The GUI Magnify interface is similar to the GUI pan. A similarly named set of functions is provided, namely: IG_GUI_magnify_window_create(), IG_GUI_magnify_update(), and IG_GUI_magnify_track_mouse(). You use these functions in the same way that you use the GUI pan functions. The difference is in what the user sees.

The magnify window is first created using IG_GUI_magnify_window_create(). Thereafter, whenever the user clicks or drags the mouse pointer in the image window, your application can issue a call to IG_GUI_magnify_track_mouse() to cause that portion of the image to be shown magnified in the magnify window. A scroll bar is provided in the magnify window. When the user drags this magnify window scroll bar, ImageGear automatically changes the magnification factor. Your application can refresh the magnify window, if needed, by calling IG_GUI_magnify_update().