On 03 Feb 2003, Lars Clausen wrote: > On Mon, 3 Feb 2003, John Edstrom wrote: >> On Mon, Feb 03, 2003 at 09:39:58AM -0600, Lars Clausen wrote: >>> On Sun, 2 Feb 2003, John Edstrom wrote: >>> > So far my biggest concern with a dot2dia transformation is that dot >>> > uses splines and dia doesn't. Some of dot's edges get pretty baroque >>> > in complex graphs and arcs and polylines can't do equivalently >>> > tortuous paths as well. >>> >>> Can't you use Dia's beziers? As I understand it, there are standard >>> translations between most such things. >> >> My background is not in graphics and I didn't know that. That would >> simplify things immensely. Is there a list of such algorithms >> anywhere? [...] > > Note also that Dia's "bezier" isn't really a Bezier line. It's a string > of line segments (I believe Bezier) with 4 control points each. The xfig > import plugin has some hacky translation from FIG style splines to Dia > beziers, but it's not exact.
Some more update on this: While Dia's lines are indeed fragments of cubic beziers, it's not trivial to translate from B-splines or Calmutt-Rom splines. Boehm has a paper that describes the appropriate insertion of knots to do a full translation, but it's beyond my current time limits. I'll let the xfig import just use the rough hack I did earlier. It appears that dot splines are actually beziers, which should make the conversion easier. I haven't found any more info other than the fact that they're called beziers internally. -Lars -- Lars Clausen (http://shasta.cs.uiuc.edu/~lrclause)| Hårdgrim of Numenor "I do not agree with a word that you say, but I |---------------------------- will defend to the death your right to say it." | Where are we going, and --Evelyn Beatrice Hall paraphrasing Voltaire | what's with the handbasket? _______________________________________________ Dia-list mailing list [EMAIL PROTECTED] http://mail.gnome.org/mailman/listinfo/dia-list FAQ at http://www.lysator.liu.se/~alla/dia/faq.html Main page at http://www.lysator.liu.se/~alla/dia
