Hi Friends (especially ~suv )
This seems related to bug #299362 here: https://bugs.launchpad.net/inkscape/+bug/299362 which I know I made a huge mess of it. So I don't dare add anything to it, for fear of making it worse Plus, there are differences which seem notable to me.

It seems related, in that the results of the interpolation are spread out some distance from the originals. And I don't mean that the interpolation was performed properly, except that it's far away (that happens too, but I don't mind moving it back, as long as it worked properly) (which happens with most if not all extensions for me). I mean that the interpolated lines touch one another when it works correctly, while in this case, they're 5 to 10 times the distance away from each other. In bug #299362, the same thing happened with radially tiled clones, simply drawing single dots (Pencil tool and Ctrl + click), applying a radial gradient to a group of ellipses, and clipping -- in all cases, some kind of transformation had been used, including Fit Page to Selection, and in all cases, whatever I was drawing was displaced on the canvas (seemed to disappear, but I later found them far away from where I was working). It was reported in Inkscape 0.46 on Windows XP sp3.

The part that seems not related, is that this bug in the past affected the entire document, so that if I duplicated the steps in the same document, the same problem recurred. But they didn't happen in a fresh, new doc. In this case, I duplicated the steps in the same document, and it works properly. (It does also work properly in a new document, btw) While I have not used Fit Page to Selection, I have used some transformations -- rotate and flip. This is in Inkscape 0.48 on Windows 7, 64-bit.

Questions - 1) Is it a bug? 2) Is it related to #299362? 3) Should I add a comment to #299362 or start a new report?

So here is the file. Sorry for the small size, I'm working on animating my avatar. Don't want to scale, since transforms may be part of the problem. 800% zoom should work well, and hopefully it will open already zoomed.



Thank you very much

I haven't read all the details of your comment yet - but please don't add yet another issue to bug #299362. Yes, it is known and reported that changing the page size or orientation can trigger bugs with various tools/objects/extension scripts. However, each of those will require separate fixes - tracking them all in one single report makes bug triage unnecessarily complicated.

The tiled clones issue already has a separate report (as commented in your report) , and some effects that resizing the page (or working inside a group which had been moved or scaled) or scaled/transformed shapes (ellipses, stars, polygons) can have on the interpolation extension have been discussed in an earlier topic by Khorf: Interpolate Bug?.

The problem is that the lower, green path has an explicit 'transform' attribute (same what triggered Khorf's problem).

Easy workaround: select the green path, nudge it with the cursor key one step up (or to the side) and back, then apply the interpolate extension (the nudging causes the path data to be rewritten).

The underlying issue is the same as Bug #491188 in Inkscape: “Interpolate Extension fails if Preferences are set to Preserved” (disregard the summary line - the problem is not how a path got such an explicit transform attribute, but that if a path has it, the extension fails to produce the expected result. The explicit transform attribute might be due to certain preference settings or to other circumstances - but none of those by themselves are a bug).

Aaah, thank you ~suv
You've answered all my questions. I'm glad that no further action is needed by me