Open GoogleCodeExporter opened 9 years ago
Some initial testing shows that enabling transparencies (alpha blending) in
GeoDa is possible. However, alpha blending is only available through the
wxGraphicsContext (cairo) which is only native to OSX. Initial testing shows a
minimal slowdown for OSX, but for Windows and Unix there is a massive slowdown.
More investigation is needed.
Original comment by mmcc...@gmail.com
on 7 Apr 2014 at 11:57
cross-platform issues may need new assessment with new wx version
Original comment by lanse...@gmail.com
on 25 Jun 2015 at 2:19
first, there is no performance issue of transparency on mac osx.
second, to support transparency on windows, wxGraphicsDeviceContext has to be
used, and the implementation of wxGrap... is slower on windows platform.
thrid: the performance of wxGraph is about 1.5x slower on windows than on mac
osx.
here is a proposed solution: the transparency support will be enabled on
windows only when user select to draw basemap.
fix is proposed in ci 3687.
fix will be in build >= 1.7.37
Original comment by lixun...@gmail.com
on 7 Jul 2015 at 6:02
wxGraphicsDeviceContext on Windows was typically about 20x slower according to
my testing. However, there was an effort last year by a student on a Google
Summer of Code scholarship to fix. The next version of wxWidgets, (3.0.4 or
3.1?) should have these changes.
The wxGraphicsDeviceContext has been the native implementation on Mac for years
now and therefore supports all of the advanced/modern 2D rendering capabilities
on the Mac with now slowdown. This is why I used both wxDC and wxGC on the
backend depending on the OS. Hopefully only wxGC will be needed in the future!
Good luck :)
Original comment by mmcc...@gmail.com
on 7 Jul 2015 at 6:14
the performance of wxGC is about 15x slower from another test using big dataset.
So the fix logic is change to: transparency will be manipulated via raw bitmap
data to avoid any performance issue on different platforms
fix is proposed in ci 3688
fix will be in 1.7.37
Original comment by lixun...@gmail.com
on 8 Jul 2015 at 7:53
Original issue reported on code.google.com by
mmcc...@gmail.com
on 4 Apr 2014 at 5:44