Hi Doug, Thanks for bringing the issue to our attention. As with many things that go on in the deeper levels of W3C, I can't say I understand all the discussion. But if it boils down to "is the default interface in SVG scrolling (ala scrollbars) or panning (ala clicking on region of the window to slide the whole scene around) ?" and "whether or not authors have choices to override those things," then it seems to me that a scrollbars interface for images is wrong from the beginning. It is arguably an artifact of working with very small images that were required in the very early days of HTML. If you're not averse to using VML in IE take a look at http://srufaculty.sru.edu/david.dailey/javascript/morpher/rectzoom.html -- it is a very early pre-SVG-in-the-browser thing I did to illustrate drawing a zoom rectangle on a bitmap and then panning on that. It could easily be rewritten without the VML, so it would actually run across browsers (someday I might get around to it). Experience with students (a few hundred) was that it was indeed quite easy to use for investigating large bitmaps.
I note that some of the draw and drag operations that one might use in something like http://srufaculty.sru.edu/david.dailey/svg/makeDragDrop.svg (which btw is not meant to pan) fails to work in interfaces like i-phone where dragging on the screen is interpreted differently than select and drag in a drawing app. How do we allow collective drawings to be annotated and adjusted in mobile-space is an interesting question for your webApps group. But I tend to concur with you that the natural mode in SVG would be panning rather than scrolling. The general premise of zoomed maps, be they of earth or large graphs (in the sense of graph theory) is that we wish to move our viewing window around through them. It is far more natural than the scrollbar which is oriented more toward the linear medium of text (characters concatenated into strings) : the underlying metaphor for communication in HTML. When given a two-dimensional screen, it makes sense to scroll and wrap things that are linear. If we had three or higher dimensional screens it might make sense to scroll and wrap 2-dimensional entities. If our screens were only linear (displaying one infinite line of text) then I'll bet we'd have chosen the pan rather than the scroll interface as default. But I again assert that HTML got it wrong when it came to handling of bitmaps -- the methodology worked fine for fluid text with occasional small graphics inserted as punctuation. When the medium itself is non-linear as is the case with SVG, pan and zoom are intrinsic to the medium. Should authors have choices? What author would ever say no? As long as opinions are sought... there's one. cheers David ----- Original Message ----- From: Doug Schepers To: [email protected] Sent: Monday, September 22, 2008 7:15 PM Subject: Re: [svg-developers] Feedback Request: Difference Between Scroll and Pan? Hi, SVG Community- Please see this thread for details on the discussion so far: http://lists.w3.org/Archives/Public/public-svg-wg/2008JulSep/0339.html Regards- -Doug Doug Schepers wrote (on 9/19/08 2:58 PM): > Hi, SVG Community- > > Based on feedback from browser vendors, and following some > implementations, the SVG WG is considering changing the way SVG handles > the 'overflow' property on the SVG root. This has implications on > whether scrollbars would appear for SVGs. Clearly, sometimes this is > desirable, but other times it may not be. The SVG WG is seeking author > feedback on this issue, before we make a decision. > > If you are interested in this topic, please read this thread: > > http://lists.w3.org/Archives/Member/w3c-svg-wg/2008JulSep/0013.html > > This will affect how browsers handle SVG 1.1 content, so please do let > us know if this impacts you (positively or negatively). > > If possible, please send comments to the SVG public list, [EMAIL PROTECTED] > > Regards- > -Doug Schepers > W3C Team Contact, SVG and WebApps WGs [Non-text portions of this message have been removed] ------------------------------------ ----- To unsubscribe send a message to: [EMAIL PROTECTED] -or- visit http://groups.yahoo.com/group/svg-developers and click "edit my membership" ----Yahoo! Groups Links <*> To visit your group on the web, go to: http://groups.yahoo.com/group/svg-developers/ <*> Your email settings: Individual Email | Traditional <*> To change settings online go to: http://groups.yahoo.com/group/svg-developers/join (Yahoo! ID required) <*> To change settings via email: mailto:[EMAIL PROTECTED] mailto:[EMAIL PROTECTED] <*> To unsubscribe from this group, send an email to: [EMAIL PROTECTED] <*> Your use of Yahoo! Groups is subject to: http://docs.yahoo.com/info/terms/
