Apple Mechanic; a programmer's program. (evaluation) Paul Bonner.
A Programmer's Program
My first thought in attempting to review Apple Mechanic is that Bert Kersey and Jack Cassidy (known professionally as the Beagle Brothers) are a pair of lunatics. In a single disk selling for less than $30 they include a disk utility program, an excellent shape table editor, and a pair of hi-res text generators. Then they throw in a half-dozed useful little utility programs, and a Tip Book and PEEKS and POKES chart filled with information worth almost any price to anyone interested in Applesoft programming. Finally, as if all that weren't crazy enough, everything on the disk is listable and unprotected. They even encourage you to modify your programs to incorporate the routines on the Apple Mechanic disk.
My next thought is that all these features make Apple Mechanic very difficult to review. It is even difficult to classify. Let's call it a utility disk for want of a better word, and examine its features one at a time, beginning with the routines devoted to the shape tables.
The program for creating shape tables is called Shape Editor. The tables it creates may contain up to twelve 48 X 63 point shapes. Once you have loaded the sample table included on the disk or a table that you have created, the entire table is displayed on the hi-res screen.
When you enter the command to edit a shape, the display changes so that you see the shape to be edited displayed twice--once in its actual size on the right side of the screen, and a second time enlarged three times in a plotting grid on the left side of the screen.
Plotting is done using the left and right arrows, the A and Z keys, and the spacebar. You can choose to have the shape you have selected pre-plotted or imprinted on the screen, either of which gives you a design to follow in changing the shape.
However, only the plotting you do while in the additing mode is entered into the final shape table. This can be rather tedious, because you must redraw the entire shape even if you want to make only a small change in it, but it does allow you to draw a shape without thinking about efficiency and then trace over an imprinted-image of the shape to draw it more efficiently.
A useful companion to Shape Editor is the Shape Analyzer utility. Once you have created a shape table, you can use the Shape Analyzer to experiment with DRAWing and XDRAWing any shape in the table on different color backgrounds.
You can also view the selected shape in any degree of rotation or in any scale, and move the shape up-and-down or across the screen. Shape Analyzer also lets you analyze shapes vector-by-vector, which is helpful when you want to find a way to draw a shape more efficiently.
The documentation for Shape Editor and Shape Analyzer, and indeed for every program on the disk, is excellent. You get clear and precise instructions on how to use the shape tables created with these programs, including instructions for rudimentary animation.
Most of the commands for the programs on the disk require only a single keystroke. A key chart that identifies the commands for each program is included in the Apple Mechanic package.
The authors have also included several "Hi-Res Manipulations,' which tell you how to draw on one hi-res page while viewing another and how to do instant switching between the two hi-res pages and instant color-fills of either page. The disk also includes a pair of text programs that automatically move the contents of one hi-res page to the other.
When you add up these programs, you don't have a complete graphics package. What you do have is an assortment of valuable tools waiting for you to put them to use. Using the Shape Editor to create shape tables is much easier than analyzing the shape vectors bit-by-bit and converting them to hexadecimal code. (Although, if you want to learn to enter shape tables that way, the Apple Mechanic manual includes three pages of information telling you how to do it.)
Unfortunately, you still have to have some artistic sense to create interesting shapes. In my case, that made the Shape Editor somewhat disappointing. Still, the first time I used it I was able to create the necessary shapes for a two-player tennis game I was writing. They weren't exactly the quality of the monsters in Ultima, but they were much better than anything I could have drawn otherwise.
The next group of routines on the Apple Mechanic disk is designed to create and display hi-res text. Included on the disk are six ready-to-use character fonts, each containing 95 characters. Two of these are small fonts containing characters with a maximum size of 7 X 8 points, and the others are large fonts containing characters of up to 14 X 16 points. All six fonts contain a complete set of both upper- and lowercase characters. No special hardware is required to use the lowercase characters.
The fonts used by Apple Mechanic are shape fonts, meaning that they are designed and used like shape tables. The characters can be drawn in any color, and can be XDRAWn so that they contrast with the background color on the screen.
One disadvantage of shape fonts is that they take up more disk space than other fonts (about 18 sectors for large fonts compared to five sectors for some of the fonts found on Apple's DOS Tool Kit). The only other disadvantage of which I am aware is that neither the character fonts nor the shape tables created with Apple Mechanic are compatible with those used by most other programs.
The Font Editor program allows you to modify and of the fonts on the disk and to create entirely new fonts. The operation of this program is almost exactly like that of the Shape Editor. It is relatively easy and quite satisfying to create an entirely new character set with this program. In addition, it can be used to create shape tables containing more shapes than are allowed in tables created with the Shape Editor program.
The Apple Mechanic disk also contains a Font Splitter utility, a routine that allows you to eliminate unwanted characters from a font to save disk space.
Having created a character set, you need a way to use it. The Apple Mechanic disk contains two programs for that purpose. The first, called Xtyper lets you enter hi-res text directly onto page one of the hi-res screen. You can use up to three fonts at once and can load other fonts at any time.
Before beginning to enter text, you are given the option of clearing the hi-res screen or loading an existing hi-res picture to which you want to add text. You then begin entering text on the screen, using the ESCAPE key to toggle back and forth between upper- and lowercase.
Changing the color of the type and changing to another of the fonts in memory are both simple two-keypress functions. When you have finished, you can return to the main menu and save the hires page under any name that you like, thus enabling you to load and view it in other programs.
The second program for using the hires character sets is called Hi-Writer. By itself, Hi-Writer does nothing. It is meant to be used as a subroutine (consisting of lines 50-500) in your own programs.
Among the options available with Hi-Writer are mixed upper- and lowercase, a choice of any background color, automatic centering of lines, and inverse text. You can also rotate text 90, 180, or 270 degrees, allowing you to print lines up-side-down or sideways. There is no provision in Hi-Writer for non-destructive animation using the second hi-res page, but since the program is listable it probably would not be difficult to modify it to include that feature.
It is unfair to compare Xtyper and Hi-Writer, since they serve different purposes. Xtyper is very good for labeling static hi-res images, while Hi-Writer creates dynamic images. But I think Hi-Writer is the more useful of the two. It doesn't take up much memory and adds only 10 disk sectors to the length of a program, while Xtyper requires 34 sectors for each hi-res page it saves.
Also, since Hi-Writer acts as a subroutine, the rest of your program can do anything you desire. Thus, it is possible to have purple hi-res cows created with Shape Editor zooming around the screen while Hi-Writer generates text describing each cow's milk production.
The last major program included on the disk is Byte Zap. It has little or nothing to do with the other programs on the disk, but it can prove quite useful in its own right, especially if you have ever screamed "Oh no!' after hitting RETURN and seeing the disk drive light come on.
Byte Zap allows you to examine and change the contents of a disk sector-by-sector. Thus, it is possible to restore an accidentally deleted file or repair a blown Volume Table of Contents.
Byte Zap displays the contents of each location in the sector being examined in any one of five formats: hexadecimal, decimal, ASCII, ASCII with flashing characters changed to inverse, or catalog--a special mixed hex and ASCII format used for viewing the catalog sectors. You can switch back-and-forth between formats instantly.
Depending on how well you understand Apple DOS, using Byte Zap can have entertaining, life-saving, or disastrous effects. The entertainment value lies in changing Apple DOS commands and error messages, or in changing a Level-2 thief on your Wizardry disk to a Level-96 ninja.
The lifesaving value comes from the ability to restore an accidentally deleted file or to recover files from a disk with a bad DOS or a blown sector.
The disastrous effects of Byte Zap are, unfortunately, inherent in any program that changes the contents of a disk sector. It is quite possible to make a fatal error that will render a file unreadable. If you are changing the DOS, you can even blow the entire disk. The risks increase further if you try to alter a sector on a copy-protected disk. Fourtunately, the authors of Byte Zap have included numerous warnings to back-up your disks, and the program always asks if you are sure you know what you are doing before it actually writes anything to disk.
That about covers the major programs on the Apple Mechanic disk. I should make some mention, though, of the Tip Book and the PEEKS and POKEs Chart. The Tip Book, which makes up the first 19 pages of the manual, is filled with listings of short subroutines and observations about quirks in Applesoft or the monitor. Some of these--like the program to convert Arabic numbers to Roman numbers--have rather limited value. Others, however--like a print-using subroutine and an ONERR subroutine which lists the line in which an error occurred and points to the offending statement in multiple-statement lines--are worth their weight in gold.
The PEEKS and POKEs Chart is an incredibly useful list of monitor subroutines and the memory locations of all kinds of wonderful data. Having been weaned on Applesoft, it gives me great joy to fill my programs with lines that CALL this and POKE that. The monitor subroutines listed on the PEEKs and POKES Chart have much faster execution times than their corresponding Applesoft commands.
I grow more enthusiastic about Apple Mechanic each time I work with it. However, the very thing that I like about the disk keeps me from recommending it without reservation. That is, that none of the programs on Apple Mechanic is designed for users who want to boot a disk and then sit back and let it do all the work. They are written for programmers who want a product that they can expand upon, modify, and incorporate into their own programs. For that use, the programs on Apple Mechanic are excellently written and documented.
Thus, I recommend Apple Mechanic to programmers and tinkerers who are interested in graphics, hi-res text, or disk storage, and who want programs that serve as both tools and teachers in those areas.
Photo: This hi-res picture incorporates some very simple shapes created with Shape Editor and hi-res text generated with Xtyper.
Products: Beagle Bros Micro Software Apple Mechanic (computer program)