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Thanks to Adobe and the Computer History Museum, the source code of Photoshop version 1.0.1 for Mac is now available for non-commercial use.
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Now that we have the Photoshop source code
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This release has all of the Photoshop code, but it doesn’t include the MacApp library licensed from Apple, so some additional work is needed to get it into a fully functional state. Contained in roughly 128,000 lines, the download is a mere 601KB zipped. Expanded, it’s about 2.7MB. It’s estimated that three-fourths of the code is written in Pascal while 15% of it is written in 68000 assembler language. As for the remaining 10%, that’s taken up by miscellaneous data. The code is uncommented, but at least the devs had the decency to keep it formatted cleanly.
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