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1983-05-04
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ShapeShifter 3.1
Review by Marc Hoffman
Within the past year, we Amiga users have seen much turmoil, despair, hopefulness,
and anticipation, all feelings associated with our favorite computer's future. Knowing
that it is a fact that some Amiga software companies are beginning to produce more on
the Mac and PC side of the fence, leaving us in the lurch -- Play, Inc.'s Brilliance, for
example -- many once die-hard Amiga users are now being forced to look at these very
same alternate platforms in order to keep pace. But now there is a way to run
Macintosh software on the Amiga without any hardware attachment to mess with.
Enter the ShapeShifter, a shareware Mac emulator for the Amiga.
The ShapeShifter is a program available from BBSs, user groups, etc., and is
freely-distributable in a demo version; this demo is very usable and functional. The
main features taken out of the demo version are the abilities to make a dedicated Mac
partition on a hard drive and to use SCSI devices such as CD ROMs and various
removable media. The registration fee for the real version is $40. This $40 buys the
user a "key file" which unlocks the disabled features of ShapeShifter. What's more, this
special file will work with future versions of ShapeShifter.
The package contents include: the main program, PrepareEmul (frees lower 8K of
chip RAM), a well-done AmigaGuide based on-line manual, KickShifter (for softkicked
Amigas), a Mac Handler designed to provide Amiga OS and application access to the
Mac drives, and SaveROM, a program designed to pull the information off real Mac
ROMs and save it as a disk file for use with ShapeShifter. Two pieces of software not
included are the Mac ROMs and Mac OS software. It must be stated that Christian
Bauer, programmer of ShapeShifter, does not support piracy of the real Mac ROMs. In
fact, Mr. Bauer will not accept an order for ShapeShifter unless the buyer signs a
contract stating that this is understood. ROMs must be either purchased from an
authorized salesperson or copied from a real Macintosh computer.
ShapeShifter doesn't use the outdated 256K ROMs as in some other emulators,
which can be rather difficult to find. Depending on the hardware level of the Amiga in
question, the ROMs will have to be either the 512K or 1MB flavors. The difference is
that the 512K ROM is not entirely 68040 compliant, and the 1MB is. If a 512K ROM is
used with a 68040, for example, then the processor's caches will need to be turned off,
decreasing performance. The difference is in the speed and performance of the
emulation. PowerMAC ROMs will not work with ShapeShifter.
Upon installing PrepareEmul and cold-booting the Amiga, the emulation is ready to
go. Running ShapeShifter brings up the main requester greeting the user with the
items: graphics, volumes/disks, floppies, SCSI, Memory, Serial, Network, and MISC.
(for direct/indirect mouse polling, ROM write protection, and FPU usage).
Under the Graphics panel (Figure1), several selections are available: Color Depth,
Screen Type, which contains drivers for standard Amiga displays, CyberGraphics,
Merlin graphics cards, EGS graphics cards, Picasso graphics cards, a driver for running
a monochrome Mac in a window right on the Amiga Workbench (Figure2), and a
selection for an external graphics driver. Also included are gadgets for Screen
Mode/Size, a Refresh Rate entry box, a black border option for AGA Mac screens, a
Refresh Always option, use of the 68040's MMU to refresh the screen changes, and a
nifty little option that allows the use of the Amiga's sprite pointer on the Mac screens.
The Macintosh's built-in graphics handling routines, 32-bit Quickdraw, is quite
different than the Amiga's. On the Amiga, most applications expect the display to be in
what is known as a "planar" format, meaning that the screen is composed of layered
bitplanes. As the number of layers or bitplanes increases, so does the number of
colors. The Mac does not work in quite the same manner. Instead of using bitplanes, it
uses "chunky pixels." In a nutshell, a chunky pixel contains all color information no
matter how many colors are displayed on the screen. For example, a 32-bit chunky
pixel screen mode could display a 2-color screen, 32-color screen, or even a full 16.7
million color screen. Since the Mac and Amiga are so different in these respects, a
problem exists in trying to get the Amiga to emulate a true chunky screen. Enter the
refresh setting, which periodically converts the Mac's chunky pixel format to the Amiga's
planar screen format. This setting defines a period taken between each refresh. But be
warned: the results are very slow. Just moving the mouse pointer around the screen
can be a tedious task. However, if an MMU equipped 68040 is used and the Mac ROM
is set to "Write Protect" under the MISC section, then the MMU is forced to refresh only
those parts of the screen that change. Performance is still somewhat sluggish, but it is
a world above the former method of refreshing the screen. And with the use of the
Amiga's sprite mouse pointer, the MMU doesn't need to update the pointer, thereby
increasing the speed even further.
Probably the best way to overcome this problem is to use a graphics card with
built-in chunky pixels. Performance on my Spectrum (GVP) card in 256 colors is just as
fast as a real Mac, hands down. Unfortunately, my Spectrum card's chunky pixel ability
is limited to only 256 colors. When using 15 and 24-bit screen depths, the MMU must
refresh the screen as with the Amiga Bitplanes mode. Using the new CyberVision 64
card gives the emulation quite a speed boost comparable with a real Mac, even at 15
and 24-bit color modes.
ShapeShifter supports many forms of mass storage and retrieval including floppies,
hard disks, CD ROMs, and removable media. In the volumes/disks menu, the user can
create two types of hard disk volumes for use with the emulation: FileDisk and
DeviceDisk. A FileDisk is a "fake" hard drive. This option creates a custom-sized file
on an AmigaDOS volume that is seen by the Emulation to be a stand-alone Macintosh
hard drive. The drawback to this approach is speed. Remember that this is not a real
Mac hard drive, and so the Amiga must "jump through some hoops" in order to get it to
work. On the upside, with a FAST SCSI 2 interface and drive, the speed factor is very
tolerable for 10MB to 65MB partitions. Probably the biggest advantage of FileDisks is
the ability to create multiple Mac volumes at will (only two FileDisks can be used at a
time, however), and not have to re-partition the AmigaDOS device.
The second option is to make a dedicated Macintosh partition on the Amiga hard
drive or else to dedicate an entire hard drive to the Mac emulation; both are referred to
by ShapeShifter as a DeviceDisk. This approach increases hard disk speed factors by
several times over. As with the FileDisk, two DeviceDisks can be used at one time.
Amiga floppy drives can also be used with the Macintosh emulation. If a high
density drive is used, the Amiga can read/write Mac high density disks. Low density
disk support is provided via a special 720K format that is readable not only on the
ShapeShifter, but is also readable on a real Macintosh. Unfortunately, there is no way
to read/write Mac 800K low density disks within the Amiga drives. To do this, a real
Macintosh or compatible drive is needed. Emplant and A-Max Mac disks are also
supported.
ShapeShifter is bundled with a Mac Handler that allows AmigaDOS access to
volumes on the Mac side. This is particularly useful, for not even CrossMac is able to
decipher the FileDisks; AmigaDOS sees FileDisks as files only, and cannot access the
information contained within them. With the Mac Handler program, the FileDisk or
DeviceDisk is deposited right on the Workbench as a normal AmigaDOS device, and is
therefore accessible to Amiga applications. Unfortunately, only one Mac device is
available at one time, and the user must specify which device will be accessed via the
Tooltypes in the Workbench Information Requester.
In order for the emulation to work, a specific amount of memory must be allocated
to ShapeShifter to use as the maximum amount available for the Mac. According to the
documentation, this amount of RAM must be in one, contiguous block. Fragmentation
of the memory on the Amiga side will cause problems here; two solutions to solve
fragmented memory are to reset the Amiga or to use the command "avail flush" in the
AmigaShell. It is interesting to note that this deficiency in memory handling is not the
fault of the Amiga or ShapeShifter. It is due to restrictions of the Mac OS. It would be
interesting to see if the programmer of ShapeShifter could find a way around this
problem. ShapeShifter can also be set to use the largest free block of memory,
ensuring that the maximum amount of memory can go to the emulation. The Amiga and
Mac emulation can also share information in memory via their clipboards. Text written
to the Mac clipboard will show up in the Amiga's clipboard, and vice versa, with an
automatic conversion of text taking place.
ShapeShifter is also very flexible with its support of serial/parallel ports. It has the
ability to use the Amiga's serial and parallel ports as the Mac's printer and modem ports,
and it also supports I/O expansion cards. I have tested this ability using Hewlett
Packard's HP PaintJet printer driver for the Macintosh, and it prints out graphics and
text with excellent speed.
As for networking, ShapeShifter supports Ethernet cards using a SANA-II driver for
use with AppleTalk or MacTCP. The documentation discourages the use of System
7.0.1 if ShapeShifter is to be used with networking.
Mouse Polling, Write-Protect ROM, and Do Not Use FPU all compose the MISC
menu. Mouse polling can be either directly controlled by ShapeShifter, which
increases compatibility with Mac software, or it can be polled by the Amiga OS, which
allows the use of input devices like graphics tablets or touchscreens.
As explained earlier, write-protecting the Mac ROM enables the MMU to refresh the
screen. It also prevents some buggy programs from trashing the ROM. This feature
only works on a 68040.
Enabling the option Do Not Use FPU prevents the Mac from accessing the floating
point unit on the main processor.
I tried the ShapeShifter with many different Mac programs, both public domain and
commercial, and here is a run down of the results. In the shareware/PD category, I
tested the programs of JPEGView, GIFConverter, Giffer, the Sound Treker, and
MacLHA. All three programs seemed to function well, except for a couple of
exceptions.
Giffer: Under its "About Giffer" portion of the Apple Menu, the program will display
small, random animated sequences. While in 256 colors, these animations play
flawlessly. But in the higher color modes, one of the animations causes the error "The
application 'unknown' has unexpectedly quit because an error of type 4 has occurred."
This is a minor point, but is still worth mentioning.
Under the commercial arena of software, I tested the following titles: Fractal
Design Painter 3.0 (Figure 3), MicroSoft Works, and QuickTime, all of which worked
very well. The personnel at Computer Hardware, the Mac dealer that was gracious
enough to let me test the ShapeShifter with commercial Mac software, were very
impressed with the performance of the emulation; they even said that it "looks like a real
Mac."
Yes, even with the best of programs, there are always some problems that crop up
here and there. First of all, when testing the emulation under 24-bit, 16.7 million color
mode under the CyberGraphics driver with my GVP Spectrum card, the graphics
exhibited distortion, making the emulation unusable in many cases. But when I used
the updated CyberGraphics drivers written especially for the CyberVision 64 graphics
card, the distortion ceased. So this was probably a problem with the older
CyberGraphics libraries, or possibly with the CyberGraphics implementation on the
Spectrum card. I also tried booting the emulation using the older EGS graphics libraries
for the Spectrum card. Although the ShapeShifter booted, I was unable to run certain
software, most notably Painter 3.0. One other technical problem deals with the graphics
handling of the emulation. At certain times on the Mac side when a program is run that
requires constant updating of parts of the screen (e.g., the alarm clock, with its changing
numbers), these screen changes will appear on the Amiga Workbench. Seeing the Mac
alarm clock showing through the Amiga Workbench can be rather disquieting. Also,
although ShapeShifter does preemptively multitask, the program still has some
problems, and sometimes the program will lock the entire Amiga up.
According to the documentation, the following programs will not work with the
ShapeShifter: Peace of Mind and Snooper (hardware diagnostic programs), SoundEdit
16, Apeiron, Emagic MicroLOGIC, WACOM ArtPad driver, Epson Stylus driver, and
strangely enough, the System 7.0.1 Sound Control Panel. But Mr. Bauer is always
continuing to upgrade and improve the product, and it may be possible that a new
version of ShapeShifter will be available by the time this review hits the presses.
In conclusion, what I saw of this software impressed me greatly. This review can
be ended by asking one question: Why is ShapeShifter shareware? This program is
definitely commercial in quality. Mister Christian Bauer should take a bow. Where else
can a $40 Mac of this quality be purchased? The new owners of the Amiga technology
should seriously think of licensing this software and adding it to the next release of the
Amiga's OS. It would be like buying two computers in one!
I would like to thank the following for their helping me in the review of this product:
Mr. Dave Babbitt, Mr. Marc Regenos, and the rest of the staff of Computer Hardware,
Inc., of Kearney, NE.