MasterClass John Kennedy is still concerned with getting smaller and smaller, as well as smarter and smarter. More Compression Last month we touched on data compression and what a useful method it was of saving disk space (and downloading time as well if you use a modem a lot). The standard Amiga archiver has always been LHA, which you can see for yourself if when you log into a BBS and see all the files ending with the .lha suffix. You'll find the LHA program itself lurking on magazine coverdisks or on your local BBS, and you sould add it to your collection of Amiga utilities as soon as possible. Recently a new archiver called LZX has been popping up a lot in FidoNet conversations. LZX promises to run faster and work better than LHA, so of course it deserves some attention. You can download LZX from the usual on-line places (such as the Aminet, which is where I got it) and Bulletin Boards such as Creations (modem number: 0181 6659887). It is used in exactly the same was as LHA, that is, from the Shell with commands like: lzx a my_archive #?.iff Which will bundle up all the files in the current directory ending in .iff and store them in a new file called my_archive.lzx. In order to check out the claims for LZX, I performed the following tests. First of all I archived ten large IFF image files (which usually don't pack up well as they are already encoded slightly) and secondly I archived a pile of text files. Graphics Files Text Files Original Size 6284520 2284752 LHA Size 5063205 805418 LHA Time 2m 03s 0m 44s LZX Size 5018060 710674 LZX Time 1m 59s 0m 46s LHA version 1.38, LZX version 1.00 As you can see, in both cases the LZX compression was slightly better -- especially with text files. The time difference however was minimal (and slightly worse for the text files). Whether or not a change over to the LZX system is merrited remains to be seen. An update to version 1.01 is expected "real soon now", and this will be worth checking out. In any case, if you find that you need to pack up a lot of data it will be worth your while to see if LZX makes any difference. Interestingly, both these coding system rely on the LZW (Lez Zemple Welch) compression system, which was at the heard of the recent "CompuServe to charge for GIFs" stories you may have read in the computer press. The GIF graphic file standard belongs to CompuServe and it use LZW, which was developed by Unisys. LZW belongs to Unisys and want to get some money from it -- hence the proposed GIF-tax. It will be fun to see Unisys try to get money for all the programs which are compressed with Lhz or Lzx. Workbench Icon Replacements Have a look at the nice Workbench pictures shown below. Look a bit different from yours? Well, unless you have NewIcons installed on your Amiga, it should. Like Magic Workbench, NewIcons is a set of replace icons to smarten up your Workbench display. Also like MagicWb, it's available from the Aminet Internet site and many BBS and Public Domain libraries. Many folk are worried about using new icons, especially as some users have reported unexplained crashes. First of all, the original programs like MagicWB contained icons which were only that -- icons. When you look at any files stored on your disks, you'll see files ending in .info. These files are the files which contain the information the Amiga uses to display the little graphic. They are not programs in their own right, and in fact are stored separately from the programs they are associated with. The Workbench clock program for example, is actually two individual files: the program itself, and the .info icon file. Without the .info file, there would be no icon display but the program could still be used (either from the Shell or by using the "Display All Files.." option from the Workbench menu). Thus there is no way that the new icons themselves could interfere with the program. If things do go wrong when experimenting with icons, there are a few things that should be checked: 1. Icon type Icons are classed into different types, in order to inform the Amiga's operting system if it is working with drawers, disks or programs. If you copy an icon from a program file and make it into a drawer you may forget to alter the type with odd results. You can check the type by loading the icon into the Icon Editor program supplied on the Workbench Extras disk. Remember that if using the Workbench 3.0 Icon Editor that it sometimes goes bonkers and saves a large outline around your images. If this happens, your only recourse is to use the Workbench 2 editor, or a third party program such as Iconian (available from the usual public domain / shareware outlets). 2. Tools The .info file stores the graphical data, but it also has a secondary purpose: storing tool types. If you examine an .info file using the Information option from the workbench (highlight the icon and press Right-Amiga-I) you might see a list of tool types associated with the icon. This method is used to customise programs: for example, you might want the program to use certain screen colours or certain keyboard shortcuts. If the program has been written to look at the tool types then these can be changed to reflect your own purposes. The stack size is sometimes set from within the .info file as well -- the stack is the amount of memory which a program is allocated. The programs can arise if you simply replace one icon with another: you might overwrite the .info data and loose all these settings. If you are changing icons, remember to look at the tool and stack settings first. The install program with MagicWB and NewIcons will try and retain all these settings and therefore there shouldn't be any problems. 3. Disk and memory usage All the new icons are considerably more detailed than the standard icons and therefore use up more space. For the best visual effect you may to run your Workbench with more colours than you are used to (8 or 16). This will use up more chip memory than normal which can lead to problems on unexpanded systems. If you are running totally from floppy, you'll have to think carefully about using an icon replacement scheme as it will slow things down ever so slightly and use more memory. NewIcons works slightly different in that it virtually re-writes the way the icon system works. It adds some programs to your startup sequence and re-writes the system to display the new images. It sounds a bit extreme, but it has the advantage of fixing the short-comings with the Workbench palette system. Have a look at the example pictures and if you decide you like what you see, either get the file from the Aminet or local BBS or PD library. The newer versions of MagicWB also includes some "active" parts, specifically some programs to make sure the palette is organised sensibly. As you can see from the images, the end result is very snazzy, although unless you can display a DblPAL or Multiscan image on your monitor you may find your screen starts to become a little too cluttered. I'm quite happy with set-up, which is a collection of bits and pieces I've collected over the years. And by the way, the line of icons which appears in several of the images is produced by the ToolsMaster program. This provides you with an easy way of leaving programs out on the Workbench: especially handy if you have a hard drive. As with all the programs mentioned here, keep a look out for it on-line or from your library. Something else you should watch out for is the WallPaper collection. There are hundreds of well drawn textures for you to tile as a backdrop pattern. They range from the usual mottled shades or grey to pictures of that girl from Twin Peaks who everyone apparently fancied a year or so ago. These patterns are widely available so try 'em out. None are quite so bad as "Sexybench" which includes several very poor manga-style cartoon drawings of the female form. Not the sort of thing you want on your Workbench when Lisa walks into the office... captions magicwb1 This is what your Workbench could look like if you installed Magic Workbench. Notice that all the drawers have been altered so that you can tell what is in them before you even open them: neat idea. magicwb2 Magic Workbench looks particularly well when used with a nice shaded backdrop pattern, like this. Notice the "toolbar" along the bottom of the screen, created with ToolManager. Each tool icon is an IFF brush, so you can create a system that looks exactly the way you want it to look. magicwb3 If you have an AGA Amiga (an A1200 or A4000) you can use the special MagicCopper routines to provide a smoothly shaded background. You have to wonder if perhaps things are going just a little too far... newicon1 This is the demo picture which comes with NewIcons. Instead of shading, the icons are a more OS/2 style coloured image. They may be a little on the large size if you don't have a flicker-free large screen mode. john My own workbench looks a little cluttered at the moment, thanks to the Wallpaper texture I'm trying out in the background. Think I'll loose the Giant's Causeway and go back to good old marble.