Using Rulers in Annotation Objects

Many annotation objects utilize one or more rulers as part of the object.

The AnnPolyRulerObject class provides properties common to all rulers and are utilized by any class of annotation object that utilizes rulers. The following classes use rulers:

AnnPolyRulerObject

AnnCrossProductObject

AnnProtractorObject

Each of these classes (either through direct implementation or inheritance) access properties that control which aspects of the ruler are displayed and its unit of measure. The MeasurementUnit indicates the unit of measure for the ruler. For each possible value of the MeasurementUnit property there is a corresponding abbreviation for the unit of measure.

At each end of the ruler is a perpendicular line called a gauge. The length of the gauge is set or obtained through the GaugeLength property. The ShowGauge property indicates whether the gauges are displayed when the ruler is drawn. To display the gauges, set the ShowGauge property to true.

Along the length of the ruler are tick marks. The length of these tick marks can be set using the TickMarksLength property. To display the tick marks when the ruler is displayed, set the ShowTickMarks property to true. To display the length of the entire ruler, set the AnnObject.Labels["rulerlength"].isvisible property to true. The precision of the value displayed as the length of the ruler can be set using the Precision property. This property indicates how many digits to display to the right of the decimal point in the length.

AnnPolyRulerObject:

The AnnPolyRulerObject class derives from AnnObject and adds the properties mentioned above. The polyruler annotation object consists of an array of points that creates a sequence of joined rulers. This array of points is contained in the Points property, which is inherited from the AnnObject.

AnnCrossProductObject:

The AnnCrossProductObject class derives from AnnPolyRulerObject and adds the following:

AnnProtractorObject:

The AnnProtractorObject class derives from AnnPolyRulerObject and adds the following: