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Amazing demos are released on the C64 today. High quality productions spanning several disk sides, still pushing the boundaries of the machine and doing things

Amazing demos are released on the C64 today. High quality productions spanning several disk sides, still pushing the boundaries of the machine and doing things like playing video streamed from floppy, using the SID chip for sample playback with incredible quality, squeezing the last out of every single byte of RAM. It shows how well the authors know the system. Many of them have coded for it for more than 30 years and know every little bit about it by heart. Still, those demos couldn't have been created on an unexpanded C64 without the help of modern cross-development: running an assembler natively takes up memory that can now be freed for data and code. The same goes for some of the audio and graphics: using a PC to downsample from a higher resolution yields better quality and those resolutions wouldn't fit on a floppy, let alone the unexpanded memory. Some of it could maybe be done natively with a RAMLink and hard drive, but not all of it.

wiz21c 6y ago
Yep, special use case : data compression. Many compression that work on old computer are actually the decompression side of an asymmetric compression scheme. Asymmetric meaning that it requires a lot more CPU power than a mere C64 can provide to compress data whereas the same C64 can easily decompress... I've coded myself a Bad Apple video demo for the Apple 2+. Takes minutes of compression on my I7 but can be decrunched on a 1Mhz 6502.
- Retric 6y ago
  If computers stop getting faster then larger investments in software development become reasonable. As we are not limited to a single i7 today, the C64 was hardly the most powerful machine of that time. A Cray X-MP released just after the C64 might take hours to run that same compression, which would have been expensive but hardly impossible.
  - eggsome 6y ago
    A Cray X-MP could only do 800 flops. Even a first gen i7 is many orders of magnitude better than that.
    - Retric 6y ago
      That’s 800 Megaflops not flops. First an i7 920 is up to 54,000 megaflops vs a cray X-MP at 800 MFlops X minutes on a first gen i7 is ~1.1 hours in terms of pure flops. However, that i7’s architecture has many compromises that tend to make it significantly less efficient. Newer i7’s have significantly more power, but it’s still few minutes > Y hours not days or anything.
      - needle0 6y ago
        Though not many people would've had have access to a Cray X-MP back in its time, and certainly not to use it for compression in creating a hobbyist Apple II demo that's not expected to generate any profit. Again, possible in theory, but impractical in its day and age.
        Retric 6y ago
        That’s fair, but if we assume hardware stalls for say 1,000 years you get a different ROI from computer investments. 6 hours on a 30 million dollar supercomputer that lasts for 20 years is ~1,000$ worth of it’s lifespan + electricity costs etc. Over time you can expect various people to have made such investments and historic examples would still be valuable on “modern” hardware.

wiz21c 6y ago

Yep, special use case : data compression. Many compression that work on old computer are actually the decompression side of an asymmetric compression scheme. Asymmetric meaning that it requires a lot more CPU power than a mere C64 can provide to compress data whereas the same C64 can easily decompress... I've coded myself a Bad Apple video demo for the Apple 2+. Takes minutes of compression on my I7 but can be decrunched on a 1Mhz 6502.

Retric 6y ago
If computers stop getting faster then larger investments in software development become reasonable. As we are not limited to a single i7 today, the C64 was hardly the most powerful machine of that time. A Cray X-MP released just after the C64 might take hours to run that same compression, which would have been expensive but hardly impossible.
- eggsome 6y ago
  A Cray X-MP could only do 800 flops. Even a first gen i7 is many orders of magnitude better than that.
  - Retric 6y ago
    That’s 800 Megaflops not flops. First an i7 920 is up to 54,000 megaflops vs a cray X-MP at 800 MFlops X minutes on a first gen i7 is ~1.1 hours in terms of pure flops. However, that i7’s architecture has many compromises that tend to make it significantly less efficient. Newer i7’s have significantly more power, but it’s still few minutes > Y hours not days or anything.
    - needle0 6y ago
      Though not many people would've had have access to a Cray X-MP back in its time, and certainly not to use it for compression in creating a hobbyist Apple II demo that's not expected to generate any profit. Again, possible in theory, but impractical in its day and age.
      - Retric 6y ago
        That’s fair, but if we assume hardware stalls for say 1,000 years you get a different ROI from computer investments. 6 hours on a 30 million dollar supercomputer that lasts for 20 years is ~1,000$ worth of it’s lifespan + electricity costs etc. Over time you can expect various people to have made such investments and historic examples would still be valuable on “modern” hardware.