[wxruby-users] Transparent line in Frame

[Alex Fenton]

Andreas Warberg wrote:
> I want to draw transparent lines in a Frame. I have the following setup
> but my lines are not transparent.
The standard DC doesn't support transparency (except on OS X I think). 
But you can instead use wxGraphicsContext which fully supports 
transparency, antialiasing and other advanced drawing tools like splines 
and transforms. You create one from an ordinary DC like this:

paint.do | dc |
  gdc = Wx::GraphicsContext.create(dc)
  gdc.stroke_line(0, 0, 500, 500)
  # etc
end

Unfortunately the wxWidgets developers decided to make the API to 
GraphicsContext different to DC, but the results are worth it for 
graphical apps.

alex