Hi all, I also meant to mention that moving the primary (large) offset into a transform will also help a lot (not so many of your bits will be 'wasted' on essentially unchanging data):
<path d="M489409.9,-4379209.97 [...] becomes: <path transform="translate(489409.9,-4379209.97)" d="M 0,0 [...] svg-developers@yahoogroups.com wrote on 05/10/2006 08:54:13 PM: > Hi Bruce, Andreas, > > svg-developers@yahoogroups.com wrote on 05/10/2006 05:57:28 PM: > > > I agree the issue is coordinate accuracy but I am curious why the bug > > only shows up in the relative format. The starting coordinate is the > > same. Maybe the viewers parse relative coordinates differently. > > The problem is most likely that at the limit of precision you > can get things like: > > x == (x+1) > > Thus if you add 1 ten times in a row you end up with the same x: > x' =x; > for (i=0; i<10; i++) > x' = x'+1; > x == x' > > However it is very likely that if you were to > actually add 10 to x you would get a different number: > x != (x+10) > > So you would sort of see something like: > x == (x+1) > x == (x+2) > x == (x+3) > x != (x+4); x' = x+4; // this is a new 'representable value' > x' == (x+5) > x' == (x+6) > x' != (x+7); x'' == x+7 // another new 'representable value' > x'' == (x+8) > x'' == (x+9) > x'' == (x+10) > > This is exactly the difference between absolute and relative > coords. With relative coords you start with a _really_large_ number > and then add lots of relatively small numbers - meaning that the > 'round off' is large in percentage terms of the small numbers. So > meaningful error can easily accumulate over many additions. > > However with absolute coordinates you are always giving it the > whole (essentially infinite precision) number, which it then rounds > to the nearest representable value - there opportunity for error to > accumulate. > > You could compensate for this by occasionally inserting an > absolute coordinate set (essentially resetting the error accumulation). > > > --- In svg-developers@yahoogroups.com, "Andreas Neumann" <[EMAIL PROTECTED]> > > wrote: > > > > > > hm, I'd be interested to know whats the problem here, as well. > > > > > > I tested in other SVG viewers. Batik has the offset like ASV and > > Firefox, Apples Safari > > > renders it correctly like Opera. Firefox 3 renders it the same way > > than Firefox 1.5. > > > > > > My guess is that some viewers have problems with coordinate accuracy > > at certain viewBox > > > / coordinate range combinations, but I can't tell where the limits > > are. I know that Firefox > > > usually has more problems with coordinate ranges than other SVG > viewers. > > > > > > Any one knows more about valid coordinate ranges in SVG viewers? > > > > > > Andreas > > > > > > --- In svg-developers@yahoogroups.com, "brucerindahl" <rindahl@> > wrote: > > > > > > > > I have the following small portion of a GIS SVG mapping application. > > > > > The file shows a portion of a floodplain area in cyan using absolute > > > > coordinates. The red outline should be the same shape using > relative > > > > coordinates. The file displays perfectly in Opera 9 but is wrong in > > > > IE/ASV and Firefox. Any ideas on why this is happening?? > > > > > > > > http://www.lrcwe-data.com/tmp/relative.svg > > > > > > > > Thanks > > > > Bruce Rindahl > > > > > > > > > > > > > > > > > > > > > > > ----- > > 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 unsubscribe send a message to: [EMAIL PROTECTED] > -or- > visit http://groups.yahoo.com/group/svg-developers and click "edit my membership" > ---- > Yahoo! Groups Links > > > > > > > ------------------------ Yahoo! Groups Sponsor --------------------~--> Get to your groups with one click. Know instantly when new email arrives http://us.click.yahoo.com/.7bhrC/MGxNAA/yQLSAA/1U_rlB/TM --------------------------------------------------------------------~-> ----- 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/ <*> 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/
