[Kde-games-devel] Chess game for KDE4

[Luciano Montanaro]

On venerdì 04 dicembre 2009, Ian Wadham wrote:

> 
> Just to remind everybody ... there are three reasons to prefer KGameCanvas
> over QGV ... speed, speed and speed.  I do not know if QGV is yet fast
>  enough all the time to run KGoldrunner.  It always was fast enough most of
>  the time, but you cannot tolerate hiccups of a substantial fraction of a
>  second, while QGV decides to go off and do some housekeeping, if your game
>  is running to a 50 msec timescale.
> 
> Similar concerns might apply to Bomber, KBounce and KBreakout, though
> perhaps not to KBattleship and KMahjongg ... and certainly not to Chess.
> 

> I do not know if I will ever drum up the enthusiasm to benchmark QGV
> all over again, let alone re-program KGoldrunner using QGV.
> 
> If KGCanvas were ever to depart, I might consider going to 2-D OpenGL.
> I found out when writing Kubrick that OpenGL is blisteringly fast compared
> to any offerings based on Qt (such as QGV and KGCanvas).

Hi Ian, I remember the problem wit QGV and Qt4.0. And yes, OpenGL is fast. 
It's not easy to use, though.

However... All of Qt rendering operations can already be done through OpenGL, 
and performancew sill improve over time. OpenGLES is part of all embedded 
stacks, or it is going to be soon, so the feature is going to be exploited by 
Qt.

So I think KGameCanvas has served us well, it will continue to do so for our 
existing games, but for new development I'd check QGraphicsView first.
An additional point is that the animation and graphics effects infrastructure 
is layered on top of that (Well, animation links objects attributes to points 
on a timeline, but...).


> I think that is
> why OpenGL is behind Qt paint engine and composite graphics trickery in
> KDE 4 windows.
> 

Oh, that's the point for sure. Hardware has focused on OpenGL graphics 
acceleration for at least 15 years. Two-D graphics acceleration is frozen 
since... let's say 1990. Speed is a bit better than those days, but no 
improvement has gone that direction. And there is little point in doing that, 
because if 3d is so fast, it can handle 2d as well as a degenerate case.

So I think the future is with OpenGL... I just hope I will not have to wait 
much longer to have OpenGL working on my computer. It always looks like good 
3d support in Linux is just one year away... 

Ciao,
Luciano



-- 
Luciano Montanaro //
                \X/ mikelima at cirulla.net