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- On ISMAP vs Figure Anchors.
- ==========================
-
- I agree that bot the ISMAP technique of returning coordinates to a
- server, and the FIGA (HMML) technique of overlaying anchors on
- pictures have uses. I feel that in fact their application areas
- are quite separate.
-
- It would be infuriating to have a ISMAP server which had some
- areas selectable and others not, where you got back an error
- message if you clicked in the wrong place. But on the other hand,
- a good cyberspace web will have nodes on which you can click anywhere
- to change your point of view.
-
- So let's specify both. Now for protocols.
-
- PLEASE KEEP OTHER INFO OUT OF LINKS
-
- The ISMAP attribute has the problem that
- it includes information in the link which ought to be
- sent from the server when the map is retrieved. I would
- suggest a methodname "SPACEJUMP" say in the Allowed: return
- field. This allows the server to tag things as spacejumpable
- however you ahve got to them. If for example you convert
- a URN ionto a URL and retrieve the document, then you get
- a spacejumpable version. If you have a graphics machine.
- Some documents may become spacejumpable. Having to put information
- like that in the links is bad because
-
- 1. It is duplication of information which implies
- incorrect information.
-
- 2. It may change with time.
-
- 3. It may be a function of client and server
- capabilities.
-
- The same applied to the "type=immage/gif" which has been
- suggested and Pei mentioned. PLEASE DON"T put type information
- into the link! PLEASE use the full protcocol, using the libwww
- or otherwise.
-
- Scale coordinates please
-
- I would point out too that we can forsee smart servers which will
- for example, as a function of the client, automatically generate or
- select
- a 800*600 GIF to send instead of a 1200*1000 JPEG. This will make
- transfers onto low-res and/or low-bandwidth clients much faster.
- It will be completely automatic. It means that ISMAP coordinates
- should be scaled to say 0 - 1.0 in the size of the picture,
- as pixels won't have much meaning. Same applies of course anyway
- to postscript pictures which have no concept of pixel size.
-
-
- There's my 2c for today.
-
- Tim
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