be selected in the SICOM Display Module. By Click allows feature selection by pointing the mouse at the feature and clicking the mouse button. By Rectangle allows feature selection within a rectangle, and is executed in the SICOM Display Module by clicking the mouse at the upper left hand corner, and, with the mouse button held down, dragging until the desired rectangle is.
The Backdrop option is currently disabled.
The Feature Addition option determines if it will be possible for the user to add features in the SICOM Display Module. Selecting Add Features permits the user to add new transient features. Selecting the Allows Persistence option permits the user to add new permanent features.