On Apr 3, 2010, at 10:58 AM, Krzysztof Kosiński wrote:
W dniu 3 kwietnia 2010 19:47 użytkownik Jon Cruz <jon@...18...> napisał:
Oh, while you were in there did you happen to get a feel for how changing our DPI might work? Originally it was hardcoded into individual calculations, often as ".8", "0.8" or "1.25". We had been trying to at least minimize the use of those.
Unfortunately DPI handling is not very related to desktop coordinates. When I worked on the patch, I found only 1 place (related to bitmap copy) where I found any DPI-related code.
Well, there are a few different ways DPI affects things. One is in bitmap import, but another is with display and matrices.
For the one most related to the axis inversion, one would want a display with a high pixel resolution result in more actual pixels assigned per px than one with a low resolution display. Common display PPI are 72, 90, 96 and 144. CSS2, CSS2.1 address this, and CSS3 might complicate it a bit more.
Then we would want a *per document* DPI setting that might involve a viewBox, etc. Accounting for that might be a different factor.
Additionally, I'm not sure how exactly DPI handling should work. Should this be a global setting of the document, or something that reflects the monitor's resolution? Some blueprint would be useful.
I'll get some stuff together on the wiki for the big picture. In the mean time you might look at the zoom correction factor in the "Interface" preferences tab. That is part of a work-around for not detecting/accounting for physical monitor PPI. I think I also saw a "1.25" in a win32 cpp file, but I've not chased down its impact yet.
Oh, and I've already been dealing with monitor query stuff for the color profiles. I'll look to see what I can give you for physical monitor DPI, especially for multi-monitor setups. (And we might see a lot more of those, as the iPad, iPhone and iPod touch now have an app that makes them work as an additional monitor)