Image maps are images which are embedded in a HTML page. You can assign a message and a URL to parts of the image. If the mouse cursor stands still over one of that parts, the message is shown as tooltip. By clicking the URL is loaded.
PhotoLine represents these "sensible" parts of the image as layers. You can assign every layer a URL and a message. Sometimes a layer has only been created in order to define an image map entry for the covered area, but the layer itself shall not appear in the resulting image. Therefore there is the switch Layer Invisible which ensures, that the layer is not shown if the picture is exported via Image Map/Image Map Export.
The assigned commands will be used on exporting as PDF- and as SWF-file, too.
Using SWF it is possible to define buttons this way. The URL has a speciality in SWF: if a frame identifier is appended by using "::", this identifier controls, in which frame the URL will be loaded. There are some predefined values: