IDLgrContour::GetLabelInfo

The IDLgrContour::GetLabelInfo procedure method retrieves information about the labels for a contour. The returned information is only valid until the next time the C_LABEL_INTERVAL or C_LABEL_OBJECTS property is modified using the IDLgrContour::SetProperty method, or the offsets are adjusted using the IDLgrContour::AdjustLabelOffsets method.

Syntax

Obj->[IDLgrContour::]GetLabelInfo, Destination, LevelIndex [, LABEL_OFFSETS=variable] [, LABEL_POLYLINES=variable] [, LABEL_OBJECTS=variable]

Arguments

Destination

A reference to a destination object (such as an IDLgrWindow or IDLgrBuffer object). The contour label information will be computed so that the requested font size is satisfied for this destination device.

LevelIndex

The index of the contour level for which the label information is being requested. This value must be greater than or equal to zero and less than the number of levels (refer to the N_LEVELS keyword in the IDLgrContour::Init method).

Keywords

LABEL_OFFSETS

Set this keyword to a named variable that upon return will contain a vector of floating point offsets, [t0, t1, …], that indicate the parametric offsets along the length of each contour line at which the contour labels are positioned.

LABEL_POLYLINES

Set this keyword to a named variable that upon return will contain a vector of contour polyline indices, [P_0, P₁, …], that indicate which contour lines are labeled. P_i corresponds to the ith contour line.

Note that if a given contour line has more than one label along its perimeter, then the corresponding polyline index may appear more than once in the LABEL_POLYLINES vector.

LABEL_OBJECTS

Set this keyword to a named variable that upon return will contain a vector of objects that represent the labels for each contour label.

Version History

5.1	Introduced