Home » Archimedes archive » Acorn User » AU 1994-05.adf » !StarInfo_StarInfo » Vlietinck/Text
Vlietinck/Text
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 1994-05.adf » !StarInfo_StarInfo |
| Filename: | Vlietinck/Text |
| Read OK: | ✔ |
| File size: | 148A bytes |
| Load address: | 0000 |
| Exec address: | 0000 |
File contents
24-10-1993.
Hello Dave & Dave
It has been some time ago since my last submission. So here
are some of the latest programs I have been written.
All are of course graphics programs, in a mix of basic and assembler.
- FFTscreen calculates the two dimensional FFT of some screens.
- Julian is a julia animator.
- Trackman is a mandelbort-julia (please keep on reading) generator.
The facts that distinguish this program from the rest are speed,
originality and flexibility.
- Stringz is an updated version of my 1D-wave program.
Further explanation follows.
Now about some financial matters. After exchanging a cheque form you
for my currency and because the cheque is foreign, about only half
of the money is what is left for me.
So instead of money I very much would like to get a free subscription
to your magazine and monthly disc. I hope you will agree with this.
Bye and maybe see you at the show.
Jan vlietinck
Essendreef 15
8300 Knokke-Heist
Belgium
FFTscreen
=========
The FFT(fast fourier transform) of a 256x256 matrix is calculated.
This is achieved by first calculating the 256-point FFT of each row
and then by calculating the FFT of each column.
The root of the sum of the squares of the real and imaginary part is
then shown in colour. It takes about five seconds to perform this
'complex' calculation. Ten successive screens can be processed by
pressing a key. You may wish to transform a screen of your own.
This can easily be done by adding other code to the CASE structure.
When decreasing the variable PW on the fourth line with one,
the matrix is reduced with a factor of 2 in both directions.
Julian
======
This is a realtime, interactive, accurate julia fractal animation.
Two operation modes are available, depending on the desktop mode
you are in when starting the program. In a high resolution mode,
mode 19 is selected, else mode 1 is used.
Moving the mouse causes the julia fractal gradually to change.
Dragging the mouse causes finer changes.
The underlying mandelbrot picture shows the corresponding point,
pointed to by the pointer that is used to generate the julia fractal.
Also the coordinates of this point are shown.
The fractals are calculated according a recursive version of the
inverse iteration method.
Trackman
========
This program employs a novel technique to speed up the generation of
fractals. The program tries to track only the path between two domains
of colour. When the border of these domains is calculated the rest
of the points are easily filled in. This scheme leads to significant
time reduction since much fewer pixels need to be calculated. Especially
in high resolution modes the speedup can be great.
The program supports the 256 colour modes 13,21 and 28 also the 16 colour
modes 9,20,27 and 31 are supported.
The control of the program is by means of the keyboard and the mouse.
To perform a fractal generation each time a key has to be pressed.
M : generates a mandelbrot fractal
J : generates a julia fractal
R : redraws the initial fractal
S : prompts for a name of the screen to be saved
C & D : used to cycle the colour palette.
V : to switch on and off the video DMA, turning off means shorter
generation time since no DMA overhead occurs.
N : used to switch to another screen mode
H : shows help
The mouse buttons do the following
left : zoom out
right : zoom in
middle : start generation
When you are asked to enter the number of iterations pressing RETURN
causes 100 iterations to be selected.
You can interrupt the generation by pressing ESCAPE.
The initial help can be removed by pressing SPACE.
Another feature is incorporated to generate the sprites that are used
in the program Julian (This was meant to be used by former yellow pages
typers). Pressing SHIFT Q in the modes 13 and 21 causes these fractals
to be saved.
When switching to julia-generation the current mandelbrot screen is saved.
When switching back with 'M' it is reloaded.
So ensure that a disc is inserted when you only have a floppy-drive.
Saving the screen to floppy may actually be slower than redrawing.
So you better set the filling systen to RAM with *RAM and make it big
enough. Or you can set the variable 'save' on the third line to false.
The program uses a fairly big chunk of memory on top op the system stack.
This amount of memory increases with the complexity of the fractal.
It is therefore advisable to allocate at least 300kb before starting the
program.
Stringz
=======
This is an improved version of my former STRING program.
Enhancements are: Better mouse control, nicer colour and most important
no more vertical gaps between pixels.
Clicking select wipes the screen and restarts, clicking adjust ends
the program
With the variables 'prop' and 'damp' in the range 0-31 you can set
the propagation speed and damping of the wave.
Arm3 users may wish to use this program in mode 21 instead of mode 13.
To achieve this you can set the variable 'high' on the third line to TRUE.
00000000 20 20 20 20 20 20 20 20 20 20 20 20 20 20 20 20 | | * 00000030 20 20 20 20 20 20 20 20 20 20 20 20 20 32 34 2d | 24-| 00000040 31 30 2d 31 39 39 33 2e 0a 0a 48 65 6c 6c 6f 20 |10-1993...Hello | 00000050 44 61 76 65 20 26 20 44 61 76 65 0a 0a 0a 49 74 |Dave & Dave...It| 00000060 20 68 61 73 20 62 65 65 6e 20 73 6f 6d 65 20 74 | has been some t| 00000070 69 6d 65 20 61 67 6f 20 73 69 6e 63 65 20 6d 79 |ime ago since my| 00000080 20 6c 61 73 74 20 73 75 62 6d 69 73 73 69 6f 6e | last submission| 00000090 2e 20 53 6f 20 68 65 72 65 0a 61 72 65 20 73 6f |. So here.are so| 000000a0 6d 65 20 6f 66 20 74 68 65 20 6c 61 74 65 73 74 |me of the latest| 000000b0 20 70 72 6f 67 72 61 6d 73 20 49 20 68 61 76 65 | programs I have| 000000c0 20 62 65 65 6e 20 77 72 69 74 74 65 6e 2e 0a 41 | been written..A| 000000d0 6c 6c 20 61 72 65 20 6f 66 20 63 6f 75 72 73 65 |ll are of course| 000000e0 20 67 72 61 70 68 69 63 73 20 70 72 6f 67 72 61 | graphics progra| 000000f0 6d 73 2c 20 69 6e 20 61 20 6d 69 78 20 6f 66 20 |ms, in a mix of | 00000100 62 61 73 69 63 20 61 6e 64 20 61 73 73 65 6d 62 |basic and assemb| 00000110 6c 65 72 2e 0a 0a 20 2d 20 46 46 54 73 63 72 65 |ler... - FFTscre| 00000120 65 6e 20 63 61 6c 63 75 6c 61 74 65 73 20 74 68 |en calculates th| 00000130 65 20 74 77 6f 20 64 69 6d 65 6e 73 69 6f 6e 61 |e two dimensiona| 00000140 6c 20 46 46 54 20 6f 66 20 73 6f 6d 65 20 73 63 |l FFT of some sc| 00000150 72 65 65 6e 73 2e 0a 20 2d 20 4a 75 6c 69 61 6e |reens.. - Julian| 00000160 20 69 73 20 61 20 6a 75 6c 69 61 20 61 6e 69 6d | is a julia anim| 00000170 61 74 6f 72 2e 0a 20 2d 20 54 72 61 63 6b 6d 61 |ator.. - Trackma| 00000180 6e 20 69 73 20 61 20 6d 61 6e 64 65 6c 62 6f 72 |n is a mandelbor| 00000190 74 2d 6a 75 6c 69 61 20 28 70 6c 65 61 73 65 20 |t-julia (please | 000001a0 6b 65 65 70 20 6f 6e 20 72 65 61 64 69 6e 67 29 |keep on reading)| 000001b0 20 67 65 6e 65 72 61 74 6f 72 2e 0a 20 20 20 54 | generator.. T| 000001c0 68 65 20 66 61 63 74 73 20 74 68 61 74 20 64 69 |he facts that di| 000001d0 73 74 69 6e 67 75 69 73 68 20 74 68 69 73 20 70 |stinguish this p| 000001e0 72 6f 67 72 61 6d 20 66 72 6f 6d 20 74 68 65 20 |rogram from the | 000001f0 72 65 73 74 20 61 72 65 20 73 70 65 65 64 2c 20 |rest are speed, | 00000200 0a 20 20 20 6f 72 69 67 69 6e 61 6c 69 74 79 20 |. originality | 00000210 61 6e 64 20 66 6c 65 78 69 62 69 6c 69 74 79 2e |and flexibility.| 00000220 0a 20 2d 20 53 74 72 69 6e 67 7a 20 69 73 20 61 |. - Stringz is a| 00000230 6e 20 75 70 64 61 74 65 64 20 76 65 72 73 69 6f |n updated versio| 00000240 6e 20 6f 66 20 6d 79 20 31 44 2d 77 61 76 65 20 |n of my 1D-wave | 00000250 70 72 6f 67 72 61 6d 2e 0a 20 20 20 20 20 20 20 |program.. | 00000260 20 20 20 20 20 20 20 0a 46 75 72 74 68 65 72 20 | .Further | 00000270 65 78 70 6c 61 6e 61 74 69 6f 6e 20 66 6f 6c 6c |explanation foll| 00000280 6f 77 73 2e 0a 0a 4e 6f 77 20 61 62 6f 75 74 20 |ows...Now about | 00000290 73 6f 6d 65 20 66 69 6e 61 6e 63 69 61 6c 20 6d |some financial m| 000002a0 61 74 74 65 72 73 2e 20 41 66 74 65 72 20 65 78 |atters. After ex| 000002b0 63 68 61 6e 67 69 6e 67 20 61 20 63 68 65 71 75 |changing a chequ| 000002c0 65 20 66 6f 72 6d 20 79 6f 75 0a 66 6f 72 20 6d |e form you.for m| 000002d0 79 20 63 75 72 72 65 6e 63 79 20 61 6e 64 20 62 |y currency and b| 000002e0 65 63 61 75 73 65 20 74 68 65 20 63 68 65 71 75 |ecause the chequ| 000002f0 65 20 69 73 20 66 6f 72 65 69 67 6e 2c 20 61 62 |e is foreign, ab| 00000300 6f 75 74 20 6f 6e 6c 79 20 68 61 6c 66 0a 6f 66 |out only half.of| 00000310 20 74 68 65 20 6d 6f 6e 65 79 20 69 73 20 77 68 | the money is wh| 00000320 61 74 20 69 73 20 6c 65 66 74 20 66 6f 72 20 6d |at is left for m| 00000330 65 2e 0a 53 6f 20 69 6e 73 74 65 61 64 20 6f 66 |e..So instead of| 00000340 20 6d 6f 6e 65 79 20 49 20 76 65 72 79 20 6d 75 | money I very mu| 00000350 63 68 20 77 6f 75 6c 64 20 6c 69 6b 65 20 74 6f |ch would like to| 00000360 20 67 65 74 20 61 20 66 72 65 65 20 73 75 62 73 | get a free subs| 00000370 63 72 69 70 74 69 6f 6e 0a 74 6f 20 79 6f 75 72 |cription.to your| 00000380 20 6d 61 67 61 7a 69 6e 65 20 61 6e 64 20 6d 6f | magazine and mo| 00000390 6e 74 68 6c 79 20 64 69 73 63 2e 20 49 20 68 6f |nthly disc. I ho| 000003a0 70 65 20 79 6f 75 20 77 69 6c 6c 20 61 67 72 65 |pe you will agre| 000003b0 65 20 77 69 74 68 20 74 68 69 73 2e 0a 20 20 20 |e with this.. | 000003c0 20 20 20 20 20 20 20 20 20 20 20 20 20 20 20 20 | | * 000003f0 20 0a 0a 42 79 65 20 61 6e 64 20 6d 61 79 62 65 | ..Bye and maybe| 00000400 20 73 65 65 20 79 6f 75 20 61 74 20 74 68 65 20 | see you at the | 00000410 73 68 6f 77 2e 0a 0a 4a 61 6e 20 76 6c 69 65 74 |show...Jan vliet| 00000420 69 6e 63 6b 20 0a 45 73 73 65 6e 64 72 65 65 66 |inck .Essendreef| 00000430 20 31 35 0a 38 33 30 30 20 4b 6e 6f 6b 6b 65 2d | 15.8300 Knokke-| 00000440 48 65 69 73 74 0a 42 65 6c 67 69 75 6d 0a 0a 0a |Heist.Belgium...| 00000450 0a 46 46 54 73 63 72 65 65 6e 0a 3d 3d 3d 3d 3d |.FFTscreen.=====| 00000460 3d 3d 3d 3d 0a 0a 54 68 65 20 46 46 54 28 66 61 |====..The FFT(fa| 00000470 73 74 20 66 6f 75 72 69 65 72 20 74 72 61 6e 73 |st fourier trans| 00000480 66 6f 72 6d 29 20 6f 66 20 61 20 32 35 36 78 32 |form) of a 256x2| 00000490 35 36 20 6d 61 74 72 69 78 20 69 73 20 63 61 6c |56 matrix is cal| 000004a0 63 75 6c 61 74 65 64 2e 0a 54 68 69 73 20 69 73 |culated..This is| 000004b0 20 61 63 68 69 65 76 65 64 20 62 79 20 66 69 72 | achieved by fir| 000004c0 73 74 20 63 61 6c 63 75 6c 61 74 69 6e 67 20 74 |st calculating t| 000004d0 68 65 20 32 35 36 2d 70 6f 69 6e 74 20 46 46 54 |he 256-point FFT| 000004e0 20 6f 66 20 65 61 63 68 20 72 6f 77 0a 61 6e 64 | of each row.and| 000004f0 20 74 68 65 6e 20 62 79 20 63 61 6c 63 75 6c 61 | then by calcula| 00000500 74 69 6e 67 20 74 68 65 20 46 46 54 20 6f 66 20 |ting the FFT of | 00000510 65 61 63 68 20 63 6f 6c 75 6d 6e 2e 0a 54 68 65 |each column..The| 00000520 20 72 6f 6f 74 20 6f 66 20 74 68 65 20 73 75 6d | root of the sum| 00000530 20 6f 66 20 74 68 65 20 73 71 75 61 72 65 73 20 | of the squares | 00000540 6f 66 20 74 68 65 20 72 65 61 6c 20 61 6e 64 20 |of the real and | 00000550 69 6d 61 67 69 6e 61 72 79 20 70 61 72 74 20 69 |imaginary part i| 00000560 73 0a 74 68 65 6e 20 73 68 6f 77 6e 20 69 6e 20 |s.then shown in | 00000570 63 6f 6c 6f 75 72 2e 20 49 74 20 74 61 6b 65 73 |colour. It takes| 00000580 20 61 62 6f 75 74 20 66 69 76 65 20 73 65 63 6f | about five seco| 00000590 6e 64 73 20 74 6f 20 70 65 72 66 6f 72 6d 20 74 |nds to perform t| 000005a0 68 69 73 0a 27 63 6f 6d 70 6c 65 78 27 20 63 61 |his.'complex' ca| 000005b0 6c 63 75 6c 61 74 69 6f 6e 2e 20 54 65 6e 20 73 |lculation. Ten s| 000005c0 75 63 63 65 73 73 69 76 65 20 73 63 72 65 65 6e |uccessive screen| 000005d0 73 20 63 61 6e 20 62 65 20 70 72 6f 63 65 73 73 |s can be process| 000005e0 65 64 20 62 79 0a 70 72 65 73 73 69 6e 67 20 61 |ed by.pressing a| 000005f0 20 6b 65 79 2e 20 59 6f 75 20 6d 61 79 20 77 69 | key. You may wi| 00000600 73 68 20 74 6f 20 74 72 61 6e 73 66 6f 72 6d 20 |sh to transform | 00000610 61 20 73 63 72 65 65 6e 20 6f 66 20 79 6f 75 72 |a screen of your| 00000620 20 6f 77 6e 2e 0a 54 68 69 73 20 63 61 6e 20 65 | own..This can e| 00000630 61 73 69 6c 79 20 62 65 20 64 6f 6e 65 20 62 79 |asily be done by| 00000640 20 61 64 64 69 6e 67 20 6f 74 68 65 72 20 63 6f | adding other co| 00000650 64 65 20 74 6f 20 74 68 65 20 43 41 53 45 20 73 |de to the CASE s| 00000660 74 72 75 63 74 75 72 65 2e 0a 57 68 65 6e 20 64 |tructure..When d| 00000670 65 63 72 65 61 73 69 6e 67 20 74 68 65 20 76 61 |ecreasing the va| 00000680 72 69 61 62 6c 65 20 50 57 20 6f 6e 20 74 68 65 |riable PW on the| 00000690 20 66 6f 75 72 74 68 20 6c 69 6e 65 20 77 69 74 | fourth line wit| 000006a0 68 20 6f 6e 65 2c 0a 74 68 65 20 6d 61 74 72 69 |h one,.the matri| 000006b0 78 20 69 73 20 72 65 64 75 63 65 64 20 77 69 74 |x is reduced wit| 000006c0 68 20 61 20 66 61 63 74 6f 72 20 6f 66 20 32 20 |h a factor of 2 | 000006d0 69 6e 20 62 6f 74 68 20 64 69 72 65 63 74 69 6f |in both directio| 000006e0 6e 73 2e 0a 0a 4a 75 6c 69 61 6e 0a 3d 3d 3d 3d |ns...Julian.====| 000006f0 3d 3d 0a 0a 54 68 69 73 20 69 73 20 61 20 72 65 |==..This is a re| 00000700 61 6c 74 69 6d 65 2c 20 69 6e 74 65 72 61 63 74 |altime, interact| 00000710 69 76 65 2c 20 61 63 63 75 72 61 74 65 20 6a 75 |ive, accurate ju| 00000720 6c 69 61 20 66 72 61 63 74 61 6c 20 61 6e 69 6d |lia fractal anim| 00000730 61 74 69 6f 6e 2e 0a 54 77 6f 20 6f 70 65 72 61 |ation..Two opera| 00000740 74 69 6f 6e 20 6d 6f 64 65 73 20 61 72 65 20 61 |tion modes are a| 00000750 76 61 69 6c 61 62 6c 65 2c 20 64 65 70 65 6e 64 |vailable, depend| 00000760 69 6e 67 20 6f 6e 20 74 68 65 20 64 65 73 6b 74 |ing on the deskt| 00000770 6f 70 20 6d 6f 64 65 0a 79 6f 75 20 61 72 65 20 |op mode.you are | 00000780 69 6e 20 77 68 65 6e 20 73 74 61 72 74 69 6e 67 |in when starting| 00000790 20 74 68 65 20 70 72 6f 67 72 61 6d 2e 20 49 6e | the program. In| 000007a0 20 61 20 68 69 67 68 20 72 65 73 6f 6c 75 74 69 | a high resoluti| 000007b0 6f 6e 20 6d 6f 64 65 2c 0a 6d 6f 64 65 20 31 39 |on mode,.mode 19| 000007c0 20 69 73 20 73 65 6c 65 63 74 65 64 2c 20 65 6c | is selected, el| 000007d0 73 65 20 6d 6f 64 65 20 31 20 69 73 20 75 73 65 |se mode 1 is use| 000007e0 64 2e 0a 4d 6f 76 69 6e 67 20 74 68 65 20 6d 6f |d..Moving the mo| 000007f0 75 73 65 20 63 61 75 73 65 73 20 74 68 65 20 6a |use causes the j| 00000800 75 6c 69 61 20 66 72 61 63 74 61 6c 20 67 72 61 |ulia fractal gra| 00000810 64 75 61 6c 6c 79 20 74 6f 20 63 68 61 6e 67 65 |dually to change| 00000820 2e 20 20 20 0a 44 72 61 67 67 69 6e 67 20 74 68 |. .Dragging th| 00000830 65 20 6d 6f 75 73 65 20 63 61 75 73 65 73 20 66 |e mouse causes f| 00000840 69 6e 65 72 20 63 68 61 6e 67 65 73 2e 0a 54 68 |iner changes..Th| 00000850 65 20 75 6e 64 65 72 6c 79 69 6e 67 20 6d 61 6e |e underlying man| 00000860 64 65 6c 62 72 6f 74 20 70 69 63 74 75 72 65 20 |delbrot picture | 00000870 73 68 6f 77 73 20 74 68 65 20 63 6f 72 72 65 73 |shows the corres| 00000880 70 6f 6e 64 69 6e 67 20 70 6f 69 6e 74 2c 0a 70 |ponding point,.p| 00000890 6f 69 6e 74 65 64 20 74 6f 20 62 79 20 74 68 65 |ointed to by the| 000008a0 20 70 6f 69 6e 74 65 72 20 74 68 61 74 20 69 73 | pointer that is| 000008b0 20 75 73 65 64 20 74 6f 20 67 65 6e 65 72 61 74 | used to generat| 000008c0 65 20 74 68 65 20 6a 75 6c 69 61 20 66 72 61 63 |e the julia frac| 000008d0 74 61 6c 2e 0a 41 6c 73 6f 20 74 68 65 20 63 6f |tal..Also the co| 000008e0 6f 72 64 69 6e 61 74 65 73 20 6f 66 20 74 68 69 |ordinates of thi| 000008f0 73 20 70 6f 69 6e 74 20 61 72 65 20 73 68 6f 77 |s point are show| 00000900 6e 2e 20 20 20 20 20 20 20 20 20 20 20 20 20 20 |n. | 00000910 20 20 20 20 20 20 20 20 20 20 0a 54 68 65 20 66 | .The f| 00000920 72 61 63 74 61 6c 73 20 61 72 65 20 63 61 6c 63 |ractals are calc| 00000930 75 6c 61 74 65 64 20 61 63 63 6f 72 64 69 6e 67 |ulated according| 00000940 20 61 20 72 65 63 75 72 73 69 76 65 20 76 65 72 | a recursive ver| 00000950 73 69 6f 6e 20 6f 66 20 74 68 65 0a 69 6e 76 65 |sion of the.inve| 00000960 72 73 65 20 69 74 65 72 61 74 69 6f 6e 20 6d 65 |rse iteration me| 00000970 74 68 6f 64 2e 0a 0a 54 72 61 63 6b 6d 61 6e 0a |thod...Trackman.| 00000980 3d 3d 3d 3d 3d 3d 3d 3d 0a 0a 54 68 69 73 20 70 |========..This p| 00000990 72 6f 67 72 61 6d 20 65 6d 70 6c 6f 79 73 20 61 |rogram employs a| 000009a0 20 6e 6f 76 65 6c 20 74 65 63 68 6e 69 71 75 65 | novel technique| 000009b0 20 74 6f 20 73 70 65 65 64 20 75 70 20 74 68 65 | to speed up the| 000009c0 20 67 65 6e 65 72 61 74 69 6f 6e 20 6f 66 0a 66 | generation of.f| 000009d0 72 61 63 74 61 6c 73 2e 20 54 68 65 20 70 72 6f |ractals. The pro| 000009e0 67 72 61 6d 20 74 72 69 65 73 20 74 6f 20 74 72 |gram tries to tr| 000009f0 61 63 6b 20 6f 6e 6c 79 20 74 68 65 20 70 61 74 |ack only the pat| 00000a00 68 20 62 65 74 77 65 65 6e 20 74 77 6f 20 64 6f |h between two do| 00000a10 6d 61 69 6e 73 0a 6f 66 20 63 6f 6c 6f 75 72 2e |mains.of colour.| 00000a20 20 57 68 65 6e 20 74 68 65 20 62 6f 72 64 65 72 | When the border| 00000a30 20 6f 66 20 74 68 65 73 65 20 64 6f 6d 61 69 6e | of these domain| 00000a40 73 20 69 73 20 63 61 6c 63 75 6c 61 74 65 64 20 |s is calculated | 00000a50 74 68 65 20 72 65 73 74 0a 6f 66 20 74 68 65 20 |the rest.of the | 00000a60 70 6f 69 6e 74 73 20 61 72 65 20 65 61 73 69 6c |points are easil| 00000a70 79 20 66 69 6c 6c 65 64 20 69 6e 2e 20 54 68 69 |y filled in. Thi| 00000a80 73 20 73 63 68 65 6d 65 20 6c 65 61 64 73 20 74 |s scheme leads t| 00000a90 6f 20 73 69 67 6e 69 66 69 63 61 6e 74 0a 74 69 |o significant.ti| 00000aa0 6d 65 20 72 65 64 75 63 74 69 6f 6e 20 73 69 6e |me reduction sin| 00000ab0 63 65 20 6d 75 63 68 20 66 65 77 65 72 20 70 69 |ce much fewer pi| 00000ac0 78 65 6c 73 20 6e 65 65 64 20 74 6f 20 62 65 20 |xels need to be | 00000ad0 63 61 6c 63 75 6c 61 74 65 64 2e 20 45 73 70 65 |calculated. Espe| 00000ae0 63 69 61 6c 6c 79 0a 69 6e 20 68 69 67 68 20 72 |cially.in high r| 00000af0 65 73 6f 6c 75 74 69 6f 6e 20 6d 6f 64 65 73 20 |esolution modes | 00000b00 74 68 65 20 73 70 65 65 64 75 70 20 63 61 6e 20 |the speedup can | 00000b10 62 65 20 67 72 65 61 74 2e 0a 54 68 65 20 70 72 |be great..The pr| 00000b20 6f 67 72 61 6d 20 73 75 70 70 6f 72 74 73 20 74 |ogram supports t| 00000b30 68 65 20 32 35 36 20 63 6f 6c 6f 75 72 20 6d 6f |he 256 colour mo| 00000b40 64 65 73 20 31 33 2c 32 31 20 61 6e 64 20 32 38 |des 13,21 and 28| 00000b50 20 61 6c 73 6f 20 74 68 65 20 31 36 20 63 6f 6c | also the 16 col| 00000b60 6f 75 72 0a 6d 6f 64 65 73 20 39 2c 32 30 2c 32 |our.modes 9,20,2| 00000b70 37 20 61 6e 64 20 33 31 20 61 72 65 20 73 75 70 |7 and 31 are sup| 00000b80 70 6f 72 74 65 64 2e 0a 54 68 65 20 63 6f 6e 74 |ported..The cont| 00000b90 72 6f 6c 20 6f 66 20 74 68 65 20 70 72 6f 67 72 |rol of the progr| 00000ba0 61 6d 20 69 73 20 62 79 20 6d 65 61 6e 73 20 6f |am is by means o| 00000bb0 66 20 74 68 65 20 6b 65 79 62 6f 61 72 64 20 61 |f the keyboard a| 00000bc0 6e 64 20 74 68 65 20 6d 6f 75 73 65 2e 0a 0a 54 |nd the mouse...T| 00000bd0 6f 20 70 65 72 66 6f 72 6d 20 61 20 66 72 61 63 |o perform a frac| 00000be0 74 61 6c 20 67 65 6e 65 72 61 74 69 6f 6e 20 65 |tal generation e| 00000bf0 61 63 68 20 74 69 6d 65 20 61 20 6b 65 79 20 68 |ach time a key h| 00000c00 61 73 20 74 6f 20 62 65 20 70 72 65 73 73 65 64 |as to be pressed| 00000c10 2e 0a 20 4d 20 3a 20 67 65 6e 65 72 61 74 65 73 |.. M : generates| 00000c20 20 61 20 6d 61 6e 64 65 6c 62 72 6f 74 20 66 72 | a mandelbrot fr| 00000c30 61 63 74 61 6c 0a 20 4a 20 3a 20 67 65 6e 65 72 |actal. J : gener| 00000c40 61 74 65 73 20 61 20 6a 75 6c 69 61 20 66 72 61 |ates a julia fra| 00000c50 63 74 61 6c 0a 20 52 20 3a 20 72 65 64 72 61 77 |ctal. R : redraw| 00000c60 73 20 74 68 65 20 69 6e 69 74 69 61 6c 20 66 72 |s the initial fr| 00000c70 61 63 74 61 6c 0a 20 53 20 3a 20 70 72 6f 6d 70 |actal. S : promp| 00000c80 74 73 20 66 6f 72 20 61 20 6e 61 6d 65 20 6f 66 |ts for a name of| 00000c90 20 74 68 65 20 73 63 72 65 65 6e 20 74 6f 20 62 | the screen to b| 00000ca0 65 20 73 61 76 65 64 0a 20 43 20 26 20 44 20 3a |e saved. C & D :| 00000cb0 20 75 73 65 64 20 74 6f 20 63 79 63 6c 65 20 74 | used to cycle t| 00000cc0 68 65 20 63 6f 6c 6f 75 72 20 70 61 6c 65 74 74 |he colour palett| 00000cd0 65 2e 0a 20 56 20 3a 20 74 6f 20 73 77 69 74 63 |e.. V : to switc| 00000ce0 68 20 6f 6e 20 61 6e 64 20 6f 66 66 20 74 68 65 |h on and off the| 00000cf0 20 76 69 64 65 6f 20 44 4d 41 2c 20 74 75 72 6e | video DMA, turn| 00000d00 69 6e 67 20 6f 66 66 20 6d 65 61 6e 73 20 73 68 |ing off means sh| 00000d10 6f 72 74 65 72 20 0a 20 20 20 20 20 67 65 6e 65 |orter . gene| 00000d20 72 61 74 69 6f 6e 20 74 69 6d 65 20 73 69 6e 63 |ration time sinc| 00000d30 65 20 6e 6f 20 44 4d 41 20 6f 76 65 72 68 65 61 |e no DMA overhea| 00000d40 64 20 6f 63 63 75 72 73 2e 0a 20 4e 20 3a 20 75 |d occurs.. N : u| 00000d50 73 65 64 20 74 6f 20 73 77 69 74 63 68 20 74 6f |sed to switch to| 00000d60 20 61 6e 6f 74 68 65 72 20 73 63 72 65 65 6e 20 | another screen | 00000d70 6d 6f 64 65 0a 20 48 20 3a 20 73 68 6f 77 73 20 |mode. H : shows | 00000d80 68 65 6c 70 0a 0a 54 68 65 20 6d 6f 75 73 65 20 |help..The mouse | 00000d90 62 75 74 74 6f 6e 73 20 64 6f 20 74 68 65 20 66 |buttons do the f| 00000da0 6f 6c 6c 6f 77 69 6e 67 20 0a 20 6c 65 66 74 20 |ollowing . left | 00000db0 20 20 3a 20 7a 6f 6f 6d 20 6f 75 74 20 20 20 20 | : zoom out | 00000dc0 20 20 20 20 20 20 20 20 20 20 20 20 20 20 20 0a | .| 00000dd0 20 72 69 67 68 74 20 20 3a 20 7a 6f 6f 6d 20 69 | right : zoom i| 00000de0 6e 0a 20 6d 69 64 64 6c 65 20 3a 20 73 74 61 72 |n. middle : star| 00000df0 74 20 67 65 6e 65 72 61 74 69 6f 6e 0a 20 20 20 |t generation. | 00000e00 20 20 20 20 20 20 20 0a 57 68 65 6e 20 79 6f 75 | .When you| 00000e10 20 61 72 65 20 61 73 6b 65 64 20 74 6f 20 65 6e | are asked to en| 00000e20 74 65 72 20 74 68 65 20 6e 75 6d 62 65 72 20 6f |ter the number o| 00000e30 66 20 69 74 65 72 61 74 69 6f 6e 73 20 70 72 65 |f iterations pre| 00000e40 73 73 69 6e 67 20 52 45 54 55 52 4e 20 0a 63 61 |ssing RETURN .ca| 00000e50 75 73 65 73 20 31 30 30 20 69 74 65 72 61 74 69 |uses 100 iterati| 00000e60 6f 6e 73 20 74 6f 20 62 65 20 73 65 6c 65 63 74 |ons to be select| 00000e70 65 64 2e 0a 59 6f 75 20 63 61 6e 20 69 6e 74 65 |ed..You can inte| 00000e80 72 72 75 70 74 20 74 68 65 20 67 65 6e 65 72 61 |rrupt the genera| 00000e90 74 69 6f 6e 20 62 79 20 70 72 65 73 73 69 6e 67 |tion by pressing| 00000ea0 20 45 53 43 41 50 45 2e 0a 54 68 65 20 69 6e 69 | ESCAPE..The ini| 00000eb0 74 69 61 6c 20 68 65 6c 70 20 63 61 6e 20 62 65 |tial help can be| 00000ec0 20 72 65 6d 6f 76 65 64 20 62 79 20 70 72 65 73 | removed by pres| 00000ed0 73 69 6e 67 20 53 50 41 43 45 2e 0a 0a 41 6e 6f |sing SPACE...Ano| 00000ee0 74 68 65 72 20 66 65 61 74 75 72 65 20 69 73 20 |ther feature is | 00000ef0 69 6e 63 6f 72 70 6f 72 61 74 65 64 20 74 6f 20 |incorporated to | 00000f00 67 65 6e 65 72 61 74 65 20 74 68 65 20 73 70 72 |generate the spr| 00000f10 69 74 65 73 20 74 68 61 74 20 61 72 65 20 75 73 |ites that are us| 00000f20 65 64 0a 69 6e 20 74 68 65 20 70 72 6f 67 72 61 |ed.in the progra| 00000f30 6d 20 4a 75 6c 69 61 6e 20 28 54 68 69 73 20 77 |m Julian (This w| 00000f40 61 73 20 6d 65 61 6e 74 20 74 6f 20 62 65 20 75 |as meant to be u| 00000f50 73 65 64 20 62 79 20 66 6f 72 6d 65 72 20 79 65 |sed by former ye| 00000f60 6c 6c 6f 77 20 70 61 67 65 73 0a 74 79 70 65 72 |llow pages.typer| 00000f70 73 29 2e 20 50 72 65 73 73 69 6e 67 20 53 48 49 |s). Pressing SHI| 00000f80 46 54 20 51 20 69 6e 20 74 68 65 20 6d 6f 64 65 |FT Q in the mode| 00000f90 73 20 31 33 20 61 6e 64 20 32 31 20 63 61 75 73 |s 13 and 21 caus| 00000fa0 65 73 20 74 68 65 73 65 20 66 72 61 63 74 61 6c |es these fractal| 00000fb0 73 0a 74 6f 20 62 65 20 73 61 76 65 64 2e 0a 0a |s.to be saved...| 00000fc0 57 68 65 6e 20 73 77 69 74 63 68 69 6e 67 20 74 |When switching t| 00000fd0 6f 20 6a 75 6c 69 61 2d 67 65 6e 65 72 61 74 69 |o julia-generati| 00000fe0 6f 6e 20 74 68 65 20 63 75 72 72 65 6e 74 20 6d |on the current m| 00000ff0 61 6e 64 65 6c 62 72 6f 74 20 73 63 72 65 65 6e |andelbrot screen| 00001000 20 69 73 20 73 61 76 65 64 2e 0a 57 68 65 6e 20 | is saved..When | 00001010 73 77 69 74 63 68 69 6e 67 20 62 61 63 6b 20 77 |switching back w| 00001020 69 74 68 20 27 4d 27 20 69 74 20 69 73 20 72 65 |ith 'M' it is re| 00001030 6c 6f 61 64 65 64 2e 0a 53 6f 20 65 6e 73 75 72 |loaded..So ensur| 00001040 65 20 74 68 61 74 20 61 20 64 69 73 63 20 69 73 |e that a disc is| 00001050 20 69 6e 73 65 72 74 65 64 20 77 68 65 6e 20 79 | inserted when y| 00001060 6f 75 20 6f 6e 6c 79 20 68 61 76 65 20 61 20 66 |ou only have a f| 00001070 6c 6f 70 70 79 2d 64 72 69 76 65 2e 0a 53 61 76 |loppy-drive..Sav| 00001080 69 6e 67 20 74 68 65 20 73 63 72 65 65 6e 20 74 |ing the screen t| 00001090 6f 20 66 6c 6f 70 70 79 20 6d 61 79 20 61 63 74 |o floppy may act| 000010a0 75 61 6c 6c 79 20 62 65 20 73 6c 6f 77 65 72 20 |ually be slower | 000010b0 74 68 61 6e 20 72 65 64 72 61 77 69 6e 67 2e 0a |than redrawing..| 000010c0 53 6f 20 79 6f 75 20 62 65 74 74 65 72 20 73 65 |So you better se| 000010d0 74 20 74 68 65 20 66 69 6c 6c 69 6e 67 20 73 79 |t the filling sy| 000010e0 73 74 65 6e 20 74 6f 20 52 41 4d 20 77 69 74 68 |sten to RAM with| 000010f0 20 2a 52 41 4d 20 61 6e 64 20 6d 61 6b 65 20 69 | *RAM and make i| 00001100 74 20 62 69 67 0a 65 6e 6f 75 67 68 2e 20 4f 72 |t big.enough. Or| 00001110 20 79 6f 75 20 63 61 6e 20 73 65 74 20 74 68 65 | you can set the| 00001120 20 76 61 72 69 61 62 6c 65 20 27 73 61 76 65 27 | variable 'save'| 00001130 20 6f 6e 20 74 68 65 20 74 68 69 72 64 20 6c 69 | on the third li| 00001140 6e 65 20 74 6f 20 66 61 6c 73 65 2e 0a 0a 54 68 |ne to false...Th| 00001150 65 20 70 72 6f 67 72 61 6d 20 75 73 65 73 20 61 |e program uses a| 00001160 20 66 61 69 72 6c 79 20 62 69 67 20 63 68 75 6e | fairly big chun| 00001170 6b 20 6f 66 20 6d 65 6d 6f 72 79 20 6f 6e 20 74 |k of memory on t| 00001180 6f 70 20 6f 70 20 74 68 65 20 73 79 73 74 65 6d |op op the system| 00001190 20 73 74 61 63 6b 2e 0a 54 68 69 73 20 61 6d 6f | stack..This amo| 000011a0 75 6e 74 20 6f 66 20 6d 65 6d 6f 72 79 20 69 6e |unt of memory in| 000011b0 63 72 65 61 73 65 73 20 77 69 74 68 20 74 68 65 |creases with the| 000011c0 20 63 6f 6d 70 6c 65 78 69 74 79 20 6f 66 20 74 | complexity of t| 000011d0 68 65 20 66 72 61 63 74 61 6c 2e 0a 49 74 20 69 |he fractal..It i| 000011e0 73 20 74 68 65 72 65 66 6f 72 65 20 61 64 76 69 |s therefore advi| 000011f0 73 61 62 6c 65 20 74 6f 20 61 6c 6c 6f 63 61 74 |sable to allocat| 00001200 65 20 61 74 20 6c 65 61 73 74 20 33 30 30 6b 62 |e at least 300kb| 00001210 20 62 65 66 6f 72 65 20 73 74 61 72 74 69 6e 67 | before starting| 00001220 20 74 68 65 0a 70 72 6f 67 72 61 6d 2e 0a 20 20 | the.program.. | 00001230 20 20 20 20 20 20 20 20 20 20 20 20 20 20 20 20 | | 00001240 0a 53 74 72 69 6e 67 7a 0a 3d 3d 3d 3d 3d 3d 3d |.Stringz.=======| 00001250 0a 0a 54 68 69 73 20 69 73 20 61 6e 20 69 6d 70 |..This is an imp| 00001260 72 6f 76 65 64 20 76 65 72 73 69 6f 6e 20 6f 66 |roved version of| 00001270 20 6d 79 20 66 6f 72 6d 65 72 20 53 54 52 49 4e | my former STRIN| 00001280 47 20 70 72 6f 67 72 61 6d 2e 0a 45 6e 68 61 6e |G program..Enhan| 00001290 63 65 6d 65 6e 74 73 20 61 72 65 3a 20 42 65 74 |cements are: Bet| 000012a0 74 65 72 20 6d 6f 75 73 65 20 63 6f 6e 74 72 6f |ter mouse contro| 000012b0 6c 2c 20 6e 69 63 65 72 20 63 6f 6c 6f 75 72 20 |l, nicer colour | 000012c0 61 6e 64 20 6d 6f 73 74 20 69 6d 70 6f 72 74 61 |and most importa| 000012d0 6e 74 0a 6e 6f 20 6d 6f 72 65 20 76 65 72 74 69 |nt.no more verti| 000012e0 63 61 6c 20 67 61 70 73 20 62 65 74 77 65 65 6e |cal gaps between| 000012f0 20 70 69 78 65 6c 73 2e 0a 43 6c 69 63 6b 69 6e | pixels..Clickin| 00001300 67 20 73 65 6c 65 63 74 20 77 69 70 65 73 20 74 |g select wipes t| 00001310 68 65 20 73 63 72 65 65 6e 20 61 6e 64 20 72 65 |he screen and re| 00001320 73 74 61 72 74 73 2c 20 63 6c 69 63 6b 69 6e 67 |starts, clicking| 00001330 20 61 64 6a 75 73 74 20 65 6e 64 73 20 0a 74 68 | adjust ends .th| 00001340 65 20 70 72 6f 67 72 61 6d 20 20 20 20 20 20 20 |e program | 00001350 20 20 20 20 20 20 20 20 20 20 20 20 20 20 20 20 | | * 00001380 20 20 20 20 0a 57 69 74 68 20 74 68 65 20 76 61 | .With the va| 00001390 72 69 61 62 6c 65 73 20 27 70 72 6f 70 27 20 61 |riables 'prop' a| 000013a0 6e 64 20 27 64 61 6d 70 27 20 69 6e 20 74 68 65 |nd 'damp' in the| 000013b0 20 72 61 6e 67 65 20 30 2d 33 31 20 79 6f 75 20 | range 0-31 you | 000013c0 63 61 6e 20 73 65 74 20 0a 74 68 65 20 70 72 6f |can set .the pro| 000013d0 70 61 67 61 74 69 6f 6e 20 73 70 65 65 64 20 61 |pagation speed a| 000013e0 6e 64 20 64 61 6d 70 69 6e 67 20 6f 66 20 74 68 |nd damping of th| 000013f0 65 20 77 61 76 65 2e 0a 41 72 6d 33 20 75 73 65 |e wave..Arm3 use| 00001400 72 73 20 6d 61 79 20 77 69 73 68 20 74 6f 20 75 |rs may wish to u| 00001410 73 65 20 74 68 69 73 20 70 72 6f 67 72 61 6d 20 |se this program | 00001420 69 6e 20 6d 6f 64 65 20 32 31 20 69 6e 73 74 65 |in mode 21 inste| 00001430 61 64 20 6f 66 20 6d 6f 64 65 20 31 33 2e 0a 54 |ad of mode 13..T| 00001440 6f 20 61 63 68 69 65 76 65 20 74 68 69 73 20 79 |o achieve this y| 00001450 6f 75 20 63 61 6e 20 73 65 74 20 74 68 65 20 76 |ou can set the v| 00001460 61 72 69 61 62 6c 65 20 27 68 69 67 68 27 20 6f |ariable 'high' o| 00001470 6e 20 74 68 65 20 74 68 69 72 64 20 6c 69 6e 65 |n the third line| 00001480 20 74 6f 20 54 52 55 45 2e 0a | to TRUE..| 0000148a
.