Path: utzoo!utgpu!news-server.csri.toronto.edu!cs.utexas.edu!rutgers!faatcrl!jprad From: jprad@faatcrl.UUCP (Jack Radigan) Newsgroups: comp.sys.amiga.datacomm Subject: Re: Jr-Comm Message-ID: <1472@faatcrl.UUCP> Date: 18 Jun 91 14:14:01 GMT References: <676276570.1@kcufgat.fidonet> <231b3678.676527511@fergvax> <1991Jun16.020152.2331@cccan.uucp> Organization: FAA Technical Center, Atlantic City NJ Lines: 36 entity@cccan.uucp (Cybernetworx) writes: >In article <231b3678.676527511@fergvax> 231b3678@fergvax.unl.edu (Phil Dietz) writes: >Actually, it COULD be done at speeds above 2400 as well. There's a few >solutions that jack could consider. One would be to use direct blitter >access through the hardware for the screens (of course it won't conflict >with other programs blitter use because he would make sure blitter busy >wasn't set. More importantly, programs running in the background would >probably not require much blitter use, since it is generally used for >screen updates etc) In addition, by using an interleaved bitmap screen, >he would also get rid of that annoying flicker since all bitplanes are >moved in one blit. (it's also considerably faster doing blits this way) >An optimal solution might be to avoid the blitter altogether for moving >the screen, and just use a wraparound bitmap by using the copper to do >all the work. The blitter/68000 could be used simply for putting the >characters on the bitmap. This would definitely be the fastest solution. A Copper list is probably the best way to go, performance-wise, since the major thing here is to keep chip DMA contention down to a bare minumim because the cpu needs some chip time in order to access the serial port which is in chip address space. An interleaved bitmap is also viable, but less so, since I have to be able to do a quick de-dice of the screen before I can allow Intuition to put up its menus. I'd think that a Copper list that is oriented to text lines would be easier to do than an interleaved bitmap. Also, the text routines would need to be customized with an interleaved bitmap, right? Since WB2.0 speeds things up a good bit already, I think that this is less of a demand than it would have been under 1.3. Additional comments welcome... -jack-