Steven G. Harris @stevengharris@mastodon.social
Public

Say what you want about the problems of social media today, but it’s kind of magical that I find a 50-year-old memo from Dan Ingalls announcing bitblt availability on the Alto coming across my Mastodon timeline, letting me send a “Happy 50th anniversary of bitblt for all those that celebrate” message to my former-Xerox-PARC buddy. mastodon.sdf.org/@fvzappa/1155

A scanned PARC-internal memo entitled "Bit BLT." The full document may be found here: https://www.bitsavers.org/pdf/xerox/alto/BitBLT_Nov1975.pdf

Crazy Eddie's Used Computers (@fvzappa@mastodon.sdf.org)

Attached: 1 image I declare that today, Nov. 19, 2025 is the 50th anniversary of BitBLT, a routine so fundamental to computer graphics that we don't even think about it having an origin. A working (later optimized) implementation was devised on the Xerox Alto by members of the Smalltalk team. It made it easy to arbitrarily copy and move arbitrary rectangles of bits in a graphical bitmap. It was this routine that made Smalltalk's graphical interface possible. Below is part of a PARC-internal memo detailing it:

mastodon.sdf.org · Mastodon @ SDF

0
0
0

If you have a fediverse account, you can quote this note from your own instance. Search https://mastodon.social/users/stevengharris/statuses/115578044994443572 on your instance and quote it. (Note that quoting is not supported in Mastodon.)