Map Arcs

In This Topic

Map arcs, a.k.a. parallels and meridians, are imaginary circles over the Earth's surface that lets the user see the map coordinates of a given location (latitude and longitude). Nevron Map for .NET supports rendering and labeling of parallels and meridians and gives you great control over their appearance and behavior. You can configure the rendering mode of parallels and meridians through the same name properties of the map importer class. They provide the following settings:

ArcRenderMode - determines the arc render mode and can be Hidden, Fine, Normal, Coarse and Fixed. When set to Hidden the map arcs will not be shown. The Fine, Normal and Coarse mode specify the density of map arcs and depend on the zoom level of the drawing view. The Fixed mode does not depend on the zoom level of the drawing view and always renders the arcs at the step specified by the Step property.
ZOrder - determines whether the map arcs should be rendered below or above map shapes.
LabelRenderMode - specifies the arc label render mode and can be Hidden, Visible and VisibleWithArcClipping. The last option produces nicest results, because it clips the map arcs so that do not cross the arc labels, but note that this mode may slow down rendering performance of your maps. If you favor performance over visual quality, set the LabelRenderMode to Visible.
StyleSheetName - determines the style sheet to use for these map arcs.
FormatString - gets/sets the arc label format string.

The following image shows a world map with map arcs rendered by Nevron Map for .NET:

During the map import process an NMapArcsShape is created for parallels and another one for meridians. You can use its properties to modify the rendering of map arcs and their labels without reimporting the map. To find a map arcs shape that contains a map arcs of a given type use the Find static method of the NMapArcsShape class. The map arcs shape provides the same properties as the map arcs settings, so you can use them the same way.

When you modify one or more of the map arcs shape properties do not forget to call the SmartRefreshAllViews method of the drawing document, so that all drawing views it is attached to get notified about the change and repaint themselves.