Backgrounds: Resize vector images before rendering to bitmap

[humdinger]

When the "Placement" is set to "Scale to fit", SVG images should be resized to the screen resolution before they are rendered into the bitmap. (Possibly WonderBrush files, too, though I dunno what happens if those include bitmaps deside vector shapes.)

Currently, it seems, the SVG is rendered in it original resolution and then the bitmap is scaled up to the screen resolution, resulting in blurry images.

The nanosvgtranslator provides a "Scale" parameter in DataTranslation prefs.

I attached one of zuMi's excellent SVG backgrounds if anyone decides to work on this and needs a test file.

[humdinger]

zuMi's SVG background "Cociu"

[waddlesplash]

Translators accept a BMessage to specify optional parameters. Likely all the "vector" translators (HVIF, WonderBrush, SVG, etc.) should accept one with a "size" parameter and render as appropriate.