I draw a perfect black filled circle and print to PDFCreator. This results in a 127KB pdf file and when I zoom in to 6400% with acrobat reader, the circle looks like a bitmap with jagged edges. It also looks like the circle was created in strips with small gaps between the strips.

Doing the same test with coreldraw, it created a 3KB pdf file and when zoomed to 6400% it looks smooth like it should be.

Is this a bug?

I don't believe this is a bug. I think Inkscape rasterises the image before printing.

If you want a PDF of your image that isn't rasterised, select PDF from the list of filetypes when you save the image. I know PDF support is something they've been working on so I'm not sure what the results will be like in 4.5. I know a black circle works just fine But there will be some features that PDF's don't understand, such as blur.

You're absolutely right. I didn't even know/expect inkscape to provide PDF export!
Repeating the same experiment, inkscape generated a 2KB pdf file and the circle is perfect!

Maybe I'd start using inkscape to author PDF file.

As of the next release we should read them too.

Will it be possible to print the blur effects to pdf as well?

Only as embedded bitmaps as far as I know, pdf doesnt have a native capability to do blur, so you have to rasterise it.

I have read several times that inkscape supports pdf transparency but i must be doing something wrong because i can't get it to work. i just get an opaque shape where my gradient (solid to transparent) shape is when I save as pdf... help?

I just got transparency to work but only with solid colors, not with gradient fills, is this possible?

Also, is it possible to rasterize blurs and transparent gradients before exporting to pdf?

OK I think I have this figured out. It seems that you cannot maintain a gradient in pdf format with anything but full (255) alpha setting on the gradient colors. You can achieve translucency across an entire shape in pdf's if you use inkscape's 'opacity' setting. Is this correct?

I am still curious about whether it is possible to rasterize blurred elements and/or alpha-gradients in order to export these effects to pdf. Thanks.

You can rasterise anything you want, simply select and do alt+b to create a bitmap copy.
Be warned the visual effect of doing this on blurred objects will initially make it look like its got darker,
its because theres 2 objects stacked on top of each other. Turn the master opacity on the vector one to 0% while you export.

edit:
Just realised theres a bug wrt this and blur, it only rasterises teh original shape bounding box, not the blurred one. Group a shape that
is larger than the blurred object with it and set the big shapes fill/stoke to nothing. Do the alt B on that group, that will make the copy big enough.

thanks simarilius, that helped, although rasterising the blurs and transparent gradients kind of defeats the purpose of doing the rest of the illustration in vector format. will we ever be able to export those effects to pdf? can you currently export those effects to pdf in adobe illustrator?

No. Illustrator can't even create a gradient with transparent stops.

I would expect the PDF export feature of Inkscape to automatically rasterise elements not support by PDF, like Illustrator does when saving as EPS.

microUgly wrote:No. Illustrator can't even create a gradient with transparent stops.

I would expect the PDF export feature of Inkscape to automatically rasterise elements not support by PDF, like Illustrator does when saving as EPS.

I'm sure it will at some point, just a matter of someone getting round to it (the speed at which things get fixed is usually directly proportional to how many devs find it irritating and how irritating it is, if the devs dont do pdf much, it'll be a lower priority than something that regularly annoys them )