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- Linda Murphy (murphy@dccs.upenn.edu) wrote:
- | Subject: Keeping HTML Simple & Format negotiation between Browser & Server
- | Date: Thu, 27 May 93 09:46:03 -0400
- | From: murphy@dccs.upenn.edu
- |
- | There's been a discussion on www-talk about how complex HTML should
- | become -- and the building opinion seems to be: keep HTML simple, and
- | allow more complicated formats to be embedded "in-line" in the HTML,
- | and negotiated between the server and the client.
- |
- | [...]
- |
- | Problems with this model:
- |
- | 1) If the browser starts up another application to handle a portion of
- | the document in a foreign format, what happens if that item in the
- | document was SUPPOSED to be in-line with other portions of the
- | document? How does the browser pull it back into the display of
- | the document and make it part of the whole?
- The Macintosh and Microsoft Windows systems are moving toward compound
- document architectures, as is X11R6. This shouldn't be an
- insurmountable problem.
- With X, one could look at an imbedded object, try to determine its
- appropriate size, then ask a renderer to image a file into a
- sub-window inside the browser's viewing area.
- |
- |
- | 2) What if one wants to put hot-spots (links) into one of these
- | foreign format objects? For example, suppose one wants the user to
- | be able to point & client on a portion of the mathematical formula,
- | which is linked to another mathematical formula (or a graph, or a
- | piece of text, etc) which more fully explains it?
- |
- This is the biggest argument for always providing a canonical image
- representation of non-plain-textual data.
- My dream for ultimate flexibility in the browser would be for the
- server and the browser be able to negotiate the browser's needs for a
- canonical, viewable image of the document.
- 1) The browser would ask what size the image (or paper, or whatever)
- is designed to be viewed at.
- 2) The server would report the designated image size, along with a
- summary of its capacity for generating other image sizes.
- 3) The browser would request an image of whatever parameters best suit the
- available display.
- 4) The server would either
- - Image the document according to the browser's specifications,
- caching it for future retrieval by browser's with similar needs.
- or
- - Send the one image closest to the browser's requirements for that
- document if no dynamic image generation were possible
- Each link in the image would consist of:
- - a union of rectangles designating the boundary of the link
- - a URL
- - a set of flags, perhaps including one indicating whether the link
- should be decorated by the browser, or whether the link is already
- decorated in the image
- 5) The browser would scale the image if necessary (obviously it would
- be preferable for the server to be able to generate an image that
- is best suited for the browser, but if not the browser would scale
- the image and the corresponding regions down), then present it to
- the user.
- This way, links could be provided in a reliable fashion within ANY
- kind of complex data, and exterior viewers could be used to do a
- better job of imaging a particular kind of data to other output
- devices at the browser's disposal. E.g., a PostScript document would
- be available on screen at an appropriate resolution with links
- included, and the same document (or a version of the document that
- didn't have the links decorated) could be sent to a file or a printer.
- It might even be possible to provide the same set of links with
- something that is imaged at the browser's side if there is a
- definitive representation for that data type that can be relied on.
- Something similar could be done with sound files by
- providing a start and stop time for a particular link. Video files
- likewise, with start, stop and a union of rectangles.
-