On Wed, 2008-12-17 at 09:33 +0100, Werner Hoch wrote: > Hi Peter, > > great work, I'm testing (e3d0a2f6a09cce161021a15) > On Mittwoch, 17. Dezember 2008, Peter Clifton wrote: > > The cairo branch has seen a great deal of improvement, and I'd love > > some testing feedback. Is it fast enough.. are there any rendering > > artefacts I've missed, have any behaviours changed (which shouldn't > > have). > > Looking at the file gschem/tests/alignment.sch: > > The tab width has changed. The old definition of the tab was > "8 times the width of the letter "b"". > Now the width is the same as in the add text and edit text dialogs. > It's ok to me, it's just different.
Yes, wasn't quite sure what to do with tabs. I can teach pango to line tabs up at various positions, or I could strip out tab characters and replace them with fixed width place-holders. I figured that it would be worth just seeing how the default pango behaviour sat with people for a first cut. > Zooming way out, the rendering of the overbars is wrong. I get three > long lines in the boxes of the alignment test. The long line at the > overbar test on the right looks wrong, too. Is that because that piece renders solid at 1px width, rather than fading out like the rest of the text (due to anti-aliasing). If so, I probably need to change the way I'm hinting to pixels. > Looking at the file gschem/tests/geda_fonts.sch or alignment.sch: > > The escaping of the '\' character doesn't work properly. The escaping of > regular characters doesn't work, too. Examples: > x\\x should become x\x > x\ax should become xax > > This also affects drawing of overbars if you mix the escaping with > overbars: > \\_abc\\_ should become \_abc\_, but it is rendered as \abc\ with an > overbar over the last four characters. Good catch. I forgot about escaping when I wrote the ugly \_ stripper and pango-attribute attacher code. The code is vile, so I wanted to re-write it anyway. > > I've coded up a Pango renderer subclass which draws overbars > > (although it uses a magic constant for positioning them). Does this > > work for the font gschem picks up on your system? Do the overbars > > look OK? > > The position of the overbar looks fine at all different text sizes. Its position is 80% of the line-line height up from the baseline. I started from my vague idea of what the metric between line-height and font ascent was, then added a bit so it looked nice. There might be a way of measuring a real ascent from pango, but pango is really complex - I'm not quite sure how! > Misc things: > - there are too many grid lines when zooming out. > Maybe a darker color could help a little bit. > - The text rendering is slow if the text size is large > (not only if you zoom in to small text). What colour scheme are you using? The colours are hard-coded for now, and work nicely with the light colour scheme on my monitor. I've not really tried it, but I suspect on the black background, the old white dots grid may be more appealing. > I will do some more tests on real schematics. The schematics look really > great. Thanks! That was the intention ;). It should also mean we can do printing from within gschem using GTK's printing support (uses cairo) and a print-preview if we wanted. I can't see any easier way to allow printing of multilingual characters. There is a lot of smarts in cairo and pango to do that. Thanks for testing! -- Peter Clifton Electrical Engineering Division, Engineering Department, University of Cambridge, 9, JJ Thomson Avenue, Cambridge CB3 0FA Tel: +44 (0)7729 980173 - (No signal in the lab!) _______________________________________________ geda-dev mailing list [email protected] http://www.seul.org/cgi-bin/mailman/listinfo/geda-dev
