Comment 51 for bug 1738774

(In reply to bugzilla2 from comment #44)
> Ok,time for an update here too :)
> I use SVG-Icons quite a long time now, and for me those always look better
> than the png versions. I just did an comparison, and the png-version really
> looks terrible on an high-dpi monitor with 175% scale.
>
> As far as I remember, SVG primarily was an issue on Linux? So can't we just
> make SVG default on Windows?

Not at all!

There is no means currently to directly render the SVG into the GUI, meaning they will always be rendered to a bitmap and held in config (per user profile) for the display resolution in use. Look in %APPDATA%\LibreOffice\4\cache for the entire SVG icon theme rendered to PNG at scale. For performance the entire SVG of the active icon theme is parsed and the corresponding PNGs built on first launch.

The project deploys resolution appropriate 100% (so 96pdi) scaled PNG at three icon sizes small (sc 16x16) large (lc 24x24) and extra large (32 32x32). They are hand lay ups from the source SVG. They render correctly for most non-HDPI/non-scaledUI and remain appropriate for UI or os/DE scaling up to about 150%. They then start to look pixelated at 150% or above. Since 96-120dpi displays remains the norm for the vast majority of users there is no justification for doing more with the SVG.

Only if your os/DE is being scaled (as response to HiDPI, or by user setting) does it make sense to use SVG. Do it manually, the automated resampling and rendering of the SVG is inferior to the system deployed PNG at the default 100%, i.e. 96dpi resolution. The mechanism for "detection" of HiDPI (and so automated use of a resampled set of SVG icons)is "thresholded" at 168 dpi.