PearPC
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PearPC is an architecture-independent PowerPC platform emulator capable of running most PowerPC operating systems, such as Mac OS X, Darwin and Linux. It is released under the GPL. It can be executed on Microsoft Windows, Linux and other systems based on POSIX-X11. The first official release was made on May 10, 2004.
The emulator features a Just-in-time (JIT) processor emulation core which dynamically translates PPC code into x86 code, caching the results. Despite running only on x86 host architectures, the JIT emulation core runs at least ten times faster than the architecture-independent generic processor emulation core, and is the key to achieving usable real-time emulation.
PearPC is currently in development and is advancing quickly in speed, stability and features. It is hoped to achieve the goal of 1/10 host speed, ie. the speed of a 300 MHz PowerPC G3 on a 3 GHz Intel Pentium 4, relatively soon. Individuals are making builds with more features like native CD-ROM support and even progress emulating sound has begun. Popular PearPC sites that provide builds also include Altivec support for PowerPC G4 processors. The latest known breakthrough at the time of this writing is initial support for graphics cards acceleration, which in theory should provide a major performance boost due to OS X's hardware-accelerated GUI known as Quartz-Extreme. The breakthrough was achived by the programmer Jens von der Heydt.
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Controversy
Within five months of PearPC's release, another PowerPC emulator called CherryOS appeared claiming to offer more features and greater speed. However within hours of its announcement, questions were raised about the claims, with many experts and open-source advocates suggesting that CherryOS was nothing more than a repackaging of PearPC. The CherryOS Emulator was re-released in March 2005 as a commercial product. According to many experts, it still contained all or part of the code written for the PearPC Project. CherryOS also created questions regarding the legality of software developed and marketed specifically for the purpose of running Mac OS on the x86 architecture, since Apple's license agreement specifically states that the operating system may only be installed on Apple-'labeled' computers.
Shortcomings
At the time of writing, the current version of PearPC is 0.4pre (CVS). While its PowerPC emulation handles most applications and the emulator already has an impressive featureset, the project still lacks features needed for a complete emulation of the PowerPC experience:
- Sound emulation (Although a certain build of 0.4pre has this capability, it is fairly buggy.)
- G5 emulation (This would eventually be required if Apple decides to abandon compatibility for G3/G4 proccessors.)
- Direct access to the CD-ROM/DVD-ROM drives on Microsoft Windows™ operating systems is available only in some patched versions.
- .dmg support for use as an image (Currently to use a .dmg image you must first convert it into a larger .iso image with a program such as DMG2ISO)
Apple's CEO, Steve Jobs, announced on June 6th, 2005, that Apple will begin switching its computer architerture from IBM's PowerPC to Intel's x86 platform. The transition will take about 2 years to complete. The news raised alot of questions about the future of the PearPC project, because although the project itself is a PowerPC emulator, it is used primarily to run Mac OS X on x86 machines. If Mac OS X will run natively on the x86 platform, it is believed that the need for PearPC's emulation will eventually die.
Frontends
PearPC currently lacks its own GUI--the 'Change CD' button found in early versions has been eliminated because it never functioned correctly and many current builds include a native CD-Rom support patch. However, developers have made frontends for the program. Two of these are PearGUI, which looks like a Mac OS X application but is incompatible with current versions of PearPC, and PearPCCP (short for "PearPC Control Panel"), which is compatible with PearPC 0.3 and above. PearGUI's incompleteness annoys many users and its 'Create Disk Image' feature is not yet complete (a severe shortcoming), but many users have praised its GUI. PearPCCP has a built-in configuration wizard in addition to other advanced features, but is hindered by what many users believe to be an inferior interface and several bugs. Some users also report that PearPCCP removes comments from configuration files, while PearGUI does not. Cherry OS is strongly alleged to be simply a front end for PearPC, and its website was finally shut down in May, 2005.
See also
External links
- PearPC official website (http://pearpc.sourceforge.net)
- PearPC Web Forum (http://www.emaculation.com/phpBB/viewforum.php?f=21)
- PearPC nightly builds (http://www.richardgoodwin.com/pearpc/)
- Community-run PearPC Site. Includes RemoteCVS, which creates a PearPC executable from the current CVS (The CVS version is 0.4pre at the time of writing.) (http://www.pearpc.net)
- PearPC Community Forum (http://forums.pearpc.net/)de:PearPC