coLinux graphics support

Digital Infra, Inc.
Sun May 23 06:27:00 GMT 2004

Hello all.

We are making graphics support of coLinux. 
(coLinux is an emulator to run Linux as a Win32 app).
there are many ways -

1. coLinux FB
2. DirectFB/SDL
3. VNC
4. Cygwin/X
5. Mingw X

Each way has each charactaristics and pros and cons.
then, I need your opinion. probably you advocate Cygwin/X very much.
but it is ok. any information is welcome. anything is better than nothing.
of course, fair comparison is better.

                 Okajima, Jun. Digital Infra, Inc. Tokyo, Japan.

Detailed description:

coLinux FB:
same as Linux frame buffer but uses DirectX.
coLinux kernel allocates some pages on its "Pseudo Physical RAM" and DirectX
recognizes it as a frame buffer. then with DirectX hardware accelerated bitblt func,
the frame buffer is copied to a video RAM.
FYI, for windows, coLinux is recognized as a "big and funny AGP texture RAM".
good: generic. can be used many purpose without porting apps.
 - can utilize H/W acceleration well? for example, can we use bitblt func
to display scalable font cached on unusde area of video RAM?
 - Japananese support. this way needs to use Linux Japanese func, not Win32 one.
   but Linux is really poor in supporting Japanese.

Making direct path between DirectFB/SDL and DirectX FB. and by using
bitblt of Directx, it displays graphics.
good: I dont know. Probably coLinux FB is better.
      I think this is an alternative which we fail to run coLinux FB.

Using VNC server on coLinux side and you install VNC viewer on Windows.
then you make a virtual tcp connection between them.
good: you can connect from other machines. even on the mobile.
bad: can use only for X. maybe big overhead and little bit slower.
     Note: actually, as far as we tested, it is not slower. rather faster
           than Cygwin/X in some cases. why?

you dont need any description here ;).
good: orthodox. multiwindow(overlapped) mode.
      accommodate with Win32 API.
         - GDI for H/W acceleration.
         - Windows Japanese support, ex. TT renderer, TT font itself, etc.
         - better printing than just hitting "print screen" key.
      slower, buggy, huge, cygwin1.dll version dependency.
      As far as I know, it has no "reconnection" feature, which I mean
      when cygwin/X crashes, I can not get the session back even I restart Cygwin/X.
      Potentially it can use most part of Win32 Japanese support,
      currently only little stuff is implemented.
      lacks installer/admin utils.

good: no dependency of version number of cygwin1.dll.
bad: under construction. I dont know even detailed feature.
     it does not run on my PC currently. helps!

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