While Replay is perfectly happy to run in a machine with no additional
information, performance can be improved by setting various system variables
for it. Full documentation is in !ARMovie.Documents.ProgIf. Recent versions of
this file can be found on OfficeAuto.Replay.

(a) if there's a lot of spare memory, then setting ARMovie$ColourMapMax is a
good idea. Even playing movies in the same colour space can lead to more than
one colour map being used. I'd recommend leaving it unset on 4MByte machines
(one colour map only) or setting it to 1 on bigger ones (2 colour maps).
Obviously Replay won't use the memory unless a movie is played! If there's a
timer watchdog, or memory is exhausted for some other task than Replay, it
would be worth running the program <ARMovie$Dir>.MovingLine.ColourMap.Delete to
reclaim colour map memory. If -multi is going to be used, then a non zero
setting may be essential (in order to play two movies with different colour
maps)

(b) if the machine is linked to its file server by a slow link, its worth
setting ARMovie$FileTime, since the machine can then compute some colour tables
algorithmically without file reference at all. An hourglass counter will spin
while it does it the first time - after that the information is cached. At the
time of writing this only affects operation at 8bpp with the standard RISC OS
palette.

(c) One really should set ARMovie$MachinePixels, especially if large movies
are to be played. The value depends on the machine's memory performance, so
may need some work for a particular machine. 1500000 is right for a RiscPC
700, 1000000 is about right for an ARM7500 in TV mode, 3000000 is sort of OK
for a StrongARM RiscPC. Otherwise measurements will need to be taken.

(d) Setting ARMovie$Interpolate is also a good move. Suitable values for a
RiscPC 700 are 400000,700000, for a StrongARM RiscPC 1000000,1500000 and
256000,512000 for an ARM7500.

(e) If big mode is to be used ARMovie$PrefBigMode is a jolly good thing to set!
For a RiscPC 700 with VRAM and a monitor
x480y352c32kex1ey1;x640y480c32kex1ey1;x480y352c32kex0ey0 is a good value.

(f) If 16 colour modes are in use, ARMovie$4Colour may be of interest,
particularly if a non-standard palette is in use (the ordinary 16 colours in
RISC OS don't look very good since there's no magenta).

(g) Setting BASIC$Crunch (e.g. to .) may be a helpful move. The main components
of Replay are compressed already, but smaller components are not and this helps
them run in less memory (and somewhat faster).

(h) More colours on display helps! Picture quality will probably only be
marginal with 256 colours, reasonable with 32768 colours and right with 16
million.

--Sophie

Chief Scientist at Acorn Network Computing: ddi Cambridge (UK) 1223 518550

| Words are like rocks: they weigh you down.          |
| If birds could speak, they wouldn't be able to fly. |

