Annotation Functions (Document and Medical Imaging toolkits):
 Size, Position, and Shape
  Using Window Coordinates to Select Objects

Selecting all objects in a rectangle:

L_AnnGetSelectCount

L_AnnGetSelectItems

L_AnnSelectRect

Selecting an object at a particular point:

L_AnnSelectPoint

Getting the bounding rectangle of selected objects:

L_AnnGetSelectRect

Identifying an object at a particular point:

L_AnnHitTest

L_AnnSendToBack