ImageGear for C and C++ on Windows v19.10 - Updated
Modify Annotations
User Guide > How to Work with... > Annotations > New Annotation API: ArtX > How to... > Manage Annotations > Modify Annotations

As long as you are in Edit mode, marks can be modified.

As with creating marks, there are two ways to modify marks:

Geometric changes (like moving and resizing) are done automatically, as a result of ART GUI implementation, as shown in Creating a Mark via the Toolbar. To make other changes to a mark, your application makes a simple call to the mark's functions.

The technique for modifying marks via function call is used in the ART GUI dialogs code. The marks attributes can be modified using the appropriate functions.