I know how it works and I know what should be the outcome. I even used it few times. I also created a test svg with few bitmaps and lines and PixelSnap did it's work. But not for certain document I've recently created. In that document id behaves normally... but does nothing. Can anyone take a look?
http://www.mediafire.com/file/65zc8myry ... etch02.svg

Hi,

I'm the author of PixelSnap, so I'll look into this. Could you please post an official bug at http://code.google.com/p/pixelsnap/issues/entry ?

Thanks!
Bryan

Whatever you say, I'm grateful for the extension, but don't you think we would rush things to much? I mean we're not even sure it's a bug? Or did you look into my svg already?

I can confirm the bitmaps in the file seem to snap horizontally but vertically they fall in the pixel middle.

Not exactly in the middle. Sorry if you knew that.

OK, I'll fill the bug report tomorrow. Good night!

Hi Bucic, sorry, didn't mean to make a hassle for you -- it's just easier for me to manage the issues centrally via the issue tracker. Doesn't really matter if it's not a confirmed bug yet. It just means it doesn't get forgotten if I don't get to it immediately.

Anyway, I'm more than happy to look at the SVG file from here, which I've now done... and yes, I can confirm your observations. The bitmaps snap horizontally but not vertically. I might not get a chance to look into it until later next week.

If you could still post an official bug on the issues page, that would be helpful, thanks, just as a reminder for me.

Are you kidding me?! It's in my interest and the least I can do show my appreciation to the author of such a useful extension

Edit:
Bug report submitted http://code.google.com/p/pixelsnap/issues/detail?id=9

Any news?

Hi Bucic, yes, good news. I've finally had a chance (in the last couple of days, during my Christmas) to have a proper look at this. Good news: I've located the bug, and I've fixed it in my local copy of the code. I need to do a few tidy-ups and some testing to make it production-ready, but expect to see a downloadable file in a few days (probably on my day-after-New-Year's holiday).

Sorry for the delay on this!

Briefly, the bug is due to the an object's ancestor(s) having a non-integer translation (in other words, the group or layer that an objects is part of isn't aligned to a pixel boundary). Until now, PixelSnap didn't look at the hierarchy above the currently selected objects. So if a Layer is shifted by a fraction of a pixel, none of the selected objects would be aligned correctly.

In your case, the "bmp" layer is shifted by -29.375 pixels. You can see this if you open up the XML editor and look at the "transform" attribute of the "bmp" layer. You can fix it manually by setting just that value to -29. My upcoming release will do this automatically.

How does a layer get shifted like that, without you ever asking Inkscape to do so? When you change the Document dimensions in the Document Properties dialogue, Inkscape automatically adjusts each Layer's translation to account for the (slightly weird) fact that all objects are positioned relative to the non-zero edge of the page (if it were me, I'd position all objects relative to zero, so they wouldn't shift when I change the page height, but higher powers than me have decided otherwise!)

Great! As I said before you don't owe me nothing and I owe you a lot Thanks for the technical explanation too.

Initially I didn't see any use for your extension but that was before I learned about grid snapping and its importance. Please post a release notification in this topic, OK?

Hi Bucic,

I've fixed the bug you've described -- it was an issue for me a couple times, too, so I'm glad to have it fixed. I'm not ready to make a full new release yet, but you can download the new files from the bug report page here: http://code.google.com/p/pixelsnap/issues/detail?id=9

Could you please give that a quick test and post a reply on the bug report page how well it works (or if it doesn't work!)

I treated the same file with Extensions - Modify path - 'Development pixelsnap', default options after simply selecting all objects by Ctrl+A. Effect? Seems to be fixed.

Thanks for your work on this bug!

P.S. I've attached the modified drawing in a comment on code.google.

Here's a little demo
Although I didn't use layers in this one. It was a quickie.

P.S. Poor rasterheads


Edit:
And an improved one. All Inkscape.

Another issue report submitted http://code.google.com/p/pixelsnap/issues/detail?id=10
I used the Pixel Snap dev. version you've send me.