[HN Gopher] 12-minute Mandelbrot: fractals on a 50-year-old IBM ...
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       12-minute Mandelbrot: fractals on a 50-year-old IBM 1401 mainframe
        
       Author : winkywooster
       Score  : 20 points
       Date   : 2020-12-24 00:25 UTC (1 days ago)
        
 (HTM) web link (www.righto.com)
 (TXT) w3m dump (www.righto.com)
        
       | sliken wrote:
       | Only somewhat related, in 1986 or so computer labs at University
       | of Pittsburgh had giant printers, like 8 feet long with a maze
       | like paper path. They were however rather fast, something like
       | 60-90 pages a minute. The pages being spit out was a common sound
       | in the labs. They were however overwhelmingly used for ASCII. The
       | first page would be your username spelled large on the first page
       | out of ASCII.
       | 
       | I got interested in the Mandelbrot set, wrote it in pascal from
       | the original Scientific American article. Trick is I had no way
       | to view it. File quotas on the campus VAX were limited, so I
       | wrote a simple RLE compression. I looked into the Postscript
       | standard so I could write it myself, but was somewhat horrified
       | at the complexity. I had written PCL before. But I did find a
       | nice Fortran library. So I wrote some Fortran to read the RLE
       | picture file and output PostScript.
       | 
       | Some afternoon near Xmas, I tried it out. I had no idea if it
       | would work since I couldn't debug it, there was no postscript
       | viewers (or graphical terminals) available. I printed the
       | postscript file and the printers sudden page per second stopped.
       | After a few seconds the operator jumped up and was about to reset
       | the printer. I pleaded my case for a few minutes, the operator
       | agreed, and a 300 DPI Mandelbrot was spit out. The operator went
       | "Woah!", a few more people in the lab saw it and impressed. I
       | explained what a fractal was and that you could zoom in
       | infinitely. Several people wanted copies, so I printed them. The
       | entire process took many minutes (pascal to generate, fortran to
       | render, and print to print). These days you can zoom way deeper
       | and get at least 60 FPS.
       | 
       | Later I wrote a EGA driver in Turbo Pascal, primarily for
       | Mandelbrot viewing and a few simple games I wrote. I was able to
       | do so from an article in the PC Tech Journal which printed the
       | entire EGA card spec. Later I wrote the ASM for an 8087, then a
       | HP-730 (PA-RISC 1.0) and a small tweak for the HP-735 (PA-RISC
       | 1.1).
        
       | h2odragon wrote:
       | > additional instructions were available for a rental fee
       | 
       | The wet dream of chipmakers today, no doubt. Most recent example
       | that occurs to me is the VideoCore bullshit on Raspi, afaik the
       | effect was few paid for a license and that hardware feature
       | mostly went unused before it went obsolete.
        
         | kens wrote:
         | I should point out that the additional instructions in the IBM
         | 1401 required additional hardware, so you weren't paying for
         | IBM to move a jumper.
         | 
         | For instance, the multiply/divide feature cost $333 per month
         | (in 1960s dollars), but it required the installation of 183
         | circuit boards (each the size of a playing card) so you were
         | getting your money's worth.
         | 
         | More curious was the Sterling currency option, which provided
         | arithmetic in pounds/shillings/pence. (I.e. 12 pence to the
         | shilling, 20 shillings to the pound.) This required 508 new
         | circuit boards, but made it much easier to do currency math in
         | England. Keep in mind this is transistor circuitry to do math
         | in hardware.
        
         | walshemj wrote:
         | After a substatial hardware upgrade though - those of us who
         | are old enough remember when IBM PC's came with a empty chip
         | socket for the Intel 8087
        
         | colejohnson66 wrote:
         | You mean the hardware license keys for the MPEG-2 decoder? That
         | was very stupid, but I bet it was something the Raspberry Pi
         | people had to do to make the board cheaper (probably through
         | cheaper SoC). So rather than paying (fake numbers here) $5 per
         | processor IC, they paid $3 with the decoder option available.
         | 
         | It sucked at the time, but thankfully the later Raspberry Pi 3B
         | was powerful enough that that wasn't needed anymore (it was
         | still available on the 3B, but IDK about the 4B).
        
           | userbinator wrote:
           | ...and there is a crack available for that, not surprisingly.
        
       | wolfgang42 wrote:
       | (2015); discussed at the time:
       | https://news.ycombinator.com/item?id=9243163
        
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       (page generated 2020-12-25 23:00 UTC)