Fixed dpi issue in the document format

[Pétery Tamás]

There is the document's properties panel to set up the size and measures in an svg.

You can set a custom document size in whatever units, which the document will use as a page size and
set up a viewbox to store the data effectively.

When setting up the document to display mm units and the document size to be in mm values,
and the viewbox to be in px, all is fine -on the surface-.
But, whenever a selected object's size display unit is changed from mm to px in the top spinbox, it displays the px equivalent calculated at the 96 dpi formula, and not of what's set via the viewbox attribute.

Test case:
viewBox="0 0 9500 9500"
  height="19000mm"
  width="19000mm"

drawn square in document covering the page, displayed to be 19000 mm / 19000 mm -good-
or
71811,024 px / 71811,024 px -not good- (9500 px / 9500 px is expected)

[Mc (mc...)]

(explanations on IRC about units)

[Pétery Tamás (lazur)]

Since then I learned that the document size setup is "outside svg" units, sort of to be scaled in real word and that the viewbox is what defines the document size in user units (px).

Then, the problem is the height/width of objects are displayed in px based on the conversation of the "outside svg" given units at 96 dpi, and not displaying the real user units -as requested&defined with the apropriate document width/height and viewbox ratio.

Maybe a pxxuu or simply uu (userunit) would be a nice add to the dropdown list of the measure units for more convenience.