Home » Archimedes archive » Archimedes World » AW-1992-03.adf » AWMar92 » !AWMar92/Goodies/StarGazer/!stargazer/info
!AWMar92/Goodies/StarGazer/!stargazer/info
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 » Archimedes World » AW-1992-03.adf » AWMar92 |
| Filename: | !AWMar92/Goodies/StarGazer/!stargazer/info |
| Read OK: | ✔ |
| File size: | 1265 bytes |
| Load address: | 0000 |
| Exec address: | 0000 |
File contents
Notes on !Stargazer Stargazer is an interactive star plotter, with support for the major objects in our solar system. It works using the internal system clock to provide real time update of a start viewing window. The time can be changed using the Acorn !Alarm application to look at past and future star maps. The new position of every star is calculated once a minute in the background. Stargazer is intended as a simple interactive learning tool to help beginners in astronomy learn about the planets and the stars. The most powerful and important feature is the constellation identification aid, where groups of stars are connected with dotted lines to give a representation of the name of the constellation they are part of. This facility helps to identify and remember constellation patterns in the sky. The star database is in the form of an editable textual database, which is interpreted by the application when it is first installed on the icon bar. This allows more advanced users to edit the database to include new objects. The star database contains the locations of over 1300 objects, down to magnitude 5 (the limit of visibility to the naked eye) for epoch 2000 (their exact position in the year 2000ad). Note that the greek alphabet for entry purposes is "abgdezh0iklmnxoprstvqfcw" for alpha, beta gamma etc. 'means literal. Strings are allowed in the database but are not implemented in !Stargazer. Stargazer is a RISCOS application installing itself on the Icon bar and utilising mouse, pointer and menu operations to provide its facilities. It interacts with the !Help application to give user help when required. There are two main menus, one of which is presented when the user clicks on the stargazer icon, and one which is available when the "view" window is opened. These are briefly described below. Icon menu The icon menu provides an info box and four menu options. New place allows the user to specify the observers longitude and latitude. It is initialised to longitude 0d0mE and latitude 52d0mN which is centred around Cambridge (where else) but should suit the south of England. To see the stars that are only visible from the southern hemisphere you could try 52d0mS!. The "d" and "m" are short for degrees and minutes (in lower case) and the "N","S" (for latitude) or "E","W" (in upper-case) specify positive or negative directions. New time forces a recalculation of all object positions taking the present clock setting. Show Sky duplicates the left button click on the icon, and opens the view window. Quit is self explanatory View window menu The view window menu provides extra view related facilities Find object attempts to centre the view around the chosen object. Sub-menus are used to choose the type of object, and then specify a particular occurrence. Note that star names must match the names after the equals signs in the database, including the case; these generally start with an upper case letter. The constellation finder will find the first star in the constellation, generally Alpha. Show consts will toggle the constellation identification option on or off. Zoom in and zoom out allow the user to user to optimise the view for detail. Fainter stars tend to disappear as you zoom out (and brighter stars get dimmer), to prevent the view from becoming confused. Simulate allows you to step through a simulated sequence of star positions, rather like a fast forward button. This is very processor intensive, so duration and step sizes can be varied. It provides an insight into the way the postion of the stars change during the evening. All the usual RISCOS window buttons apply to the view window to allow resizing, scrolling, front and window close. The displayed objects are archimedes sprites. The planets are designed to be reasonably recognisable, but not representative in terms of their magnitude. The program is written completely in BBC basic with two libraries for sprite and windows handling. These could be extracted and used with other programs. Some routines (specifically the redrawing and database interpeter) have been optimised to make the program more usable, and so may be less readable, but the operation of the program can be seen. Sorry about the "majic numbers" by the way. Happy stargazing! The program has successfully been compiled using the Silicon Vision RiscBasic Compiler, which speeds up drawing alot, but unfortunately increased the calculation time. Suggestions for enhancements/bug fixes etc to: Steve Ellwood (BSc) Castle Farm Hasse Road Soham, Near Ely Cambridgeshire P.S. Thanks to EO Computer LTD (Cambridge) for the use of the Acorn R140 with TAXAN multisync monitor.
00000000 4e 6f 74 65 73 20 6f 6e 20 21 53 74 61 72 67 61 |Notes on !Starga| 00000010 7a 65 72 0a 0a 53 74 61 72 67 61 7a 65 72 20 69 |zer..Stargazer i| 00000020 73 20 61 6e 20 69 6e 74 65 72 61 63 74 69 76 65 |s an interactive| 00000030 20 73 74 61 72 20 70 6c 6f 74 74 65 72 2c 20 77 | star plotter, w| 00000040 69 74 68 20 73 75 70 70 6f 72 74 20 66 6f 72 20 |ith support for | 00000050 74 68 65 0a 6d 61 6a 6f 72 20 6f 62 6a 65 63 74 |the.major object| 00000060 73 20 69 6e 20 6f 75 72 20 73 6f 6c 61 72 20 73 |s in our solar s| 00000070 79 73 74 65 6d 2e 20 20 49 74 20 77 6f 72 6b 73 |ystem. It works| 00000080 20 75 73 69 6e 67 20 74 68 65 20 69 6e 74 65 72 | using the inter| 00000090 6e 61 6c 0a 73 79 73 74 65 6d 20 63 6c 6f 63 6b |nal.system clock| 000000a0 20 74 6f 20 70 72 6f 76 69 64 65 20 72 65 61 6c | to provide real| 000000b0 20 74 69 6d 65 20 75 70 64 61 74 65 20 6f 66 20 | time update of | 000000c0 61 20 73 74 61 72 74 20 76 69 65 77 69 6e 67 20 |a start viewing | 000000d0 77 69 6e 64 6f 77 2e 0a 54 68 65 20 74 69 6d 65 |window..The time| 000000e0 20 63 61 6e 20 62 65 20 63 68 61 6e 67 65 64 20 | can be changed | 000000f0 75 73 69 6e 67 20 74 68 65 20 41 63 6f 72 6e 20 |using the Acorn | 00000100 21 41 6c 61 72 6d 20 61 70 70 6c 69 63 61 74 69 |!Alarm applicati| 00000110 6f 6e 20 74 6f 20 6c 6f 6f 6b 20 0a 61 74 20 70 |on to look .at p| 00000120 61 73 74 20 61 6e 64 20 66 75 74 75 72 65 20 73 |ast and future s| 00000130 74 61 72 20 6d 61 70 73 2e 20 20 54 68 65 20 6e |tar maps. The n| 00000140 65 77 20 70 6f 73 69 74 69 6f 6e 20 6f 66 20 65 |ew position of e| 00000150 76 65 72 79 20 73 74 61 72 20 69 73 0a 63 61 6c |very star is.cal| 00000160 63 75 6c 61 74 65 64 20 6f 6e 63 65 20 61 20 6d |culated once a m| 00000170 69 6e 75 74 65 20 69 6e 20 74 68 65 20 62 61 63 |inute in the bac| 00000180 6b 67 72 6f 75 6e 64 2e 0a 0a 53 74 61 72 67 61 |kground...Starga| 00000190 7a 65 72 20 69 73 20 69 6e 74 65 6e 64 65 64 20 |zer is intended | 000001a0 61 73 20 61 20 73 69 6d 70 6c 65 20 69 6e 74 65 |as a simple inte| 000001b0 72 61 63 74 69 76 65 20 6c 65 61 72 6e 69 6e 67 |ractive learning| 000001c0 20 74 6f 6f 6c 20 74 6f 20 68 65 6c 70 0a 62 65 | tool to help.be| 000001d0 67 69 6e 6e 65 72 73 20 69 6e 20 61 73 74 72 6f |ginners in astro| 000001e0 6e 6f 6d 79 20 6c 65 61 72 6e 20 61 62 6f 75 74 |nomy learn about| 000001f0 20 74 68 65 20 70 6c 61 6e 65 74 73 20 61 6e 64 | the planets and| 00000200 20 74 68 65 20 73 74 61 72 73 2e 20 20 54 68 65 | the stars. The| 00000210 20 6d 6f 73 74 0a 70 6f 77 65 72 66 75 6c 20 61 | most.powerful a| 00000220 6e 64 20 69 6d 70 6f 72 74 61 6e 74 20 66 65 61 |nd important fea| 00000230 74 75 72 65 20 69 73 20 74 68 65 20 63 6f 6e 73 |ture is the cons| 00000240 74 65 6c 6c 61 74 69 6f 6e 20 69 64 65 6e 74 69 |tellation identi| 00000250 66 69 63 61 74 69 6f 6e 20 61 69 64 2c 0a 77 68 |fication aid,.wh| 00000260 65 72 65 20 67 72 6f 75 70 73 20 6f 66 20 73 74 |ere groups of st| 00000270 61 72 73 20 61 72 65 20 63 6f 6e 6e 65 63 74 65 |ars are connecte| 00000280 64 20 77 69 74 68 20 64 6f 74 74 65 64 20 6c 69 |d with dotted li| 00000290 6e 65 73 20 74 6f 20 67 69 76 65 20 61 0a 72 65 |nes to give a.re| 000002a0 70 72 65 73 65 6e 74 61 74 69 6f 6e 20 6f 66 20 |presentation of | 000002b0 74 68 65 20 6e 61 6d 65 20 6f 66 20 74 68 65 20 |the name of the | 000002c0 63 6f 6e 73 74 65 6c 6c 61 74 69 6f 6e 20 74 68 |constellation th| 000002d0 65 79 20 61 72 65 20 70 61 72 74 20 6f 66 2e 0a |ey are part of..| 000002e0 54 68 69 73 20 66 61 63 69 6c 69 74 79 20 68 65 |This facility he| 000002f0 6c 70 73 20 74 6f 20 69 64 65 6e 74 69 66 79 20 |lps to identify | 00000300 61 6e 64 20 72 65 6d 65 6d 62 65 72 20 63 6f 6e |and remember con| 00000310 73 74 65 6c 6c 61 74 69 6f 6e 20 70 61 74 74 65 |stellation patte| 00000320 72 6e 73 0a 69 6e 20 74 68 65 20 73 6b 79 2e 0a |rns.in the sky..| 00000330 0a 54 68 65 20 73 74 61 72 20 64 61 74 61 62 61 |.The star databa| 00000340 73 65 20 69 73 20 69 6e 20 74 68 65 20 66 6f 72 |se is in the for| 00000350 6d 20 6f 66 20 61 6e 20 65 64 69 74 61 62 6c 65 |m of an editable| 00000360 20 74 65 78 74 75 61 6c 20 64 61 74 61 62 61 73 | textual databas| 00000370 65 2c 0a 77 68 69 63 68 20 69 73 20 69 6e 74 65 |e,.which is inte| 00000380 72 70 72 65 74 65 64 20 62 79 20 74 68 65 20 61 |rpreted by the a| 00000390 70 70 6c 69 63 61 74 69 6f 6e 20 77 68 65 6e 20 |pplication when | 000003a0 69 74 20 69 73 20 66 69 72 73 74 20 69 6e 73 74 |it is first inst| 000003b0 61 6c 6c 65 64 0a 6f 6e 20 74 68 65 20 69 63 6f |alled.on the ico| 000003c0 6e 20 62 61 72 2e 20 20 54 68 69 73 20 61 6c 6c |n bar. This all| 000003d0 6f 77 73 20 6d 6f 72 65 20 61 64 76 61 6e 63 65 |ows more advance| 000003e0 64 20 75 73 65 72 73 20 74 6f 20 65 64 69 74 20 |d users to edit | 000003f0 74 68 65 20 64 61 74 61 62 61 73 65 0a 74 6f 20 |the database.to | 00000400 69 6e 63 6c 75 64 65 20 6e 65 77 20 6f 62 6a 65 |include new obje| 00000410 63 74 73 2e 20 20 54 68 65 20 73 74 61 72 20 64 |cts. The star d| 00000420 61 74 61 62 61 73 65 20 63 6f 6e 74 61 69 6e 73 |atabase contains| 00000430 20 74 68 65 20 6c 6f 63 61 74 69 6f 6e 73 20 6f | the locations o| 00000440 66 20 6f 76 65 72 0a 31 33 30 30 20 6f 62 6a 65 |f over.1300 obje| 00000450 63 74 73 2c 20 64 6f 77 6e 20 74 6f 20 6d 61 67 |cts, down to mag| 00000460 6e 69 74 75 64 65 20 35 20 28 74 68 65 20 6c 69 |nitude 5 (the li| 00000470 6d 69 74 20 6f 66 20 76 69 73 69 62 69 6c 69 74 |mit of visibilit| 00000480 79 20 74 6f 20 74 68 65 20 6e 61 6b 65 64 0a 65 |y to the naked.e| 00000490 79 65 29 20 66 6f 72 20 65 70 6f 63 68 20 32 30 |ye) for epoch 20| 000004a0 30 30 20 28 74 68 65 69 72 20 65 78 61 63 74 20 |00 (their exact | 000004b0 70 6f 73 69 74 69 6f 6e 20 69 6e 20 74 68 65 20 |position in the | 000004c0 79 65 61 72 20 32 30 30 30 61 64 29 2e 0a 4e 6f |year 2000ad)..No| 000004d0 74 65 20 74 68 61 74 20 74 68 65 20 67 72 65 65 |te that the gree| 000004e0 6b 20 61 6c 70 68 61 62 65 74 20 66 6f 72 20 65 |k alphabet for e| 000004f0 6e 74 72 79 20 70 75 72 70 6f 73 65 73 20 69 73 |ntry purposes is| 00000500 20 0a 22 61 62 67 64 65 7a 68 30 69 6b 6c 6d 6e | ."abgdezh0iklmn| 00000510 78 6f 70 72 73 74 76 71 66 63 77 22 20 66 6f 72 |xoprstvqfcw" for| 00000520 20 61 6c 70 68 61 2c 20 62 65 74 61 20 67 61 6d | alpha, beta gam| 00000530 6d 61 20 65 74 63 2e 20 27 6d 65 61 6e 73 20 6c |ma etc. 'means l| 00000540 69 74 65 72 61 6c 2e 0a 53 74 72 69 6e 67 73 20 |iteral..Strings | 00000550 61 72 65 20 61 6c 6c 6f 77 65 64 20 69 6e 20 74 |are allowed in t| 00000560 68 65 20 64 61 74 61 62 61 73 65 20 62 75 74 20 |he database but | 00000570 61 72 65 20 6e 6f 74 20 69 6d 70 6c 65 6d 65 6e |are not implemen| 00000580 74 65 64 20 69 6e 20 21 53 74 61 72 67 61 7a 65 |ted in !Stargaze| 00000590 72 2e 20 20 0a 0a 53 74 61 72 67 61 7a 65 72 20 |r. ..Stargazer | 000005a0 69 73 20 61 20 52 49 53 43 4f 53 20 61 70 70 6c |is a RISCOS appl| 000005b0 69 63 61 74 69 6f 6e 20 69 6e 73 74 61 6c 6c 69 |ication installi| 000005c0 6e 67 20 69 74 73 65 6c 66 20 6f 6e 20 74 68 65 |ng itself on the| 000005d0 20 49 63 6f 6e 20 62 61 72 20 61 6e 64 0a 75 74 | Icon bar and.ut| 000005e0 69 6c 69 73 69 6e 67 20 6d 6f 75 73 65 2c 20 70 |ilising mouse, p| 000005f0 6f 69 6e 74 65 72 20 61 6e 64 20 6d 65 6e 75 20 |ointer and menu | 00000600 6f 70 65 72 61 74 69 6f 6e 73 20 74 6f 20 70 72 |operations to pr| 00000610 6f 76 69 64 65 20 69 74 73 20 66 61 63 69 6c 69 |ovide its facili| 00000620 74 69 65 73 2e 0a 49 74 20 69 6e 74 65 72 61 63 |ties..It interac| 00000630 74 73 20 77 69 74 68 20 74 68 65 20 21 48 65 6c |ts with the !Hel| 00000640 70 20 61 70 70 6c 69 63 61 74 69 6f 6e 20 74 6f |p application to| 00000650 20 67 69 76 65 20 75 73 65 72 20 68 65 6c 70 20 | give user help | 00000660 77 68 65 6e 20 72 65 71 75 69 72 65 64 2e 0a 54 |when required..T| 00000670 68 65 72 65 20 61 72 65 20 74 77 6f 20 6d 61 69 |here are two mai| 00000680 6e 20 6d 65 6e 75 73 2c 20 6f 6e 65 20 6f 66 20 |n menus, one of | 00000690 77 68 69 63 68 20 69 73 20 70 72 65 73 65 6e 74 |which is present| 000006a0 65 64 20 77 68 65 6e 20 74 68 65 20 75 73 65 72 |ed when the user| 000006b0 20 63 6c 69 63 6b 73 0a 6f 6e 20 74 68 65 20 73 | clicks.on the s| 000006c0 74 61 72 67 61 7a 65 72 20 69 63 6f 6e 2c 20 61 |targazer icon, a| 000006d0 6e 64 20 6f 6e 65 20 77 68 69 63 68 20 69 73 20 |nd one which is | 000006e0 61 76 61 69 6c 61 62 6c 65 20 77 68 65 6e 20 74 |available when t| 000006f0 68 65 20 22 76 69 65 77 22 20 77 69 6e 64 6f 77 |he "view" window| 00000700 0a 69 73 20 6f 70 65 6e 65 64 2e 20 20 54 68 65 |.is opened. The| 00000710 73 65 20 61 72 65 20 62 72 69 65 66 6c 79 20 64 |se are briefly d| 00000720 65 73 63 72 69 62 65 64 20 62 65 6c 6f 77 2e 0a |escribed below..| 00000730 0a 49 63 6f 6e 20 6d 65 6e 75 0a 0a 54 68 65 20 |.Icon menu..The | 00000740 69 63 6f 6e 20 6d 65 6e 75 20 70 72 6f 76 69 64 |icon menu provid| 00000750 65 73 20 61 6e 20 69 6e 66 6f 20 62 6f 78 20 61 |es an info box a| 00000760 6e 64 20 66 6f 75 72 20 6d 65 6e 75 20 6f 70 74 |nd four menu opt| 00000770 69 6f 6e 73 2e 0a 0a 4e 65 77 20 70 6c 61 63 65 |ions...New place| 00000780 20 61 6c 6c 6f 77 73 20 74 68 65 20 75 73 65 72 | allows the user| 00000790 20 74 6f 20 73 70 65 63 69 66 79 20 74 68 65 20 | to specify the | 000007a0 6f 62 73 65 72 76 65 72 73 20 6c 6f 6e 67 69 74 |observers longit| 000007b0 75 64 65 20 61 6e 64 20 6c 61 74 69 74 75 64 65 |ude and latitude| 000007c0 2e 0a 49 74 20 69 73 20 69 6e 69 74 69 61 6c 69 |..It is initiali| 000007d0 73 65 64 20 74 6f 20 6c 6f 6e 67 69 74 75 64 65 |sed to longitude| 000007e0 20 30 64 30 6d 45 20 61 6e 64 20 6c 61 74 69 74 | 0d0mE and latit| 000007f0 75 64 65 20 35 32 64 30 6d 4e 20 77 68 69 63 68 |ude 52d0mN which| 00000800 20 69 73 20 63 65 6e 74 72 65 64 0a 61 72 6f 75 | is centred.arou| 00000810 6e 64 20 43 61 6d 62 72 69 64 67 65 20 28 77 68 |nd Cambridge (wh| 00000820 65 72 65 20 65 6c 73 65 29 20 62 75 74 20 73 68 |ere else) but sh| 00000830 6f 75 6c 64 20 73 75 69 74 20 74 68 65 20 73 6f |ould suit the so| 00000840 75 74 68 20 6f 66 20 45 6e 67 6c 61 6e 64 2e 20 |uth of England. | 00000850 54 6f 20 73 65 65 0a 74 68 65 20 73 74 61 72 73 |To see.the stars| 00000860 20 74 68 61 74 20 61 72 65 20 6f 6e 6c 79 20 76 | that are only v| 00000870 69 73 69 62 6c 65 20 66 72 6f 6d 20 74 68 65 20 |isible from the | 00000880 73 6f 75 74 68 65 72 6e 20 68 65 6d 69 73 70 68 |southern hemisph| 00000890 65 72 65 20 79 6f 75 20 63 6f 75 6c 64 20 74 72 |ere you could tr| 000008a0 79 0a 35 32 64 30 6d 53 21 2e 20 20 54 68 65 20 |y.52d0mS!. The | 000008b0 22 64 22 20 61 6e 64 20 22 6d 22 20 61 72 65 20 |"d" and "m" are | 000008c0 73 68 6f 72 74 20 66 6f 72 20 64 65 67 72 65 65 |short for degree| 000008d0 73 20 61 6e 64 20 6d 69 6e 75 74 65 73 20 28 69 |s and minutes (i| 000008e0 6e 20 6c 6f 77 65 72 20 63 61 73 65 29 0a 61 6e |n lower case).an| 000008f0 64 20 74 68 65 20 22 4e 22 2c 22 53 22 20 28 66 |d the "N","S" (f| 00000900 6f 72 20 6c 61 74 69 74 75 64 65 29 20 6f 72 20 |or latitude) or | 00000910 22 45 22 2c 22 57 22 20 28 69 6e 20 75 70 70 65 |"E","W" (in uppe| 00000920 72 2d 63 61 73 65 29 20 73 70 65 63 69 66 79 20 |r-case) specify | 00000930 70 6f 73 69 74 69 76 65 0a 6f 72 20 6e 65 67 61 |positive.or nega| 00000940 74 69 76 65 20 64 69 72 65 63 74 69 6f 6e 73 2e |tive directions.| 00000950 0a 0a 4e 65 77 20 74 69 6d 65 20 66 6f 72 63 65 |..New time force| 00000960 73 20 61 20 72 65 63 61 6c 63 75 6c 61 74 69 6f |s a recalculatio| 00000970 6e 20 6f 66 20 61 6c 6c 20 6f 62 6a 65 63 74 20 |n of all object | 00000980 70 6f 73 69 74 69 6f 6e 73 20 74 61 6b 69 6e 67 |positions taking| 00000990 20 74 68 65 20 70 72 65 73 65 6e 74 0a 63 6c 6f | the present.clo| 000009a0 63 6b 20 73 65 74 74 69 6e 67 2e 0a 0a 53 68 6f |ck setting...Sho| 000009b0 77 20 53 6b 79 20 64 75 70 6c 69 63 61 74 65 73 |w Sky duplicates| 000009c0 20 74 68 65 20 6c 65 66 74 20 62 75 74 74 6f 6e | the left button| 000009d0 20 63 6c 69 63 6b 20 6f 6e 20 74 68 65 20 69 63 | click on the ic| 000009e0 6f 6e 2c 20 61 6e 64 20 6f 70 65 6e 73 20 74 68 |on, and opens th| 000009f0 65 20 76 69 65 77 0a 77 69 6e 64 6f 77 2e 0a 0a |e view.window...| 00000a00 51 75 69 74 20 69 73 20 73 65 6c 66 20 65 78 70 |Quit is self exp| 00000a10 6c 61 6e 61 74 6f 72 79 0a 0a 56 69 65 77 20 77 |lanatory..View w| 00000a20 69 6e 64 6f 77 20 6d 65 6e 75 0a 0a 54 68 65 20 |indow menu..The | 00000a30 76 69 65 77 20 77 69 6e 64 6f 77 20 6d 65 6e 75 |view window menu| 00000a40 20 70 72 6f 76 69 64 65 73 20 65 78 74 72 61 20 | provides extra | 00000a50 76 69 65 77 20 72 65 6c 61 74 65 64 20 66 61 63 |view related fac| 00000a60 69 6c 69 74 69 65 73 0a 0a 46 69 6e 64 20 6f 62 |ilities..Find ob| 00000a70 6a 65 63 74 20 61 74 74 65 6d 70 74 73 20 74 6f |ject attempts to| 00000a80 20 63 65 6e 74 72 65 20 74 68 65 20 76 69 65 77 | centre the view| 00000a90 20 61 72 6f 75 6e 64 20 74 68 65 20 63 68 6f 73 | around the chos| 00000aa0 65 6e 20 6f 62 6a 65 63 74 2e 0a 53 75 62 2d 6d |en object..Sub-m| 00000ab0 65 6e 75 73 20 61 72 65 20 75 73 65 64 20 74 6f |enus are used to| 00000ac0 20 63 68 6f 6f 73 65 20 74 68 65 20 74 79 70 65 | choose the type| 00000ad0 20 6f 66 20 6f 62 6a 65 63 74 2c 20 61 6e 64 20 | of object, and | 00000ae0 74 68 65 6e 20 73 70 65 63 69 66 79 20 61 0a 70 |then specify a.p| 00000af0 61 72 74 69 63 75 6c 61 72 20 6f 63 63 75 72 72 |articular occurr| 00000b00 65 6e 63 65 2e 20 4e 6f 74 65 20 74 68 61 74 20 |ence. Note that | 00000b10 73 74 61 72 20 6e 61 6d 65 73 20 6d 75 73 74 20 |star names must | 00000b20 6d 61 74 63 68 20 74 68 65 20 6e 61 6d 65 73 20 |match the names | 00000b30 61 66 74 65 72 0a 74 68 65 20 65 71 75 61 6c 73 |after.the equals| 00000b40 20 73 69 67 6e 73 20 69 6e 20 74 68 65 20 64 61 | signs in the da| 00000b50 74 61 62 61 73 65 2c 20 69 6e 63 6c 75 64 69 6e |tabase, includin| 00000b60 67 20 74 68 65 20 63 61 73 65 3b 20 74 68 65 73 |g the case; thes| 00000b70 65 20 67 65 6e 65 72 61 6c 6c 79 0a 73 74 61 72 |e generally.star| 00000b80 74 20 77 69 74 68 20 61 6e 20 75 70 70 65 72 20 |t with an upper | 00000b90 63 61 73 65 20 6c 65 74 74 65 72 2e 20 54 68 65 |case letter. The| 00000ba0 20 63 6f 6e 73 74 65 6c 6c 61 74 69 6f 6e 20 66 | constellation f| 00000bb0 69 6e 64 65 72 20 77 69 6c 6c 20 66 69 6e 64 20 |inder will find | 00000bc0 74 68 65 0a 66 69 72 73 74 20 73 74 61 72 20 69 |the.first star i| 00000bd0 6e 20 74 68 65 20 63 6f 6e 73 74 65 6c 6c 61 74 |n the constellat| 00000be0 69 6f 6e 2c 20 67 65 6e 65 72 61 6c 6c 79 20 41 |ion, generally A| 00000bf0 6c 70 68 61 2e 0a 0a 53 68 6f 77 20 63 6f 6e 73 |lpha...Show cons| 00000c00 74 73 20 77 69 6c 6c 20 74 6f 67 67 6c 65 20 74 |ts will toggle t| 00000c10 68 65 20 63 6f 6e 73 74 65 6c 6c 61 74 69 6f 6e |he constellation| 00000c20 20 69 64 65 6e 74 69 66 69 63 61 74 69 6f 6e 20 | identification | 00000c30 6f 70 74 69 6f 6e 20 6f 6e 20 6f 72 20 6f 66 66 |option on or off| 00000c40 2e 0a 0a 5a 6f 6f 6d 20 69 6e 20 61 6e 64 20 7a |...Zoom in and z| 00000c50 6f 6f 6d 20 6f 75 74 20 61 6c 6c 6f 77 20 74 68 |oom out allow th| 00000c60 65 20 75 73 65 72 20 74 6f 20 75 73 65 72 20 74 |e user to user t| 00000c70 6f 20 6f 70 74 69 6d 69 73 65 20 74 68 65 20 76 |o optimise the v| 00000c80 69 65 77 20 66 6f 72 0a 64 65 74 61 69 6c 2e 20 |iew for.detail. | 00000c90 46 61 69 6e 74 65 72 20 73 74 61 72 73 20 74 65 |Fainter stars te| 00000ca0 6e 64 20 74 6f 20 64 69 73 61 70 70 65 61 72 20 |nd to disappear | 00000cb0 61 73 20 79 6f 75 20 7a 6f 6f 6d 20 6f 75 74 20 |as you zoom out | 00000cc0 28 61 6e 64 20 62 72 69 67 68 74 65 72 0a 73 74 |(and brighter.st| 00000cd0 61 72 73 20 67 65 74 20 64 69 6d 6d 65 72 29 2c |ars get dimmer),| 00000ce0 20 74 6f 20 70 72 65 76 65 6e 74 20 74 68 65 20 | to prevent the | 00000cf0 76 69 65 77 20 66 72 6f 6d 20 62 65 63 6f 6d 69 |view from becomi| 00000d00 6e 67 20 63 6f 6e 66 75 73 65 64 2e 0a 0a 53 69 |ng confused...Si| 00000d10 6d 75 6c 61 74 65 20 61 6c 6c 6f 77 73 20 79 6f |mulate allows yo| 00000d20 75 20 74 6f 20 73 74 65 70 20 74 68 72 6f 75 67 |u to step throug| 00000d30 68 20 61 20 73 69 6d 75 6c 61 74 65 64 20 73 65 |h a simulated se| 00000d40 71 75 65 6e 63 65 20 6f 66 20 73 74 61 72 0a 70 |quence of star.p| 00000d50 6f 73 69 74 69 6f 6e 73 2c 20 72 61 74 68 65 72 |ositions, rather| 00000d60 20 6c 69 6b 65 20 61 20 66 61 73 74 20 66 6f 72 | like a fast for| 00000d70 77 61 72 64 20 62 75 74 74 6f 6e 2e 20 20 54 68 |ward button. Th| 00000d80 69 73 20 69 73 20 76 65 72 79 20 70 72 6f 63 65 |is is very proce| 00000d90 73 73 6f 72 0a 69 6e 74 65 6e 73 69 76 65 2c 20 |ssor.intensive, | 00000da0 73 6f 20 64 75 72 61 74 69 6f 6e 20 61 6e 64 20 |so duration and | 00000db0 73 74 65 70 20 73 69 7a 65 73 20 63 61 6e 20 62 |step sizes can b| 00000dc0 65 20 76 61 72 69 65 64 2e 20 20 49 74 20 70 72 |e varied. It pr| 00000dd0 6f 76 69 64 65 73 20 61 6e 0a 69 6e 73 69 67 68 |ovides an.insigh| 00000de0 74 20 69 6e 74 6f 20 74 68 65 20 77 61 79 20 74 |t into the way t| 00000df0 68 65 20 70 6f 73 74 69 6f 6e 20 6f 66 20 74 68 |he postion of th| 00000e00 65 20 73 74 61 72 73 20 63 68 61 6e 67 65 20 64 |e stars change d| 00000e10 75 72 69 6e 67 20 74 68 65 20 65 76 65 6e 69 6e |uring the evenin| 00000e20 67 2e 0a 0a 41 6c 6c 20 74 68 65 20 75 73 75 61 |g...All the usua| 00000e30 6c 20 52 49 53 43 4f 53 20 77 69 6e 64 6f 77 20 |l RISCOS window | 00000e40 62 75 74 74 6f 6e 73 20 61 70 70 6c 79 20 74 6f |buttons apply to| 00000e50 20 74 68 65 20 76 69 65 77 20 77 69 6e 64 6f 77 | the view window| 00000e60 20 74 6f 20 61 6c 6c 6f 77 0a 72 65 73 69 7a 69 | to allow.resizi| 00000e70 6e 67 2c 20 73 63 72 6f 6c 6c 69 6e 67 2c 20 66 |ng, scrolling, f| 00000e80 72 6f 6e 74 20 61 6e 64 20 77 69 6e 64 6f 77 20 |ront and window | 00000e90 63 6c 6f 73 65 2e 20 20 54 68 65 20 64 69 73 70 |close. The disp| 00000ea0 6c 61 79 65 64 20 6f 62 6a 65 63 74 73 0a 61 72 |layed objects.ar| 00000eb0 65 20 61 72 63 68 69 6d 65 64 65 73 20 73 70 72 |e archimedes spr| 00000ec0 69 74 65 73 2e 20 20 54 68 65 20 70 6c 61 6e 65 |ites. The plane| 00000ed0 74 73 20 61 72 65 20 64 65 73 69 67 6e 65 64 20 |ts are designed | 00000ee0 74 6f 20 62 65 20 72 65 61 73 6f 6e 61 62 6c 79 |to be reasonably| 00000ef0 0a 72 65 63 6f 67 6e 69 73 61 62 6c 65 2c 20 62 |.recognisable, b| 00000f00 75 74 20 6e 6f 74 20 72 65 70 72 65 73 65 6e 74 |ut not represent| 00000f10 61 74 69 76 65 20 69 6e 20 74 65 72 6d 73 20 6f |ative in terms o| 00000f20 66 20 74 68 65 69 72 20 6d 61 67 6e 69 74 75 64 |f their magnitud| 00000f30 65 2e 0a 0a 54 68 65 20 70 72 6f 67 72 61 6d 20 |e...The program | 00000f40 69 73 20 77 72 69 74 74 65 6e 20 63 6f 6d 70 6c |is written compl| 00000f50 65 74 65 6c 79 20 69 6e 20 42 42 43 20 62 61 73 |etely in BBC bas| 00000f60 69 63 20 77 69 74 68 20 74 77 6f 20 6c 69 62 72 |ic with two libr| 00000f70 61 72 69 65 73 20 66 6f 72 0a 73 70 72 69 74 65 |aries for.sprite| 00000f80 20 61 6e 64 20 77 69 6e 64 6f 77 73 20 68 61 6e | and windows han| 00000f90 64 6c 69 6e 67 2e 20 20 20 54 68 65 73 65 20 63 |dling. These c| 00000fa0 6f 75 6c 64 20 62 65 20 65 78 74 72 61 63 74 65 |ould be extracte| 00000fb0 64 20 61 6e 64 20 75 73 65 64 20 77 69 74 68 0a |d and used with.| 00000fc0 6f 74 68 65 72 20 70 72 6f 67 72 61 6d 73 2e 20 |other programs. | 00000fd0 20 53 6f 6d 65 20 72 6f 75 74 69 6e 65 73 20 28 | Some routines (| 00000fe0 73 70 65 63 69 66 69 63 61 6c 6c 79 20 74 68 65 |specifically the| 00000ff0 20 72 65 64 72 61 77 69 6e 67 20 61 6e 64 20 64 | redrawing and d| 00001000 61 74 61 62 61 73 65 0a 69 6e 74 65 72 70 65 74 |atabase.interpet| 00001010 65 72 29 20 68 61 76 65 20 62 65 65 6e 20 6f 70 |er) have been op| 00001020 74 69 6d 69 73 65 64 20 74 6f 20 6d 61 6b 65 20 |timised to make | 00001030 74 68 65 20 70 72 6f 67 72 61 6d 20 6d 6f 72 65 |the program more| 00001040 20 75 73 61 62 6c 65 2c 20 61 6e 64 20 73 6f 0a | usable, and so.| 00001050 6d 61 79 20 62 65 20 6c 65 73 73 20 72 65 61 64 |may be less read| 00001060 61 62 6c 65 2c 20 62 75 74 20 74 68 65 20 6f 70 |able, but the op| 00001070 65 72 61 74 69 6f 6e 20 6f 66 20 74 68 65 20 70 |eration of the p| 00001080 72 6f 67 72 61 6d 20 63 61 6e 20 62 65 20 73 65 |rogram can be se| 00001090 65 6e 2e 0a 53 6f 72 72 79 20 61 62 6f 75 74 20 |en..Sorry about | 000010a0 74 68 65 20 22 6d 61 6a 69 63 20 6e 75 6d 62 65 |the "majic numbe| 000010b0 72 73 22 20 62 79 20 74 68 65 20 77 61 79 2e 20 |rs" by the way. | 000010c0 48 61 70 70 79 20 73 74 61 72 67 61 7a 69 6e 67 |Happy stargazing| 000010d0 21 0a 0a 54 68 65 20 70 72 6f 67 72 61 6d 20 68 |!..The program h| 000010e0 61 73 20 73 75 63 63 65 73 73 66 75 6c 6c 79 20 |as successfully | 000010f0 62 65 65 6e 20 63 6f 6d 70 69 6c 65 64 20 75 73 |been compiled us| 00001100 69 6e 67 20 74 68 65 20 53 69 6c 69 63 6f 6e 20 |ing the Silicon | 00001110 56 69 73 69 6f 6e 0a 52 69 73 63 42 61 73 69 63 |Vision.RiscBasic| 00001120 20 43 6f 6d 70 69 6c 65 72 2c 20 77 68 69 63 68 | Compiler, which| 00001130 20 73 70 65 65 64 73 20 75 70 20 64 72 61 77 69 | speeds up drawi| 00001140 6e 67 20 61 6c 6f 74 2c 20 62 75 74 20 75 6e 66 |ng alot, but unf| 00001150 6f 72 74 75 6e 61 74 65 6c 79 20 0a 69 6e 63 72 |ortunately .incr| 00001160 65 61 73 65 64 20 74 68 65 20 63 61 6c 63 75 6c |eased the calcul| 00001170 61 74 69 6f 6e 20 74 69 6d 65 2e 0a 0a 53 75 67 |ation time...Sug| 00001180 67 65 73 74 69 6f 6e 73 20 66 6f 72 20 65 6e 68 |gestions for enh| 00001190 61 6e 63 65 6d 65 6e 74 73 2f 62 75 67 20 66 69 |ancements/bug fi| 000011a0 78 65 73 20 65 74 63 20 74 6f 3a 20 20 0a 0a 53 |xes etc to: ..S| 000011b0 74 65 76 65 20 45 6c 6c 77 6f 6f 64 20 28 42 53 |teve Ellwood (BS| 000011c0 63 29 0a 43 61 73 74 6c 65 20 46 61 72 6d 0a 48 |c).Castle Farm.H| 000011d0 61 73 73 65 20 52 6f 61 64 0a 53 6f 68 61 6d 2c |asse Road.Soham,| 000011e0 20 4e 65 61 72 20 45 6c 79 0a 43 61 6d 62 72 69 | Near Ely.Cambri| 000011f0 64 67 65 73 68 69 72 65 0a 0a 50 2e 53 2e 20 54 |dgeshire..P.S. T| 00001200 68 61 6e 6b 73 20 74 6f 20 45 4f 20 43 6f 6d 70 |hanks to EO Comp| 00001210 75 74 65 72 20 4c 54 44 20 28 43 61 6d 62 72 69 |uter LTD (Cambri| 00001220 64 67 65 29 20 66 6f 72 20 74 68 65 20 75 73 65 |dge) for the use| 00001230 20 6f 66 20 74 68 65 0a 41 63 6f 72 6e 20 52 31 | of the.Acorn R1| 00001240 34 30 20 77 69 74 68 20 54 41 58 41 4e 20 6d 75 |40 with TAXAN mu| 00001250 6c 74 69 73 79 6e 63 20 6d 6f 6e 69 74 6f 72 2e |ltisync monitor.| 00001260 0a 0a 0a 0a 0a |.....| 00001265
.