For adding a point feature in the mode of coordinate editing the menu item Object+Add should be performed and point spatial category of the feature being added should be selected from the opened nested menu. A dialog box of adding a point feature shown at figure 17-3 will be opened.
Figure 17-3. Adding a point feature
To create a feature the user should fill in all the fields of the dialog box, such as:
Layer – the system offers to select a layer from all the layers of the browsed theme (that is, not necessarily all map layers).
Type – should be selected from all point feature types of the present theme layer.
Size – contains size of point feature symbol in map units.
Zoom threshold – is used for determining the maximal size of a symbol in the browser window when zooming. This parameter is specified in pixels (points) of the screen. Parameter Zoom threshold can take values from 1 to 1000.
The actual size of map symbol in pixels is determined by the parameter Size and the current displaying scale, but the size cannot exceed the value of parameter Zoom threshold. In this way it is possible to avoid the appearance of too big map symbols when zooming.
Slope angle – contains slope angle of the map symbol which is measured in degrees with respect to the horizontal coordinate axis. Positive rotation values determine counter-clockwise rotation, negative – clockwise rotation. The system transforms the entered slope angle value to the range from 0° to +360°.
Coordinates – contain values of coordinates X and Y which determine the position of the point feature on the map. When the feature is displayed the base point of its map symbol will be placed to the point with these coordinates.
Creation of a feature is completed after pushing the button OK. If the user left some fields empty or entered inadmissible values (for example, negative size) the corresponding message will appear and input focus will be placed in the input field containing an error.
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