Re: [Inkscape-devel] [Inkscape-user] the Scale setting and Display units

Am 21.09.2017 um 11:14 schrieb Eduard Braun: I'd like to contribute my experience to this discussion: Corel/Illustrator/Inkscape are important tools to create drawings for 2D lasercutting and sometimes outline milling, as a full-blown 2D-CAD program is too complicated for novice users and unsuitable for decorative shapes or art (text, bezier curves, path editing). For those who haven't seen it yet, this is lasercutting: http://www.cutlasercut.com/getting-started/what-is-laser-cutting-laser-cu... And this is how people use inkscape for it: http://www.cutlasercut.com/resources/drawing-guidelines/styles-examples Lasercutter manufacturers tend to suggest Corel Draw, but that costs money and is not available for Linux. Inkscape works good enough for the casual or hobbyist user. During the last five years I've seen almost all possible values of scaling errors between Illustrator, Inkscape and the open source lasercutting software VisiCut, but since 0.92 at least Inkscape does everything right. VisiCut uses SVG as import format; if a file contains no viewbox, it has to fall back to guessing the DPI based on "Inkscape"/"Illustrator" comments in the SVG. Switching between Inkscape and Illustrator may cause scaling errors, as Illustrator is (sometimes?) too stupid to import/export standards-compliant SVGs. It is always annoying to have px as the default *measurement* unit in the GUI; Corel Draw also has mm as the default. The SVG-internal units don't matter, except for cooperation with other software which is too stupid to parse the viewbox and assumes some fixed DPI (often 72 and not 96). Changing the internal units is annoying, because suddenly users need to remember a different scaling factor to fix up the broken import of whatever driver they use. If I could choose the defaults, I would therefore vote for mm in the GUI and 96-DPI-pixels in the SVG internal units (plus viewbox, just as it was in 0.92). This should also match the defaults of Corel/Illustrator, except maybe for their arbitrary choice of DPI. Please don't add any more question dialogs that the average user doesn't understand, as the current DPI-conversion one is already enough (but was unavoidable). Regards, Max