Re: [gsl-dev] GTK+ v FLTK

[Edward Peterlin <ed dashboardbuddha com>]

> I believe people have looked at the 'vcl using gtk theme engine/drawing
> api' in the past, I believe one could do it now, and not wait for
> toolkit2. It would give you a correctly theming and drawing but not 
> really
> gtk looking (except for small details like widget looks) app.

Examine the approach of Neo:

http://www.neooffice.org

And yes, you will need to look at the source if you want to move beyond 
the binary and the "it's drawing the Aqua buttons but without changing 
VCL and how is it doing it?" stage.  It adds in an additional 
abstraction to the OutputDevice class for drawing requests for full 
controls on top of the standard geometric primitives of a functional 
drawing layer.  E.g., it is possible for code to request "hey you, draw 
a button with the following label here" and (alebit with a little 
better architecting) it draws the button in whatever underlying 
mechanism it wants, be it through a native widget, native bitmap draw 
requests (current approach in Neo), or the existing VCL abstraction.  
Through using adaptations of this API it's incredibly easy to provide 
platform specific widget appearances, swappable widget set appearances 
through swapping libvcl on installation or choosing between different 
OutputDevice implementations at runtime.

There is absolutely NO reason we need to move to GTK or ANY OTHER 
"cross-platform" toolkit for the sheer purpose of drawing buttons in 
the appearance of a specific platform and widget set.  The Neo 
prototype proves this point in a rather self-evident fashion of OOo 
running on top of a completely different widget set from its core 
implementation, not to mention pure native widgets in an AWT peer 
similar fashion for menus.

ed