Home » Archimedes archive » Acorn User » AU 1997-12.adf » Regulars » StarInfo/SpencerR/!Linez/!Help
StarInfo/SpencerR/!Linez/!Help
This website contains an archive of files for the Acorn Electron, BBC Micro, Acorn Archimedes, Commodore 16 and Commodore 64 computers, which Dominic Ford has rescued from his private collection of floppy disks and cassettes.
Some of these files were originally commercial releases in the 1980s and 1990s, but they are now widely available online. I assume that copyright over them is no longer being asserted. If you own the copyright and would like files to be removed, please contact me.
| Tape/disk: | Home » Archimedes archive » Acorn User » AU 1997-12.adf » Regulars |
| Filename: | StarInfo/SpencerR/!Linez/!Help |
| Read OK: | ✔ |
| File size: | 1F10 bytes |
| Load address: | 0000 |
| Exec address: | 0000 |
File contents
> !Linez.!Help
LINEZ : A USER-CONFIGURABLE DESKTOP SCREENSAVER
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
INTRODUCTION
Linez is a desktop front-ended screensaver which bounces lines around the
screen, fading them from one colour to another. The lines can either be
straight or curved (bezier) and for speed the screensaver code itself is
written in pure ARM assembler. This program requires 32k to execute.
This screensaver does not, however, work with the RISC OS screenblanker
utility so this should be turned off. Also, in multitasking mode, naughty
programs that use direct screen access without checking for screen output
disabling, like Zap`s flashing cursor or an active taskwindow, can cause
wierd little bits to appear on the screen in odd places.
The basics are that clicking SELECT on the application on the iconbar
icon opens the configuration window (which should be self-explanatory) and
ADJUST starts the sceensaver (which usually has a delay time of 30 seconds).
By default the screensaver runs in the current desktop mode. Move the mouse
or press SHIFT to return to the desktop.
Things can get REALLY fun when you have say five copies of the screensaver
multitasking together - they will all start at the same time! For best
results don`t use reflection when using multiple copies.
LICENCE
This program is FREEWARE so may be used and distributed freely without
money changing hands (other than disc prices for PD libraries etc.) as long
as it remains complete and unaltered.
DETAILED INSTRUCTIONS
Double-click on the icon in the filer window (why I am bothering to say
this I have no idea...) and the program will install itself on the icon bar.
Clicking MENU on the icon bar icon brings up a menu with three entries:
Info, Help �, Quit. Info leads to an information box thingy (yes I know
`Totally amazing screensaver` sounds really pretentious but no one takes
these purpose fields seriously anyway). Help�� (note use of really cool
ellipsis) loads this particular file into the nearest friendly text editor.
Quit terminates execution of the proggy (not that you`d want to do that).
SELECT opens the configuration window as mentioned before. The fields are
described below. Time Delay sets how long a period of desktop inactivity is
required to trigger the screensaver. There is the option to set whether or
not the screensaver multitasks between drawing each line. Note that
multitasking can slow it down a LOT especially if file operations are going
on while it`s trying to draw lines all over the screen. If multiple copies
are loaded then only ones with the multitasking option set will start up.
Screen mode allows you to specify the resolution/colour depth the
screensaver operates in. Desktop mode uses the current desktop mode. Mode
number allows RISC OS 3.1 users to specify a mode number; a 256 colour one
is preferable like mode 15 (CGA) or mode 28 (VGA). Mode string allows RISC
OS 3.5+ users to specify resolution and colour depth exactly (it doesn`t
work on RISC OS 3.1 so don`t bother to try). If the mode number is
unavailable/invalid then the current desktop mode is used. If the mode
string is unsuitable then you`ll get an error message - but most RPC/A7000
users will probably use the Desktop mode option as they`ll be running a 256+
colour mode anyway. The visible advantage of 32K colours over 256 is small
and of 16M over 32K even less! Incidentally, a CMYK palette is used in a 4
colour mode which looks better than RGB IMHO, and a custom one used in a 16
colour mode.
It is possible to set whether straight or bezier lines are used, and the
quality of the bezier lines. The number 2 raised to the power quality is how
many straight lines make up the bezier curve - with quality 5 there are 32
for example. The delay between lines is measured in centiseconds. If the
lines take longer to draw than the delay then this delay time is ignored.
The points for one line only are calculated but these can be reflected to
produce interesting effects. Best results are reflecting in the line y=-x or
all three. Maximum velocity is measured in OS units per second (a VGA screen
is 1280 by 960 OS units) and maximum acceleration in 1/16ths of an OS unit
per second squared (!) Colour fading is based on an RGB colour cube:
intensities 64-255 are used for the red, green and blue components. Acc
change every and Fade change every is the average number of lines between a
change in the acceleration or fading rate.
The Demo button allows you to view the effects of any changes without
storing them and Cancel will reset any values you have not OK`d. OK and Save
both store the changes, but as you might expect Save creates a file called
Config inside the application ready for when you reload. Click ADJUST on any
of these buttons and the window stays open.
If you click ADJUST on the iconbar icon the screensaver is started
immediately but unlike pressing Demo any un-OK`d changes are not taken into
account. It in effect shortens the delay time to zero. Any movement of the
mouse or keypress will return you to the desktop, however I recommend you
move mouse or press SHIFT in multitasking mode so you don`t end up typing in
stuff where you didn`t want it.
A FEW IDEAS
Here are a few values to give you a few ideas for experimenting with. They
were obtained using MODE 28, delay time of 4 and bezier line quality of 5 in
singletasking mode on my trusty A3010.
*-----------------------------------------------------------------------*
| Type of line | STRAIGHT | BEZIER |
|-------------------+-------------------------+-------------------------|
| Number of lines | 25 | 50 | 35 | 40 | 70 | 10 | 20 | 15 |
| Reflection | all | none | x | y=-x | none | y | y=-x | all |
| Max velocity | 16 | 32 | 24 | 20 | 16 | 64 | 28 | 20 |
| Max acceleration | 32 | 4 | 8 | 0 | 2 | 16 | 8 | 4 |
| Max fade | 32 | 8 | 20 | 12 | 4 | 64 | 24 | 20 |
| Acc change every | 50 | 100 | 200 | 500 | 100 | 10 | 160 | 15 |
| Fade change every | 100 | 250 | 75 | 120 | 50 | 50 | 80 | 60 |
*-----------------------------------------------------------------------*
HOW IT WORKS
Each straight line requires two reference points (each end in other words)
and each bezier curve needs four. Each point has both an x and y position,
velocity and acceleration. Every frame, the velocities are added to the
positions and the accelerations to the velocities. The illusion of movement
is given by blanking out one of the previous lines leaving the correct
number still on screen. The colour is stored as 24-bit RGB with the red,
green and blue elements changing at a constant rate. The colour change rates
and accelerations are changed to new random values every so often. The
centre of the screen is set to be the origin so reflection is simply done by
changing the sign of the x, y or both co-ordinates and drawing the
line/curve again. The colour is set using the ColourTrans module to pick the
closest match and dithering is used.
SPEED IMPROVEMENTS (ARM2/250)
The calls to the operating system to draw the lines can be made MUCH
faster on RISC OS 3.1 by speeding up the ROM`s. To do this you need to type
SYS�"OS_UpdateMEMC",160,240 at the BASIC prompt (or create a BASIC program
and run it). *RMFaster ColourTrans may have some effect. Alternatively, to
increase speed try using less reflection and lower bezier line quality and
not trying to multitask 99 copies together - or buy a RiscPC!
THE AUTHOR
A humble penniless physics student slaving away over his Arc for hours on
end when there are far more exciting things on offer ....
Richard Spencer physrs@leeds.ac.uk (until May 2001)
Mortain House
Bodington Hall
Otley Road
LEEDS
LS16 5PT
(until June 1998)
You know what to do!
00000000 3e 20 21 4c 69 6e 65 7a 2e 21 48 65 6c 70 0a 0a |> !Linez.!Help..| 00000010 20 20 20 20 20 20 20 20 20 20 20 20 20 4c 49 4e | LIN| 00000020 45 5a 20 3a 20 41 20 55 53 45 52 2d 43 4f 4e 46 |EZ : A USER-CONF| 00000030 49 47 55 52 41 42 4c 45 20 44 45 53 4b 54 4f 50 |IGURABLE DESKTOP| 00000040 20 53 43 52 45 45 4e 53 41 56 45 52 0a 20 20 20 | SCREENSAVER. | 00000050 20 20 20 20 20 20 20 20 20 20 7e 7e 7e 7e 7e 7e | ~~~~~~| 00000060 7e 7e 7e 7e 7e 7e 7e 7e 7e 7e 7e 7e 7e 7e 7e 7e |~~~~~~~~~~~~~~~~| * 00000080 7e 7e 7e 7e 7e 7e 7e 7e 7e 0a 20 20 20 20 20 20 |~~~~~~~~~. | 00000090 20 20 20 20 20 20 20 0a 49 4e 54 52 4f 44 55 43 | .INTRODUC| 000000a0 54 49 4f 4e 0a 0a 20 20 4c 69 6e 65 7a 20 69 73 |TION.. Linez is| 000000b0 20 61 20 64 65 73 6b 74 6f 70 20 66 72 6f 6e 74 | a desktop front| 000000c0 2d 65 6e 64 65 64 20 73 63 72 65 65 6e 73 61 76 |-ended screensav| 000000d0 65 72 20 77 68 69 63 68 20 62 6f 75 6e 63 65 73 |er which bounces| 000000e0 20 6c 69 6e 65 73 20 61 72 6f 75 6e 64 20 74 68 | lines around th| 000000f0 65 0a 73 63 72 65 65 6e 2c 20 66 61 64 69 6e 67 |e.screen, fading| 00000100 20 74 68 65 6d 20 66 72 6f 6d 20 6f 6e 65 20 63 | them from one c| 00000110 6f 6c 6f 75 72 20 74 6f 20 61 6e 6f 74 68 65 72 |olour to another| 00000120 2e 20 54 68 65 20 6c 69 6e 65 73 20 63 61 6e 20 |. The lines can | 00000130 65 69 74 68 65 72 20 62 65 0a 73 74 72 61 69 67 |either be.straig| 00000140 68 74 20 6f 72 20 63 75 72 76 65 64 20 28 62 65 |ht or curved (be| 00000150 7a 69 65 72 29 20 61 6e 64 20 66 6f 72 20 73 70 |zier) and for sp| 00000160 65 65 64 20 74 68 65 20 73 63 72 65 65 6e 73 61 |eed the screensa| 00000170 76 65 72 20 63 6f 64 65 20 69 74 73 65 6c 66 20 |ver code itself | 00000180 69 73 0a 77 72 69 74 74 65 6e 20 69 6e 20 70 75 |is.written in pu| 00000190 72 65 20 41 52 4d 20 61 73 73 65 6d 62 6c 65 72 |re ARM assembler| 000001a0 2e 20 54 68 69 73 20 70 72 6f 67 72 61 6d 20 72 |. This program r| 000001b0 65 71 75 69 72 65 73 20 33 32 6b 20 74 6f 20 65 |equires 32k to e| 000001c0 78 65 63 75 74 65 2e 0a 0a 20 20 54 68 69 73 20 |xecute... This | 000001d0 73 63 72 65 65 6e 73 61 76 65 72 20 64 6f 65 73 |screensaver does| 000001e0 20 6e 6f 74 2c 20 68 6f 77 65 76 65 72 2c 20 77 | not, however, w| 000001f0 6f 72 6b 20 77 69 74 68 20 74 68 65 20 52 49 53 |ork with the RIS| 00000200 43 20 4f 53 20 73 63 72 65 65 6e 62 6c 61 6e 6b |C OS screenblank| 00000210 65 72 0a 75 74 69 6c 69 74 79 20 73 6f 20 74 68 |er.utility so th| 00000220 69 73 20 73 68 6f 75 6c 64 20 62 65 20 74 75 72 |is should be tur| 00000230 6e 65 64 20 6f 66 66 2e 20 41 6c 73 6f 2c 20 69 |ned off. Also, i| 00000240 6e 20 6d 75 6c 74 69 74 61 73 6b 69 6e 67 20 6d |n multitasking m| 00000250 6f 64 65 2c 20 6e 61 75 67 68 74 79 0a 70 72 6f |ode, naughty.pro| 00000260 67 72 61 6d 73 20 74 68 61 74 20 75 73 65 20 64 |grams that use d| 00000270 69 72 65 63 74 20 73 63 72 65 65 6e 20 61 63 63 |irect screen acc| 00000280 65 73 73 20 77 69 74 68 6f 75 74 20 63 68 65 63 |ess without chec| 00000290 6b 69 6e 67 20 66 6f 72 20 73 63 72 65 65 6e 20 |king for screen | 000002a0 6f 75 74 70 75 74 0a 64 69 73 61 62 6c 69 6e 67 |output.disabling| 000002b0 2c 20 6c 69 6b 65 20 5a 61 70 60 73 20 66 6c 61 |, like Zap`s fla| 000002c0 73 68 69 6e 67 20 63 75 72 73 6f 72 20 6f 72 20 |shing cursor or | 000002d0 61 6e 20 61 63 74 69 76 65 20 74 61 73 6b 77 69 |an active taskwi| 000002e0 6e 64 6f 77 2c 20 63 61 6e 20 63 61 75 73 65 0a |ndow, can cause.| 000002f0 77 69 65 72 64 20 6c 69 74 74 6c 65 20 62 69 74 |wierd little bit| 00000300 73 20 74 6f 20 61 70 70 65 61 72 20 6f 6e 20 74 |s to appear on t| 00000310 68 65 20 73 63 72 65 65 6e 20 69 6e 20 6f 64 64 |he screen in odd| 00000320 20 70 6c 61 63 65 73 2e 0a 0a 20 20 54 68 65 20 | places... The | 00000330 62 61 73 69 63 73 20 61 72 65 20 74 68 61 74 20 |basics are that | 00000340 63 6c 69 63 6b 69 6e 67 20 53 45 4c 45 43 54 20 |clicking SELECT | 00000350 6f 6e 20 74 68 65 20 61 70 70 6c 69 63 61 74 69 |on the applicati| 00000360 6f 6e 20 6f 6e 20 74 68 65 20 69 63 6f 6e 62 61 |on on the iconba| 00000370 72 0a 69 63 6f 6e 20 6f 70 65 6e 73 20 74 68 65 |r.icon opens the| 00000380 20 63 6f 6e 66 69 67 75 72 61 74 69 6f 6e 20 77 | configuration w| 00000390 69 6e 64 6f 77 20 28 77 68 69 63 68 20 73 68 6f |indow (which sho| 000003a0 75 6c 64 20 62 65 20 73 65 6c 66 2d 65 78 70 6c |uld be self-expl| 000003b0 61 6e 61 74 6f 72 79 29 20 61 6e 64 0a 41 44 4a |anatory) and.ADJ| 000003c0 55 53 54 20 73 74 61 72 74 73 20 74 68 65 20 73 |UST starts the s| 000003d0 63 65 65 6e 73 61 76 65 72 20 28 77 68 69 63 68 |ceensaver (which| 000003e0 20 75 73 75 61 6c 6c 79 20 68 61 73 20 61 20 64 | usually has a d| 000003f0 65 6c 61 79 20 74 69 6d 65 20 6f 66 20 33 30 20 |elay time of 30 | 00000400 73 65 63 6f 6e 64 73 29 2e 0a 42 79 20 64 65 66 |seconds)..By def| 00000410 61 75 6c 74 20 74 68 65 20 73 63 72 65 65 6e 73 |ault the screens| 00000420 61 76 65 72 20 72 75 6e 73 20 69 6e 20 74 68 65 |aver runs in the| 00000430 20 63 75 72 72 65 6e 74 20 64 65 73 6b 74 6f 70 | current desktop| 00000440 20 6d 6f 64 65 2e 20 4d 6f 76 65 20 74 68 65 20 | mode. Move the | 00000450 6d 6f 75 73 65 0a 6f 72 20 70 72 65 73 73 20 53 |mouse.or press S| 00000460 48 49 46 54 20 74 6f 20 72 65 74 75 72 6e 20 74 |HIFT to return t| 00000470 6f 20 74 68 65 20 64 65 73 6b 74 6f 70 2e 0a 0a |o the desktop...| 00000480 20 20 54 68 69 6e 67 73 20 63 61 6e 20 67 65 74 | Things can get| 00000490 20 52 45 41 4c 4c 59 20 66 75 6e 20 77 68 65 6e | REALLY fun when| 000004a0 20 79 6f 75 20 68 61 76 65 20 73 61 79 20 66 69 | you have say fi| 000004b0 76 65 20 63 6f 70 69 65 73 20 6f 66 20 74 68 65 |ve copies of the| 000004c0 20 73 63 72 65 65 6e 73 61 76 65 72 0a 6d 75 6c | screensaver.mul| 000004d0 74 69 74 61 73 6b 69 6e 67 20 74 6f 67 65 74 68 |titasking togeth| 000004e0 65 72 20 2d 20 74 68 65 79 20 77 69 6c 6c 20 61 |er - they will a| 000004f0 6c 6c 20 73 74 61 72 74 20 61 74 20 74 68 65 20 |ll start at the | 00000500 73 61 6d 65 20 74 69 6d 65 21 20 46 6f 72 20 62 |same time! For b| 00000510 65 73 74 0a 72 65 73 75 6c 74 73 20 64 6f 6e 60 |est.results don`| 00000520 74 20 75 73 65 20 72 65 66 6c 65 63 74 69 6f 6e |t use reflection| 00000530 20 77 68 65 6e 20 75 73 69 6e 67 20 6d 75 6c 74 | when using mult| 00000540 69 70 6c 65 20 63 6f 70 69 65 73 2e 0a 0a 4c 49 |iple copies...LI| 00000550 43 45 4e 43 45 0a 0a 20 20 54 68 69 73 20 70 72 |CENCE.. This pr| 00000560 6f 67 72 61 6d 20 69 73 20 46 52 45 45 57 41 52 |ogram is FREEWAR| 00000570 45 20 73 6f 20 6d 61 79 20 62 65 20 75 73 65 64 |E so may be used| 00000580 20 61 6e 64 20 64 69 73 74 72 69 62 75 74 65 64 | and distributed| 00000590 20 66 72 65 65 6c 79 20 77 69 74 68 6f 75 74 0a | freely without.| 000005a0 6d 6f 6e 65 79 20 63 68 61 6e 67 69 6e 67 20 68 |money changing h| 000005b0 61 6e 64 73 20 28 6f 74 68 65 72 20 74 68 61 6e |ands (other than| 000005c0 20 64 69 73 63 20 70 72 69 63 65 73 20 66 6f 72 | disc prices for| 000005d0 20 50 44 20 6c 69 62 72 61 72 69 65 73 20 65 74 | PD libraries et| 000005e0 63 2e 29 20 61 73 20 6c 6f 6e 67 0a 61 73 20 69 |c.) as long.as i| 000005f0 74 20 72 65 6d 61 69 6e 73 20 63 6f 6d 70 6c 65 |t remains comple| 00000600 74 65 20 61 6e 64 20 75 6e 61 6c 74 65 72 65 64 |te and unaltered| 00000610 2e 20 0a 0a 44 45 54 41 49 4c 45 44 20 49 4e 53 |. ..DETAILED INS| 00000620 54 52 55 43 54 49 4f 4e 53 0a 0a 20 20 44 6f 75 |TRUCTIONS.. Dou| 00000630 62 6c 65 2d 63 6c 69 63 6b 20 6f 6e 20 74 68 65 |ble-click on the| 00000640 20 69 63 6f 6e 20 69 6e 20 74 68 65 20 66 69 6c | icon in the fil| 00000650 65 72 20 77 69 6e 64 6f 77 20 28 77 68 79 20 49 |er window (why I| 00000660 20 61 6d 20 62 6f 74 68 65 72 69 6e 67 20 74 6f | am bothering to| 00000670 20 73 61 79 0a 74 68 69 73 20 49 20 68 61 76 65 | say.this I have| 00000680 20 6e 6f 20 69 64 65 61 2e 2e 2e 29 20 61 6e 64 | no idea...) and| 00000690 20 74 68 65 20 70 72 6f 67 72 61 6d 20 77 69 6c | the program wil| 000006a0 6c 20 69 6e 73 74 61 6c 6c 20 69 74 73 65 6c 66 |l install itself| 000006b0 20 6f 6e 20 74 68 65 20 69 63 6f 6e 20 62 61 72 | on the icon bar| 000006c0 2e 0a 0a 20 20 43 6c 69 63 6b 69 6e 67 20 4d 45 |... Clicking ME| 000006d0 4e 55 20 6f 6e 20 74 68 65 20 69 63 6f 6e 20 62 |NU on the icon b| 000006e0 61 72 20 69 63 6f 6e 20 62 72 69 6e 67 73 20 75 |ar icon brings u| 000006f0 70 20 61 20 6d 65 6e 75 20 77 69 74 68 20 74 68 |p a menu with th| 00000700 72 65 65 20 65 6e 74 72 69 65 73 3a 0a 49 6e 66 |ree entries:.Inf| 00000710 6f 2c 20 48 65 6c 70 20 8c 2c 20 51 75 69 74 2e |o, Help ., Quit.| 00000720 20 49 6e 66 6f 20 6c 65 61 64 73 20 74 6f 20 61 | Info leads to a| 00000730 6e 20 69 6e 66 6f 72 6d 61 74 69 6f 6e 20 62 6f |n information bo| 00000740 78 20 74 68 69 6e 67 79 20 28 79 65 73 20 49 20 |x thingy (yes I | 00000750 6b 6e 6f 77 0a 60 54 6f 74 61 6c 6c 79 20 61 6d |know.`Totally am| 00000760 61 7a 69 6e 67 20 73 63 72 65 65 6e 73 61 76 65 |azing screensave| 00000770 72 60 20 73 6f 75 6e 64 73 20 72 65 61 6c 6c 79 |r` sounds really| 00000780 20 70 72 65 74 65 6e 74 69 6f 75 73 20 62 75 74 | pretentious but| 00000790 20 6e 6f 20 6f 6e 65 20 74 61 6b 65 73 0a 74 68 | no one takes.th| 000007a0 65 73 65 20 70 75 72 70 6f 73 65 20 66 69 65 6c |ese purpose fiel| 000007b0 64 73 20 73 65 72 69 6f 75 73 6c 79 20 61 6e 79 |ds seriously any| 000007c0 77 61 79 29 2e 20 48 65 6c 70 a0 8c 20 28 6e 6f |way). Help.. (no| 000007d0 74 65 20 75 73 65 20 6f 66 20 72 65 61 6c 6c 79 |te use of really| 000007e0 20 63 6f 6f 6c 0a 65 6c 6c 69 70 73 69 73 29 20 | cool.ellipsis) | 000007f0 6c 6f 61 64 73 20 74 68 69 73 20 70 61 72 74 69 |loads this parti| 00000800 63 75 6c 61 72 20 66 69 6c 65 20 69 6e 74 6f 20 |cular file into | 00000810 74 68 65 20 6e 65 61 72 65 73 74 20 66 72 69 65 |the nearest frie| 00000820 6e 64 6c 79 20 74 65 78 74 20 65 64 69 74 6f 72 |ndly text editor| 00000830 2e 0a 51 75 69 74 20 74 65 72 6d 69 6e 61 74 65 |..Quit terminate| 00000840 73 20 65 78 65 63 75 74 69 6f 6e 20 6f 66 20 74 |s execution of t| 00000850 68 65 20 70 72 6f 67 67 79 20 28 6e 6f 74 20 74 |he proggy (not t| 00000860 68 61 74 20 79 6f 75 60 64 20 77 61 6e 74 20 74 |hat you`d want t| 00000870 6f 20 64 6f 20 74 68 61 74 29 2e 0a 0a 20 20 53 |o do that)... S| 00000880 45 4c 45 43 54 20 6f 70 65 6e 73 20 74 68 65 20 |ELECT opens the | 00000890 63 6f 6e 66 69 67 75 72 61 74 69 6f 6e 20 77 69 |configuration wi| 000008a0 6e 64 6f 77 20 61 73 20 6d 65 6e 74 69 6f 6e 65 |ndow as mentione| 000008b0 64 20 62 65 66 6f 72 65 2e 20 54 68 65 20 66 69 |d before. The fi| 000008c0 65 6c 64 73 20 61 72 65 0a 64 65 73 63 72 69 62 |elds are.describ| 000008d0 65 64 20 62 65 6c 6f 77 2e 20 54 69 6d 65 20 44 |ed below. Time D| 000008e0 65 6c 61 79 20 73 65 74 73 20 68 6f 77 20 6c 6f |elay sets how lo| 000008f0 6e 67 20 61 20 70 65 72 69 6f 64 20 6f 66 20 64 |ng a period of d| 00000900 65 73 6b 74 6f 70 20 69 6e 61 63 74 69 76 69 74 |esktop inactivit| 00000910 79 20 69 73 0a 72 65 71 75 69 72 65 64 20 74 6f |y is.required to| 00000920 20 74 72 69 67 67 65 72 20 74 68 65 20 73 63 72 | trigger the scr| 00000930 65 65 6e 73 61 76 65 72 2e 20 54 68 65 72 65 20 |eensaver. There | 00000940 69 73 20 74 68 65 20 6f 70 74 69 6f 6e 20 74 6f |is the option to| 00000950 20 73 65 74 20 77 68 65 74 68 65 72 20 6f 72 0a | set whether or.| 00000960 6e 6f 74 20 74 68 65 20 73 63 72 65 65 6e 73 61 |not the screensa| 00000970 76 65 72 20 6d 75 6c 74 69 74 61 73 6b 73 20 62 |ver multitasks b| 00000980 65 74 77 65 65 6e 20 64 72 61 77 69 6e 67 20 65 |etween drawing e| 00000990 61 63 68 20 6c 69 6e 65 2e 20 4e 6f 74 65 20 74 |ach line. Note t| 000009a0 68 61 74 0a 6d 75 6c 74 69 74 61 73 6b 69 6e 67 |hat.multitasking| 000009b0 20 63 61 6e 20 73 6c 6f 77 20 69 74 20 64 6f 77 | can slow it dow| 000009c0 6e 20 61 20 4c 4f 54 20 65 73 70 65 63 69 61 6c |n a LOT especial| 000009d0 6c 79 20 69 66 20 66 69 6c 65 20 6f 70 65 72 61 |ly if file opera| 000009e0 74 69 6f 6e 73 20 61 72 65 20 67 6f 69 6e 67 0a |tions are going.| 000009f0 6f 6e 20 77 68 69 6c 65 20 69 74 60 73 20 74 72 |on while it`s tr| 00000a00 79 69 6e 67 20 74 6f 20 64 72 61 77 20 6c 69 6e |ying to draw lin| 00000a10 65 73 20 61 6c 6c 20 6f 76 65 72 20 74 68 65 20 |es all over the | 00000a20 73 63 72 65 65 6e 2e 20 49 66 20 6d 75 6c 74 69 |screen. If multi| 00000a30 70 6c 65 20 63 6f 70 69 65 73 0a 61 72 65 20 6c |ple copies.are l| 00000a40 6f 61 64 65 64 20 74 68 65 6e 20 6f 6e 6c 79 20 |oaded then only | 00000a50 6f 6e 65 73 20 77 69 74 68 20 74 68 65 20 6d 75 |ones with the mu| 00000a60 6c 74 69 74 61 73 6b 69 6e 67 20 6f 70 74 69 6f |ltitasking optio| 00000a70 6e 20 73 65 74 20 77 69 6c 6c 20 73 74 61 72 74 |n set will start| 00000a80 20 75 70 2e 0a 0a 20 20 53 63 72 65 65 6e 20 6d | up... Screen m| 00000a90 6f 64 65 20 61 6c 6c 6f 77 73 20 79 6f 75 20 74 |ode allows you t| 00000aa0 6f 20 73 70 65 63 69 66 79 20 74 68 65 20 72 65 |o specify the re| 00000ab0 73 6f 6c 75 74 69 6f 6e 2f 63 6f 6c 6f 75 72 20 |solution/colour | 00000ac0 64 65 70 74 68 20 74 68 65 0a 73 63 72 65 65 6e |depth the.screen| 00000ad0 73 61 76 65 72 20 6f 70 65 72 61 74 65 73 20 69 |saver operates i| 00000ae0 6e 2e 20 44 65 73 6b 74 6f 70 20 6d 6f 64 65 20 |n. Desktop mode | 00000af0 75 73 65 73 20 74 68 65 20 63 75 72 72 65 6e 74 |uses the current| 00000b00 20 64 65 73 6b 74 6f 70 20 6d 6f 64 65 2e 20 4d | desktop mode. M| 00000b10 6f 64 65 0a 6e 75 6d 62 65 72 20 61 6c 6c 6f 77 |ode.number allow| 00000b20 73 20 52 49 53 43 20 4f 53 20 33 2e 31 20 75 73 |s RISC OS 3.1 us| 00000b30 65 72 73 20 74 6f 20 73 70 65 63 69 66 79 20 61 |ers to specify a| 00000b40 20 6d 6f 64 65 20 6e 75 6d 62 65 72 3b 20 61 20 | mode number; a | 00000b50 32 35 36 20 63 6f 6c 6f 75 72 20 6f 6e 65 0a 69 |256 colour one.i| 00000b60 73 20 70 72 65 66 65 72 61 62 6c 65 20 6c 69 6b |s preferable lik| 00000b70 65 20 6d 6f 64 65 20 31 35 20 28 43 47 41 29 20 |e mode 15 (CGA) | 00000b80 6f 72 20 6d 6f 64 65 20 32 38 20 28 56 47 41 29 |or mode 28 (VGA)| 00000b90 2e 20 4d 6f 64 65 20 73 74 72 69 6e 67 20 61 6c |. 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The.centre of| 00001b10 20 74 68 65 20 73 63 72 65 65 6e 20 69 73 20 73 | the screen is s| 00001b20 65 74 20 74 6f 20 62 65 20 74 68 65 20 6f 72 69 |et to be the ori| 00001b30 67 69 6e 20 73 6f 20 72 65 66 6c 65 63 74 69 6f |gin so reflectio| 00001b40 6e 20 69 73 20 73 69 6d 70 6c 79 20 64 6f 6e 65 |n is simply done| 00001b50 20 62 79 0a 63 68 61 6e 67 69 6e 67 20 74 68 65 | by.changing the| 00001b60 20 73 69 67 6e 20 6f 66 20 74 68 65 20 78 2c 20 | sign of the x, | 00001b70 79 20 6f 72 20 62 6f 74 68 20 63 6f 2d 6f 72 64 |y or both co-ord| 00001b80 69 6e 61 74 65 73 20 61 6e 64 20 64 72 61 77 69 |inates and drawi| 00001b90 6e 67 20 74 68 65 0a 6c 69 6e 65 2f 63 75 72 76 |ng the.line/curv| 00001ba0 65 20 61 67 61 69 6e 2e 20 54 68 65 20 63 6f 6c |e again. The col| 00001bb0 6f 75 72 20 69 73 20 73 65 74 20 75 73 69 6e 67 |our is set using| 00001bc0 20 74 68 65 20 43 6f 6c 6f 75 72 54 72 61 6e 73 | the ColourTrans| 00001bd0 20 6d 6f 64 75 6c 65 20 74 6f 20 70 69 63 6b 20 | module to pick | 00001be0 74 68 65 0a 63 6c 6f 73 65 73 74 20 6d 61 74 63 |the.closest matc| 00001bf0 68 20 61 6e 64 20 64 69 74 68 65 72 69 6e 67 20 |h and dithering | 00001c00 69 73 20 75 73 65 64 2e 0a 0a 53 50 45 45 44 20 |is used...SPEED | 00001c10 49 4d 50 52 4f 56 45 4d 45 4e 54 53 20 28 41 52 |IMPROVEMENTS (AR| 00001c20 4d 32 2f 32 35 30 29 0a 0a 20 20 54 68 65 20 63 |M2/250).. The c| 00001c30 61 6c 6c 73 20 74 6f 20 74 68 65 20 6f 70 65 72 |alls to the oper| 00001c40 61 74 69 6e 67 20 73 79 73 74 65 6d 20 74 6f 20 |ating system to | 00001c50 64 72 61 77 20 74 68 65 20 6c 69 6e 65 73 20 63 |draw the lines c| 00001c60 61 6e 20 62 65 20 6d 61 64 65 20 4d 55 43 48 0a |an be made MUCH.| 00001c70 66 61 73 74 65 72 20 6f 6e 20 52 49 53 43 20 4f |faster on RISC O| 00001c80 53 20 33 2e 31 20 62 79 20 73 70 65 65 64 69 6e |S 3.1 by speedin| 00001c90 67 20 75 70 20 74 68 65 20 52 4f 4d 60 73 2e 20 |g up the ROM`s. | 00001ca0 54 6f 20 64 6f 20 74 68 69 73 20 79 6f 75 20 6e |To do this you n| 00001cb0 65 65 64 20 74 6f 20 74 79 70 65 0a 53 59 53 a0 |eed to type.SYS.| 00001cc0 22 4f 53 5f 55 70 64 61 74 65 4d 45 4d 43 22 2c |"OS_UpdateMEMC",| 00001cd0 31 36 30 2c 32 34 30 20 61 74 20 74 68 65 20 42 |160,240 at the B| 00001ce0 41 53 49 43 20 70 72 6f 6d 70 74 20 28 6f 72 20 |ASIC prompt (or | 00001cf0 63 72 65 61 74 65 20 61 20 42 41 53 49 43 20 70 |create a BASIC p| 00001d00 72 6f 67 72 61 6d 0a 61 6e 64 20 72 75 6e 20 69 |rogram.and run i| 00001d10 74 29 2e 20 2a 52 4d 46 61 73 74 65 72 20 43 6f |t). *RMFaster Co| 00001d20 6c 6f 75 72 54 72 61 6e 73 20 6d 61 79 20 68 61 |lourTrans may ha| 00001d30 76 65 20 73 6f 6d 65 20 65 66 66 65 63 74 2e 20 |ve some effect. | 00001d40 41 6c 74 65 72 6e 61 74 69 76 65 6c 79 2c 20 74 |Alternatively, t| 00001d50 6f 0a 69 6e 63 72 65 61 73 65 20 73 70 65 65 64 |o.increase speed| 00001d60 20 74 72 79 20 75 73 69 6e 67 20 6c 65 73 73 20 | try using less | 00001d70 72 65 66 6c 65 63 74 69 6f 6e 20 61 6e 64 20 6c |reflection and l| 00001d80 6f 77 65 72 20 62 65 7a 69 65 72 20 6c 69 6e 65 |ower bezier line| 00001d90 20 71 75 61 6c 69 74 79 20 61 6e 64 0a 6e 6f 74 | quality and.not| 00001da0 20 74 72 79 69 6e 67 20 74 6f 20 6d 75 6c 74 69 | trying to multi| 00001db0 74 61 73 6b 20 39 39 20 63 6f 70 69 65 73 20 74 |task 99 copies t| 00001dc0 6f 67 65 74 68 65 72 20 2d 20 6f 72 20 62 75 79 |ogether - or buy| 00001dd0 20 61 20 52 69 73 63 50 43 21 0a 0a 54 48 45 20 | a RiscPC!..THE | 00001de0 41 55 54 48 4f 52 0a 0a 20 20 41 20 68 75 6d 62 |AUTHOR.. A humb| 00001df0 6c 65 20 70 65 6e 6e 69 6c 65 73 73 20 70 68 79 |le penniless phy| 00001e00 73 69 63 73 20 73 74 75 64 65 6e 74 20 73 6c 61 |sics student sla| 00001e10 76 69 6e 67 20 61 77 61 79 20 6f 76 65 72 20 68 |ving away over h| 00001e20 69 73 20 41 72 63 20 66 6f 72 20 68 6f 75 72 73 |is Arc for hours| 00001e30 20 6f 6e 0a 65 6e 64 20 77 68 65 6e 20 74 68 65 | on.end when the| 00001e40 72 65 20 61 72 65 20 66 61 72 20 6d 6f 72 65 20 |re are far more | 00001e50 65 78 63 69 74 69 6e 67 20 74 68 69 6e 67 73 20 |exciting things | 00001e60 6f 6e 20 6f 66 66 65 72 20 2e 2e 2e 2e 20 0a 0a |on offer .... ..| 00001e70 52 69 63 68 61 72 64 20 53 70 65 6e 63 65 72 20 |Richard Spencer | 00001e80 20 20 20 20 20 20 20 20 20 20 20 70 68 79 73 72 | physr| 00001e90 73 40 6c 65 65 64 73 2e 61 63 2e 75 6b 20 28 75 |s@leeds.ac.uk (u| 00001ea0 6e 74 69 6c 20 4d 61 79 20 32 30 30 31 29 0a 0a |ntil May 2001)..| 00001eb0 4d 6f 72 74 61 69 6e 20 48 6f 75 73 65 0a 42 6f |Mortain House.Bo| 00001ec0 64 69 6e 67 74 6f 6e 20 48 61 6c 6c 0a 4f 74 6c |dington Hall.Otl| 00001ed0 65 79 20 52 6f 61 64 0a 4c 45 45 44 53 0a 4c 53 |ey Road.LEEDS.LS| 00001ee0 31 36 20 35 50 54 0a 0a 28 75 6e 74 69 6c 20 4a |16 5PT..(until J| 00001ef0 75 6e 65 20 31 39 39 38 29 0a 0a 59 6f 75 20 6b |une 1998)..You k| 00001f00 6e 6f 77 20 77 68 61 74 20 74 6f 20 64 6f 21 0a |now what to do!.| 00001f10
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