On Sat, 2002-08-03 at 06:54, Tomas Frydrych wrote:
> 
> Martin sent this to me privately, but I think this needs to go to the list, 
> it raises an important issue -- I hope Martin does not mind.
> 
> > HI Tomas,
> >  Think this through very very carefully. I'm not saying it can't be
> >  done
> > but it is not obvious to me right now. The issue is cursor dirt. If
> > the cursor is on (black) and a clearScreen is called over the cursor
> > then it gets set to white even though the internal state says it's
> > black. Then if the blink thread XOR's it now it will turn to black
> > even though the cursor's internal state says it should be white.
> > 
> > What is even worse is if the clear screen stops after clear the first
> > set of vertical pixels. Now the cursor is half white, half back and no
> > matter what, it looks funny and your guarenteed to get pixel dirt.
> > 
> > Getting rid of cursor dirt was a real pain, I worry that putting the
> > blink into a seperate thread will mess it all up.
> > 
> 
> I do not want the change the actual way the cursor behaves, only 
> put the timer which fires it into a separate thread so that it fires 
> every 500 ms and does not get blocked by some other timer. That's 
> all.
> 

I don't see how this would help. You'd have to turn the cursor off while
doing screen updates anyway (like doing spell checking). I think the
effect would be much the same.

> I had a look at Mike's cursor class; it looks very good, but it would 
> mean to rip the whole cursor code up, and that's not something I 
> personnally want to do just now.
> 
> Tomas


Reply via email to