billk@crash.UUCP (02/13/87)
Has anyone else seen the program, "Blitz" ???
Ok, now does anyone want to speculate on how it does what it does so fast?
I have a few speculations of my own...
In the "Fast Key" mode, Blitz seems to be checking for key UP and DOWN codes,
rather than the key itself. So, I held down the down-arrow key and began
whizzing through a long file. Then, I pressed the menu-button on the mouse.
The text of my file kept whizzing past me even though I was holding down the
menu-button. I went and pulled down some menus. As soon as the menus formed,
they were whizzed right off the screen along with the rest of the text that
was still whizzing by.
This kinda confirmed my suspicions that Blitz wasn't emitting text through any
of the Amiga routines that know about LockLayers(). My only guess is that
Blitz is getting the pointer to the Font data itself and just making the
blitter blit it.
Since Blitz is set up in it's own screen, I suppose doing this would not be
a super-hard thing to do.
Oh, for those of you who haven't seen Blitz:
It took me 21 seconds to TYPE a four page file from DOS. With Blitz, you can
run through a 104 page file in 26 seconds! (I did!) Wow! That's pretty cool.
Does anyone want to comment on my speculations about how Blitz works? Want to
add your own? Please do.
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
Bill Kelly "If at first you don't succeed, forget it!"
UUCP: {akgua, hplabs!hp-sdd, sdcsvax}!crash!pnet01!billk
ARPA: crash!pnet01!billk@nosc
INET: billk@pnet01.CTS.COM
USPS: 2507 Caminito La Paz
La Jolla, CA 92037
FONE: (619) 454-1307
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~upl@puff.UUCP (02/15/87)
In article <791@crash.CTS.COM>, billk@pnet01.CTS.COM (Bill Kelly) writes: > Has anyone else seen the program, "Blitz" ??? Yes. > Ok, now does anyone want to speculate on how it does what it does so fast? > I have a few speculations of my own... So do I. > In the "Fast Key" mode, Blitz seems to be checking for key UP and DOWN codes, > rather than the key itself. So, I held down the down-arrow key and began It does this in normal mode, too. > whizzing through a long file. Then, I pressed the menu-button on the mouse. > The text of my file kept whizzing past me even though I was holding down the > menu-button. I went and pulled down some menus. As soon as the menus formed, > they were whizzed right off the screen along with the rest of the text that > was still whizzing by. > > This kinda confirmed my suspicions that Blitz wasn't emitting text through any > of the Amiga routines that know about LockLayers(). My only guess is that Not quite. In normal mode, it is using ScrollRaster() to scroll the WINDOW's RastPort, which is in a layer, and is Lock'ed when menus appear. In 'fast key' mode, he's probably using BltBitMap() to scroll, thus ignoring layers and being a little lower-level and faster. Looking at the executable file, it looks like it was written in assembler, too. And it has the text 'topaz.font', which indicates that it gets the font data. > Blitz is getting the pointer to the Font data itself and just making the > blitter blit it. This is my thought, or even (yech!) using the 68000 which, for small data structures (characters), is probably faster than the blitter. > Since Blitz is set up in it's own screen, I suppose doing this would not be > a super-hard thing to do. > > Oh, for those of you who haven't seen Blitz: > > It took me 21 seconds to TYPE a four page file from DOS. With Blitz, you can > run through a 104 page file in 26 seconds! (I did!) Wow! That's pretty cool. My sentiments exactly. I may incorporate something similar in my terminal program, as using Text(), I can't quite get 9600 baud to the screen. > Does anyone want to comment on my speculations about how Blitz works? Want to > add your own? Please do. I did. I'm sorry, but I don't currently have a mailing address. Please don't mail this account. If you must get something to me, try: {caip, harvard, allegra, ihnp4}!uwvax!puff!uhura!scotty!avery This may work soon, but uhura is currently down. Aaron Avery