[trunk] embedded SVG rendered as raster images

• Jan 26, 2012 - 23:53
Type
Functional
Severity
S4 - Minor
Status
closed
Project
MuseScore

Setup: rev. 5255; compiled with latest Qt SDK (Qt lib 4.7.4) under Ubuntu 11.10 AND under Win7

Steps:

1) open the attached score: it contains a single stave and a vert. frame with an SVG image inserted using the VBox contextual menu;
2) zoom to 200%: the image is clearly rendered as raster.

The original SVG image is attached also as a separate file for reference.

The same happens in exported PDF.

Analysis: the SvgImage class uses the buffer member of the Image base class to render the image contents (see function void SvgImage::draw(QPainter* painter) in file libmscore/image.cpp).

buffer is of type QPixmap: this is why the image is rendered as raster.

Note: I tired to get rid of buffer in SvgImage and directly use
    doc->render(painter)
in SvgImage::draw(): the image is then correctly rendered as vector, but I could not find the correct scaling factors between the doc size, the image size, the bbox size and so on; for this reason I cannot supply a patch.

Thanks,

M.

Attachment Size
trunk_test_svg.mscz 4.09 KB
ornament_002.svg 2.37 KB

Comments

• Jan 27, 2012 - 08:48

fixed in r5259.
The pixmap is used always as a cache for the rendered svg. Problem was that the cache was not set dirty on resize.
For print now direct rendering is used. However i did not checked how qt actually does pdf rendering of svg's.

Reply

• Jan 27, 2012 - 19:18

Thanks Werner!

SVG graphics are indeed displayed 'as vector' on screen. A quick test with a simple PDF export confirmed that PDF also is behaving 'vectorially' (probably because PDF files are created via QPrinter, see function MuseScore::savePsPdf() in file libmscore/file.cpp).

So, the issue can be happily closed.

Thanks again,

M.

Reply