Re: [Gnu3dkit-dev] Event model

[Philippe C . D . Robert]

On Freitag, Oktober 11, 2002, at 06:50  Uhr, Matt Brandt wrote:
> I was looking at GLUTKit and I got to wondering why you wanted to 
> invent a new event model instead of using the standard cocoa event 
> model. I'm no authority on GNUStep but I would expect it to implement 
> the same event model as cocoa. It seems like we would be giving up 
> some commonality of interface with the rest of the foundation by 
> implementing different mouse and keyboard events.
>
> Is this something that changes in 0.4, or is there some deep reason 
> for doing things this way? It seems like for an application that has 
> some non-OpenGL windows as well as a G3DCamera that the programming 
> will suffer from the duality. I would rather see something that 
> implements the view model (G3DView?). For that matter, why not base 
> the camera on NSOpenGLView?

OK, let me explain the history a bit ...:-) The 3DKit was initially 
developed for a special application. By then it ran on Linux only, 
using the GNUstep frameworks. This was pre Mac OS X and there was no 
NSOpenGLView at all... Anyway, this app was also not a pure GNUstep 
app, it was only using the FoundationKit while the rendering was 
fullscreen, so I had to develop my own camera class - or better I 
designed the 0.2.x/0.3.x G3DKit in a way which enables the usage of any 
kind of backend, be it NSOpenGLView/AppKit, glut, SDL or direct X11 
rendering on X11 systems. This is done via separate libraries. Now 
every backend handles events differently, so I had to provide a nice OO 
wrapper for this as well, so that an app depending on the 3DKit was 
free to use any of the backends w/o changing its implementation...

In the 0.4 version the camera design will change completely similar to 
how you describe it. The camera will not be the view anymore ( as in 
NeXT's 3DKit as well ) but only be the controller which uses a channel 
( ie. the NSOpenGLView ) to render the scene. This provides more 
flexibility and a cleaner design, I think.

Thoughts? Does this answer your question?

-Phil
--
Philippe C.D. Robert
http://www.nice.ch/~phip