Vector Layer - Underwriters-Labs/renewables.openwind.help GitHub Wiki

Vector Layers include Point Layers, Line Layers, and Polygon Layers. They contain one or more geometry objects, and each geometry object has its own attributes. The attribute field names are the same for all the geometry objects within a vector layer while the attribute field values are specific to each geometry object.

The type for each field can be either character (C) or number (N) and can be changed by clicking in the type column and choosing from the drop-down menu.

The significance column allows the user to assign a field as one or both of the following:

• A label field, in which case values are displayed in the map-view as labels for each of the objects in the layer
• The select field, which means that, when browsing the layer, the values in that field are displayed in the bottom right of the Openwind interface in the status bar.

The index of the currently selected object is shown in the top right of the Attributes tab. The field values are those corresponding to the currently selected object. Changing the currently selected object will change the field values to that of the newly selected object.

Figure 1 shows the Attributes tab in the layer properties for all vector layers.

Figure 1: Vector Layer Properties: Attributes

The Graph button is there primarily to enable the display of specially generated GIS layers from applications such as UL’s Windnavigator.

Figure 2 and figure 3 show examples of the graphing functionality of Openwind. It is important to note that the data in each case are taken from the attributes of currently selected vector objects and that the particular fields used are determined by selecting the first and last attributes in the left-hand panel of the graphing window.

Figure 2: Openwind Graphing Interface Showing Speed for Each Hour in the Day

Figure 3: Graphing Interface Showing Directional Wind Frequencies

Going back to the Attributes tab, users may edit both the field names and their values. New fields can be added and existing fields deleted using the Add Field and Delete Field buttons, respectively.

The following several sections talk in more detail about specific types of vector layer.