Routines (alphabetical) > Object Classes > Graphics Object Classes > IDLgrROI::PickVertex

# IDLgrROI::PickVertex

Syntax | Return Value | Arguments | Keywords | Version History

The IDLgrROI::PickVertex function method picks a vertex of the region which, when projected onto the given destination device, is nearest to the given 2-D device coordinate.

## Syntax

Result = Obj->[IDLgrROI::]PickVertex( Dest, View, Point [, PATH=objref] )

## Return Value

Returns the index of the nearest region vertex. If two or more vertices are equally nearest to the point, the smallest index of those vertices is returned.

## Arguments

### Dest

An object reference to an IDLgrWindow or IDLgrBuffer for which the pick is to occur.

### View

An object reference to the IDLgrView containing this region.

### Point

A two-element vector, [x, y], representing the device location used for picking a nearest vertex.

## Keywords

### PATH

Set this keyword to a single object reference or a vector of object references. This keyword specifies the path in the graphics hierarchy to map the device position to a location in the data space of the region. Each path object reference specified with this keyword must contain an alias. The selected vertex is computed for the version of the object falling within the specified path. If this keyword is not set, the parent properties determine the path from the current object to the top of the graphics hierarchy and no alias paths are pursued.

## Version History

5.3 | Introduced