Read the section of perspective correctness here for example: http://en.wikipedia.org/wiki/Texture_mapping
Cheers /Erik On Tue, 22 Jan 2008 15:12:51 +0100, ~:'' ありがとうございました。 <[EMAIL PROTECTED]> wrote: > Erik, > > it's certainly not 3D, there's no question of rotation, or animation > to give parallax. > this is 2D perspective distortion. > > unless I'm misunderstanding something significant. > > please could you elucidate. > > regards > > Jonathan Chetwynd > Accessibility Consultant on Media Literacy and the Internet > > > > On 22 Jan 2008, at 14:00, Erik Dahlström wrote: > > Jonathan, > > I don't see it as peculiar at all since "SVG is a language for > describing > two-dimensional graphics in XML." [1] (the lighting filters are the only > exception to that AFAIK). In any case what you are talking about is 3D > graphics. There is no reason perspective correct transformations > couldn't > be included in a future version of the SVG specification(s) however. > > Cheers > /Erik > > [1] http://www.w3.org/TR/SVG11/intro.html > > On Tue, 22 Jan 2008 14:39:01 +0100, ~:'' ありがとうございま > した。 > <[EMAIL PROTECTED]> wrote: > > > Erik, > > > > isn't it peculiar that a fairly simple perspective distortion is > missing > > from the SVG spec? > > ie just as you describe by increasing scaling along a line > > > > especially given it's importance and history in western art? > > > > removed the typo, and updated slightly, thanks > > > > regards > > > > Jonathan Chetwynd > > Accessibility Consultant on Media Literacy and the Internet > > > > > > > > On 22 Jan 2008, at 12:05, Erik Dahlström wrote: > > > > On Tue, 22 Jan 2008 12:52:47 +0100, ~:'' ありがとうござい > ました。 > > <[EMAIL PROTECTED]> wrote: > > > > > there's a simple Brick Pattern here: > > > http://peepo.co.uk/temp/brick-pattern.svg > > > > You might want to remove the space in patternUnits="objectBounding > Box". > > > > > feDisplacementMap may well be a possible route, however it does > seem > > > somewhat complex in the relation to the concept. > > > > Not sure that would be able to give true perspective correct images > > though. > > > > > On 21 Jan 2008, at 23:27, Frank Bruder wrote: > > > > > > Hi, > > > > > > would be great if full 3x3 matrices--without the third row > implicitly > > > set to [0 0 1]--were allowed for transform values. This would allow > > > for perspective distortions. But I'm not sure if this wouldn't > be too > > > difficult for implementors since singularities (the horizon) would > > > need to be dealt with, in case they become visible. > > > > Indeed the 2d transforms that are in SVG today are not capable of > > handling > > this case. > > > > > There was a question before regarding perspective distortion of > text. > > > And I remember someone suggested using the filter primitive > > > feDisplacementMap. But no solution for creating the correct image > > > data to use for in2 was found then. Maybe this was resolved in the > > > mean time. > > > > There are other tricks, for example drawing the image repeatedly > (with > > clipping) while varying the scale transform. > > That would probably look a bit ugly though, possibly it could be > smoothed > > out a bit by using filters or masks. > > > > Cheers > > /Erik > > > -- Erik Dahlstrom, Core Technology Developer, Opera Software Co-Chair, W3C SVG Working Group Personal blog: http://my.opera.com/macdev_ed ----- 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/
