Is it possible to retain object graphics as vectors when printing to a postscript device?

So far I have not been able to do so. For example:

Open inkscape, new document
Create a rectangle with a black outline and fill (252,255,255)
Create a small black solid circle within that rectangle
Make 5 more copies of the circle and scatter around within the circle.
Print to a postscript printer with "save to file"

Result, the vector object is converted to a bitmap. (This file is attached.) Changing the fill from (252,255,255) to (255,255,255) prints to a smaller file, not because it is now using vector objects, but because it uses a BW bitmap instead of the color one. Nothing fancy here, no opacity or filters employed.

Many, many other programs do this too. ( Not all though, MS Word and PowerPoint embed vector operations instead of converting to bitmaps.) Does Inkscape printing to postscript devices use a library which might be shared with these other programs? If so, which library is this?

Thanks.

mathog wrote:Nothing fancy here, no opacity or filters employed.

The strokes of all the objects have a reduced opacity (alpha = 250). Set them to full opacity (alpha = 255) when exporting to a PostScript-based file format (or change the color to a dark shade of gray, if you want the objects to have a slightly lighter stroke).

mathog wrote:Many, many other programs do this too. ( Not all though, MS Word and PowerPoint embed vector operations instead of converting to bitmaps.) Does Inkscape printing to postscript devices use a library which might be shared with these other programs? If so, which library is this?

Since 0.47, Inkscape uses the cairo library for exporting to PDF/EPS/PS. Not at all related to proprietary Microsoft applications.

~suv wrote:

mathog wrote:Nothing fancy here, no opacity or filters employed.

The strokes of all the objects have a reduced opacity (alpha = 250). Set them to full opacity (alpha = 255) when exporting to a PostScript-based file format (or change the color to a dark shade of gray, if you want the objects to have a slightly lighter stroke).

(Sorry if this is a duplicate, I replied but it seems not to have posted.)

Where are you reading that alpha value? Near as I can tell Opacity is 100.0% on all 3 tabs (fill, stroke paint, stroke style) for both the rectangle and the black circles. There is also an "O" at the bottom of the screen showing 100 with only a down arrow available, the up arrow is grayed out. All of which indicate 100.0% Opacity. (Blur is 0%.) Version is 0.48 on Windows XP SP3.

Thanks.

Ok, I found the Alpha, it was "A" on the RGB color picker. I don't recall setting that to anything, but might have hit it by accident. Changed A for all objects to 255 (one at a time...) and printed to postscript and it came out as a vector. So I guess the answer to my original question is "be very, very careful". Is there some way to get Inkscape to warn when the drawing will be converted to an image on printing, and even better, have it say why?

Thanks!

that's a gotcha that gets me quite a lot, i.e. inkscape remembers some settings from last drawing, and sometimes opacity is not 100% as i expected. but i don't export to postscript btw.
as to making sure (finding) some perhaps complicated svg in inkscape doesn't have an object with less than one opacity...look for "opacity:0" in your favorite text editor or grep utility etc. as any opacity less than one will start with that string, and be followed by a decimal point and other digits.