Home » Archimedes archive » Acorn User » AU 1998-04 A.adf » Regulars » StarInfo/Stratton/README
StarInfo/Stratton/README
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 1998-04 A.adf » Regulars |
| Filename: | StarInfo/Stratton/README |
| Read OK: | ✔ |
| File size: | 05C1 bytes |
| Load address: | 0000 |
| Exec address: | 0000 |
File contents
Dear *info, Spiro is a spirograph generator that I wrote for a programming competition between myself and a friend of mine at school. He used a 25MHz 486 and I used an A5000. I think you can guess the result of the competition. Spiro requires you to specify five values. These are: 1) The size of the hole at the centre of the spirograph 2) The number of cycles of the line 3) How sharp the line curves 4) The number of times the colours repeat in each cycle 5) The type of pattern This probably sounds like a load of jibberish, but to understand the values you need to understand the way I have generated the patterns. An easier way to find out what they do is to play around with them. Try 10, 101, 64, 3, and try pattern types one to four. After this try other values for all the settings. If you press return, the same value will be entered as you entered the time before. In a conventional (paper) spirograph you cannot get such wide range of patterns as is avaiable in this program. Of the four pattern types, only one can be generated. A circle within another circle must move the same way as they are rotating. This is not so in this program, and allows interesting effects when a pattern loops in on itself. NOTE: Spiro likes mode 27, but can be persuaded to run in mode 12. Changing the mode instruction from mode 27 to mode 12 tends to help this. I am: Graham Stratton (15) 8 Holme Road Ramsey St Mary's HUNTINGDON Cambridgeshire PE17 1SS
00000000 44 65 61 72 20 2a 69 6e 66 6f 2c 0a 20 20 53 70 |Dear *info,. Sp| 00000010 69 72 6f 20 69 73 20 61 20 73 70 69 72 6f 67 72 |iro is a spirogr| 00000020 61 70 68 20 67 65 6e 65 72 61 74 6f 72 20 74 68 |aph generator th| 00000030 61 74 20 49 20 77 72 6f 74 65 20 66 6f 72 20 61 |at I wrote for a| 00000040 20 70 72 6f 67 72 61 6d 6d 69 6e 67 20 63 6f 6d | programming com| 00000050 70 65 74 69 74 69 6f 6e 20 62 65 74 77 65 65 6e |petition between| 00000060 20 6d 79 73 65 6c 66 20 61 6e 64 20 61 20 66 72 | myself and a fr| 00000070 69 65 6e 64 20 6f 66 20 6d 69 6e 65 20 61 74 20 |iend of mine at | 00000080 73 63 68 6f 6f 6c 2e 20 20 48 65 20 75 73 65 64 |school. He used| 00000090 20 61 20 32 35 4d 48 7a 20 34 38 36 20 61 6e 64 | a 25MHz 486 and| 000000a0 20 49 20 75 73 65 64 20 61 6e 20 41 35 30 30 30 | I used an A5000| 000000b0 2e 20 20 49 20 74 68 69 6e 6b 20 79 6f 75 20 63 |. I think you c| 000000c0 61 6e 20 67 75 65 73 73 20 74 68 65 20 72 65 73 |an guess the res| 000000d0 75 6c 74 20 6f 66 20 74 68 65 20 63 6f 6d 70 65 |ult of the compe| 000000e0 74 69 74 69 6f 6e 2e 0a 0a 20 20 53 70 69 72 6f |tition... Spiro| 000000f0 20 72 65 71 75 69 72 65 73 20 79 6f 75 20 74 6f | requires you to| 00000100 20 73 70 65 63 69 66 79 20 66 69 76 65 20 76 61 | specify five va| 00000110 6c 75 65 73 2e 20 20 54 68 65 73 65 20 61 72 65 |lues. These are| 00000120 3a 0a 31 29 20 54 68 65 20 73 69 7a 65 20 6f 66 |:.1) The size of| 00000130 20 74 68 65 20 68 6f 6c 65 20 61 74 20 74 68 65 | the hole at the| 00000140 20 63 65 6e 74 72 65 20 6f 66 20 74 68 65 20 73 | centre of the s| 00000150 70 69 72 6f 67 72 61 70 68 0a 32 29 20 54 68 65 |pirograph.2) The| 00000160 20 6e 75 6d 62 65 72 20 6f 66 20 63 79 63 6c 65 | number of cycle| 00000170 73 20 6f 66 20 74 68 65 20 6c 69 6e 65 0a 33 29 |s of the line.3)| 00000180 20 48 6f 77 20 73 68 61 72 70 20 74 68 65 20 6c | How sharp the l| 00000190 69 6e 65 20 63 75 72 76 65 73 0a 34 29 20 54 68 |ine curves.4) Th| 000001a0 65 20 6e 75 6d 62 65 72 20 6f 66 20 74 69 6d 65 |e number of time| 000001b0 73 20 74 68 65 20 63 6f 6c 6f 75 72 73 20 72 65 |s the colours re| 000001c0 70 65 61 74 20 69 6e 20 65 61 63 68 20 63 79 63 |peat in each cyc| 000001d0 6c 65 0a 35 29 20 54 68 65 20 74 79 70 65 20 6f |le.5) The type o| 000001e0 66 20 70 61 74 74 65 72 6e 0a 0a 20 20 54 68 69 |f pattern.. Thi| 000001f0 73 20 70 72 6f 62 61 62 6c 79 20 73 6f 75 6e 64 |s probably sound| 00000200 73 20 6c 69 6b 65 20 61 20 6c 6f 61 64 20 6f 66 |s like a load of| 00000210 20 6a 69 62 62 65 72 69 73 68 2c 20 62 75 74 20 | jibberish, but | 00000220 74 6f 20 75 6e 64 65 72 73 74 61 6e 64 20 74 68 |to understand th| 00000230 65 20 76 61 6c 75 65 73 20 79 6f 75 20 6e 65 65 |e values you nee| 00000240 64 20 74 6f 20 75 6e 64 65 72 73 74 61 6e 64 20 |d to understand | 00000250 74 68 65 20 77 61 79 20 49 20 68 61 76 65 20 67 |the way I have g| 00000260 65 6e 65 72 61 74 65 64 20 74 68 65 20 70 61 74 |enerated the pat| 00000270 74 65 72 6e 73 2e 20 20 41 6e 20 65 61 73 69 65 |terns. An easie| 00000280 72 20 77 61 79 20 74 6f 20 66 69 6e 64 20 6f 75 |r way to find ou| 00000290 74 20 77 68 61 74 20 74 68 65 79 20 64 6f 20 69 |t what they do i| 000002a0 73 20 74 6f 20 70 6c 61 79 20 61 72 6f 75 6e 64 |s to play around| 000002b0 20 77 69 74 68 20 74 68 65 6d 2e 20 20 54 72 79 | with them. Try| 000002c0 20 31 30 2c 20 31 30 31 2c 20 36 34 2c 20 33 2c | 10, 101, 64, 3,| 000002d0 20 61 6e 64 20 74 72 79 20 70 61 74 74 65 72 6e | and try pattern| 000002e0 20 74 79 70 65 73 20 6f 6e 65 20 74 6f 20 66 6f | types one to fo| 000002f0 75 72 2e 20 20 41 66 74 65 72 20 74 68 69 73 20 |ur. After this | 00000300 74 72 79 20 6f 74 68 65 72 20 76 61 6c 75 65 73 |try other values| 00000310 20 66 6f 72 20 61 6c 6c 20 74 68 65 20 73 65 74 | for all the set| 00000320 74 69 6e 67 73 2e 20 20 49 66 20 79 6f 75 20 70 |tings. If you p| 00000330 72 65 73 73 20 72 65 74 75 72 6e 2c 20 74 68 65 |ress return, the| 00000340 20 73 61 6d 65 20 76 61 6c 75 65 20 77 69 6c 6c | same value will| 00000350 20 62 65 20 65 6e 74 65 72 65 64 20 61 73 20 79 | be entered as y| 00000360 6f 75 20 65 6e 74 65 72 65 64 20 74 68 65 20 74 |ou entered the t| 00000370 69 6d 65 20 62 65 66 6f 72 65 2e 0a 20 20 49 6e |ime before.. In| 00000380 20 61 20 63 6f 6e 76 65 6e 74 69 6f 6e 61 6c 20 | a conventional | 00000390 28 70 61 70 65 72 29 20 73 70 69 72 6f 67 72 61 |(paper) spirogra| 000003a0 70 68 20 79 6f 75 20 63 61 6e 6e 6f 74 20 67 65 |ph you cannot ge| 000003b0 74 20 73 75 63 68 20 77 69 64 65 20 72 61 6e 67 |t such wide rang| 000003c0 65 20 6f 66 20 70 61 74 74 65 72 6e 73 20 61 73 |e of patterns as| 000003d0 20 69 73 20 61 76 61 69 61 62 6c 65 20 69 6e 20 | is avaiable in | 000003e0 74 68 69 73 20 70 72 6f 67 72 61 6d 2e 20 20 4f |this program. O| 000003f0 66 20 74 68 65 20 66 6f 75 72 20 70 61 74 74 65 |f the four patte| 00000400 72 6e 20 74 79 70 65 73 2c 20 6f 6e 6c 79 20 6f |rn types, only o| 00000410 6e 65 20 63 61 6e 20 62 65 20 67 65 6e 65 72 61 |ne can be genera| 00000420 74 65 64 2e 20 20 41 20 63 69 72 63 6c 65 20 77 |ted. A circle w| 00000430 69 74 68 69 6e 20 61 6e 6f 74 68 65 72 20 63 69 |ithin another ci| 00000440 72 63 6c 65 20 6d 75 73 74 20 6d 6f 76 65 20 74 |rcle must move t| 00000450 68 65 20 73 61 6d 65 20 77 61 79 20 61 73 20 74 |he same way as t| 00000460 68 65 79 20 61 72 65 20 72 6f 74 61 74 69 6e 67 |hey are rotating| 00000470 2e 20 20 54 68 69 73 20 69 73 20 6e 6f 74 20 73 |. This is not s| 00000480 6f 20 69 6e 20 74 68 69 73 20 70 72 6f 67 72 61 |o in this progra| 00000490 6d 2c 20 61 6e 64 20 61 6c 6c 6f 77 73 20 69 6e |m, and allows in| 000004a0 74 65 72 65 73 74 69 6e 67 20 65 66 66 65 63 74 |teresting effect| 000004b0 73 20 77 68 65 6e 20 61 20 70 61 74 74 65 72 6e |s when a pattern| 000004c0 20 6c 6f 6f 70 73 20 69 6e 20 6f 6e 20 69 74 73 | loops in on its| 000004d0 65 6c 66 2e 0a 0a 20 4e 4f 54 45 3a 20 53 70 69 |elf... NOTE: Spi| 000004e0 72 6f 20 6c 69 6b 65 73 20 6d 6f 64 65 20 32 37 |ro likes mode 27| 000004f0 2c 20 62 75 74 20 63 61 6e 20 62 65 20 70 65 72 |, but can be per| 00000500 73 75 61 64 65 64 20 74 6f 20 72 75 6e 20 69 6e |suaded to run in| 00000510 20 6d 6f 64 65 20 31 32 2e 20 20 43 68 61 6e 67 | mode 12. Chang| 00000520 69 6e 67 20 74 68 65 20 6d 6f 64 65 20 69 6e 73 |ing the mode ins| 00000530 74 72 75 63 74 69 6f 6e 20 66 72 6f 6d 20 6d 6f |truction from mo| 00000540 64 65 20 32 37 20 74 6f 20 6d 6f 64 65 20 31 32 |de 27 to mode 12| 00000550 20 74 65 6e 64 73 20 74 6f 20 68 65 6c 70 20 74 | tends to help t| 00000560 68 69 73 2e 0a 0a 49 20 61 6d 3a 0a 47 72 61 68 |his...I am:.Grah| 00000570 61 6d 20 53 74 72 61 74 74 6f 6e 20 28 31 35 29 |am Stratton (15)| 00000580 0a 38 20 48 6f 6c 6d 65 20 52 6f 61 64 0a 52 61 |.8 Holme Road.Ra| 00000590 6d 73 65 79 20 53 74 20 4d 61 72 79 27 73 0a 48 |msey St Mary's.H| 000005a0 55 4e 54 49 4e 47 44 4f 4e 0a 43 61 6d 62 72 69 |UNTINGDON.Cambri| 000005b0 64 67 65 73 68 69 72 65 0a 50 45 31 37 20 31 53 |dgeshire.PE17 1S| 000005c0 53 |S| 000005c1
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