0. XHTML Server-Side Image Map Module

This section is informative. For the normative version, see [XHTML2].

The Server-side Image Map Module provides support for image-selection and transmission of selection coordinates. It requires that the Object Module (or another module that supports the object element) be included. The Server-side Image Map Module supports the following attributes:

Implementations: DTD, XML Schema

ismap = "ismap"

This attribute indicates that the associated embedded resource is to be treated as a "server-side image map". When selected, the coordinates within the element that the user selected are sent to the server where the document resides. Coordinates are expressed as pixel values relative to the embedded resource, and start at (0,0) at the top left corner.

When an ismap attribute is specified, click events are not delivered to the embedded resource, regardless of its type.

In the following example, the active region defines a server-side image map. A click anywhere on the image will cause the click's coordinates to be sent to the server.

<p href="http://www.example.com/cgi-bin/map"
      src="map.png" ismap="ismap">
   Our location.
</p>

The location clicked is passed to the server as follows. The user agent derives a new URI from the URI specified by the @href attribute of the element, by appending `?' followed by the x and y coordinates, separated by a comma. The link is then actuated using the new URI. For instance, in the given example, if the user clicks at the location x=10, y=27 then the derived URI is "http://www.example.com/cgi-bin/map?10,27".

User agents that do not offer the user a means to select specific coordinates (e.g., non-graphical user agents that rely on keyboard input, speech-based user agents, etc.) must send the coordinates "0,0" to the server when the link is activated.