Shuhao Wu twisted the bytes to say:
Shuhao> Another question is how do you enabled efficient erasing? How is the Shuhao> line segments stored so they can be efficiently looked up for erasing? I have the feeling you are writing an application to do pen annotations :) --dmg Shuhao> Thanks, Shuhao> Shuhao Shuhao> On 10/01/2014 05:00 PM, Denis Auroux wrote: >> On 10/01/2014 05:20 PM, Shuhao Wu wrote: >>> I'm also impressed by the fact that the anti aliasing looks very good. I >>> assume this is handled by gnome >> >> Yes -- by libgnomecanvas specifically (with the help of libart_lgpl >> again). Xournal doesn't do any antialiasing of its own. >> >> Libgnomecanvas has some annoying issues (no longer well-maintained, a >> few bugs, not compatible with gtk3, ...) but it does have >> some unique features like the high display quality (the other one you >> might not notice is performance -- xournal isn't always as fast as one >> would like, but with a less optimized display library it would be worse. >> Apparently the GTK3 canvas widgets that Daniel tried to use for his gtk3 >> port of xournal are much slower. A xournal document typically has >> hundreds of thousands of line segments and, while that's nothing >> compared to modern video games and other 3d stuff, it's enough to choke >> to death libraries that were written with business software in mind -- >> display refresh needs to think carefully about what exactly needs to be >> redrawn.) >> >>> and the fact that the line segment is so small? (0.3px?) >> >> In real life if you write quickly the line segments are not that short >> -- my tablet reports motions quickly and if the pen is moved slowly the >> line segments end up indeed being very short, but when drawing longer >> lines quickly the successive points can be 5-10 pixels apart (but what >> helps is that each point has a fractional position which is much more >> accurate than having just integer pixel coordinates). >> >>> Furthermore is pressure sensitivity data recorded per line segment? >> >> Yes, when pressure sensitivity is on, each line segment has its own >> pressure value and hence its own thickness. >> >> Denis >> Shuhao> ------------------------------------------------------------------------------ Shuhao> Meet PCI DSS 3.0 Compliance Requirements with EventLog Analyzer Shuhao> Achieve PCI DSS 3.0 Compliant Status with Out-of-the-box PCI DSS Reports Shuhao> Are you Audit-Ready for PCI DSS 3.0 Compliance? Download White paper Shuhao> Comply to PCI DSS 3.0 Requirement 10 and 11.5 with EventLog Analyzer Shuhao> http://pubads.g.doubleclick.net/gampad/clk?id=154622311&iu=/4140/ostg.clktrk Shuhao> _______________________________________________ Shuhao> Xournal-devel mailing list Shuhao> Xournal-devel@lists.sourceforge.net Shuhao> https://lists.sourceforge.net/lists/listinfo/xournal-devel -- Daniel M. German "A mind of moderate capacity which closely pursues one study must infallibly arrive Mary Shilley -> at great proficiency in that study." http://turingmachine.org/ http://silvernegative.com/ dmg (at) uvic (dot) ca replace (at) with @ and (dot) with . ------------------------------------------------------------------------------ Comprehensive Server Monitoring with Site24x7. Monitor 10 servers for $9/Month. Get alerted through email, SMS, voice calls or mobile push notifications. Take corrective actions from your mobile device. http://p.sf.net/sfu/Zoho _______________________________________________ Xournal-devel mailing list Xournal-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/xournal-devel
