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[REBOL] Smooth scrolling. What's requiered? Jim? (was) Multimedia quality (was)

From: petr:krenzelok:trz:cz at: 26-Aug-2000 13:13

[allen--rebolforces--com] wrote:
> ----- Original Message ----- > From: <[kolla--nvg--ntnu--no]> > To: <[list--rebol--com]> > Sent: Saturday, August 26, 2000 11:38 AM > Subject: [REBOL] Re: Multimedia quality (was) One disk OS + REBOL Re:(8) > > > On Fri, 25 Aug 2000 [holger--rebol--com] wrote: > > > > > What makes REBOL/View relatively slow on Amigas with the native graphics > > > chipset is the necessary chunky-to-planar conversion. We are using > > > optimized Assembler code for that, but it is still a bottleneck. On > > > Amigas with graphics boards REBOL/View is reasonably fast (often > > > faster than under Unix/X running on the same hardware). > > > > But still dog slow, even on my [P3--650MHz] linux box I find it annoyingly > > slow, and I often end up clicking on buttons twice, or more. > > This is interesting, I haven't seen anyone mention speed problems on Linux > before. > I must set up a linux version to test on. > I've tested View on my old faithful Celeron 333, under Win 98, Win2000, BeOS > and Amiga (under emulation). > > My general observations of platform differences... > The Amiga was slow, but it sounds like it was running faster under emulation > than the older native machines. Win platforms speed is quite good, except > for iterated faces and large area scrolling. Timer events seems have a > better resolution on Win2000 than Win98. > BeOS has the fastest smoothest scrolling of all of the above. > Font rendering/display seems to be best/clearest on Windows. >
OK, I am just testing /View on my old P133. Iterated faces (mainly lists) are nearly unusable. Button hilighting is very nice even on that crappy hw :-) It's just because it is cached or so we were told. We were also told there will be some kind of caching (saving the background) for transparent faces. But if I understand it correctly, the purpose of iterated display is to save the memory (in other case imagine having all the lines of list display having in memory). But - with such dynamic display, is it possible to cache it? It would cost us additional memory. Would it be even technically possible to refer back to such cached data, as lists are just generated by function call? Just a small note: However, there are times where iterated display is not desired/required. During beta1 stage I developed an example of file manager, using grid of faces. ( http://www.rebol.cz/~can/rebol-view/image2.jpg ). Performance was not all that bad ... Well, now back to the topic - scrolling. I am an amigan and so I came to PC area from the world of very smooth scrolling. Every PC man should go and look at original screen dragging on Amiga. Smooth even on 14Mhz Amiga 500 (or was it even 7 Mhz? :-) IIRC it was hardware supported feature, but not sure. Then I came to Windows. Disaster. Even today on such much powerfull machines. Then I saw Scala on PC - quite good smooth performance. Is it because Scala uses those DirectXY features? :-) I also noticed MS doing something about scrolling, as their IE scrolls much better than Netscape. It has to have something to do with their internal Windows routines, as the same kind of scrolling is used in Windows explorer (tree view). Can we have any use of it? As I remember Michal Kracik stating his boing ball demo performed much smoothly under WinNT I have following question. Is smoothness of scrolling something what can't be achieved thru all /View platforms by some own routines? Because if it's not dependent upon what particular OS offers us, please implement it, as people often judge product upon what they see ... Cheers, -pekr-