Image Maps

Image maps allow a user to click with the mouse on an image, perhaps to select a location from a map. The XY coordinates of the click are passed to the specified URL as a query; for example, ?100,23 could be added to the original URL. Note carefully that the border coordinates can be returned, ie the range is from -3, -3 to MaxX+3, MaxY+3.

An image map is a special type of hyper-text link, so use the following HTML:

<A HREF=url> <IMG SRC=file.GIF ISMAP> </IMG> </A>

The given url will point to your program which can decode the query coordinates.

In the httpd configuration directory, the file IMAGEMAP.CNF has entries for maps which pick up circles, rectangles and polygons, and call a given URL. I have not found any documentation for this. However it would be a nice wee project to make these maps work with C - go to it!

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