[Kde-games-devel] Low framerate in Kdiamond

[Stefan Majewsky]

On Sunday 25 May 2008 15:22:44 Mauricio Piacentini wrote:
> Running at 1200x800, in a VMWare environment, the game is definately
> playable. But in 12x12 mode I can see the hint of a hiccup when the new
> pieces are falling, so what Eugene is seeing is probably this, but made
> worse by something in his hardware or software environment.
> I would not say it is a ship stopper, but something to be investigated
> in more detail. It is probably another manifestation of our magic power,
> the one that reveals subtle issues in QGV that no one has seen before.
> This one might actually be solvable by playing with the optimization
> flags. Eugene, do you have qt4.4?

I have investigated the effect of KWin compositing on my small notebook. When 
KWin4's compositing (aka "desktop effects") are activated and the game is at 
fullscreen resoultion (i.e. about 600x600), the lags are noticeable, the 
animation's start is jumpy. However, when I turn off compositing, the lags are 
totally gone.

Another idea I had is "setViewport(new QGLWidget)" for my QGraphicsView. That 
did also solve the problem totally, but I had to kill Plasma to make KDiamond 
playable because Plasma repainted even if obscured by the KDiamond window. 
(That is definitely a Plasma bug, because I notice the same behavior with my 
OpenGL-powered screensaver.)

An option (at least for me) could be the introduction of a menu point "Use 
OpenGL for drawing" which activates this option, but sadly are we in feature 
freeze and I'm not sure if the jumpy animations can be considered a bug that 
legitimates this change.

Good night
Stefan