Marker Attributes

Markers are drawn when a Data node is rendered with its DataType attribute having its DATA_TYPE_MARKER bit set. Drawing of markers is affected by the attributes described in this section. Note that even though some markers are drawn using lines, the line attributes do not apply to markers.

An alternative to markers are images, which can be used to draw arbitrary symbols instead of markers.

Attribute MarkerType

MarkerType is an integer-valued attribute that determines which marker will be drawn. There are constants defined in ChartNode for the marker types. IMSL charting is largely made up of classes that inherit from ChartNode. Therefore ChartNode.MarkerType should be used to set the line dash pattern. The default value is MARKER_TYPE_PLUS. The following are all of the defined marker types. For clarity, these are drawn larger than normal.

Attribute MarkerColor

MarkerColor is a Color-valued attribute that determines the color of the marker. Its default value is Color.Black. IMSL charting is largely made up of classes that inherit from ChartNode. Therefore AbstractChartNode.MarkerColor should be used to set the marker color.

Attribute MarkerSize

MarkerSize is a double-valued attribute that determines the size of the marker. IMSL charting is largely made up of classes that inherit from ChartNode. Therefore AbstractChartNode.MarkerSize should be used to set the marker size. Its default value is 1.0. The actual size of the drawn marker, in pixels, is 0.007*MarkerSize*width, where width is the width of the Control containing the chart.

Attribute MarkerThickness

MarkerThickness is a double-valued attribute that determines the thickness of the lines used to draw the marker. Its default value is 1.0. IMSL charting is largely made up of classes that inherit from ChartNode. Therefore ChartNode.MarkerThickness should be used to set the marker thickness.

Attribute MarkerDashPattern

MarkerDashPattern is a double-array-valued attribute that determines the line pattern used to draw the marker. IMSL charting is largely made up of classes that inherit from ChartNode. Therefore ChartNode.SetMarkerDashPattern should be used to set the marker dash pattern. It defaults to a solid line. Alternate entries in the array represent the lengths of the opaque and transparent segments of the dashes.

Some dash patterns are defined. They are DASH_PATTERN_DOT, DASH_PATTERN_DASH and DASH_PATTERN_DASH_DOT.

NOTE:  MarkerDashPattern is a double-array-valued attribute that determines the line pattern used to draw the marker. It defaults to a solid line. Alternate entries in the array represent the lengths of the opaque and transparent segments of the dashes. These patterns will be more recognizable with larger marker sizes.

Samples



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