SVG displayed image size

[Matt Huszagh]

Hello,

SVG images are displayed smaller than I would expect in Emacs. How is
this controlled? I spent a while looking through image display functions
in elisp, but was not able to figure out how Emacs determines the actual
size of the image display in, e.g., image-mode. I've compiled Emacs with
SVG support, of course.

For instance, I have an SVG image with the width attribute specified as
about 20mm, but it displays as well below 2cm on my screen. I have an
HiDPI display and I expect these things are related.

Thanks for any pointers!
Matt