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 relatively soon. Individuals are making builds with more features like native CD-ROM support and even progress in emulating sound has begun. Popular PearPC sites that provide builds also include Altivec support for PowerPC G4 processors. Support for graphics cards acceleration is in progress, which in theory should provide a major performance boost due to OS X's hardware-accelerated GUI known as Quartz-Extreme.
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[edit] CherryOS 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 commercial 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. Eventually, CherryOS died due to the very high amount of criticism that had been directed at it.
[edit] Shortcomings
The current version of PearPC is 0.4.0 (as of October 01, 2006). While its PowerPC emulation handles most applications and the emulator already has an impressive feature set, 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 (Not necessary because Rosetta, Apple's PowerPC runtime environment on Mac, only runs G3 and G4 applications)
- .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 architecture from IBM's PowerPC to Intel's x86 platform. The transition was completed in August of 2006. The news raised a lot 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, PearPC's emulation may possibly be replaced by VMWare (which has announced a version of their software for Intel Macs [1]) or other virtualization products. However, it has been confirmed that OS X will not run out of the box on standard PCs.
[edit] Frontends
PearPC currently lacks its own GUI — the 'Change CD' button found in early versions has been eliminated because it rarely functioned correctly. 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. The PearPC.net website also released its own Java-based PearPC-GUI, called PearPC.net Package. CherryOS is alleged to be simply a front end for PearPC. Its website was shut down in May 2005. There is also APE, written in Java by two staff members of PearPC.net, Alex and camouflageX.
