3 ms·

Well, some rendering acceleration was with us from the very beginning in form of DMA (https://en.wikipedia.org/wiki/Direct_memory_access https://en.wikipedia.or

Well, some rendering acceleration was with us from the very beginning in form of DMA (https://en.wikipedia.org/wiki/Direct_memory_access https://en.wikipedia.org/wiki/Direct_memory_access) - transfer of blocks from RAM to VRAM. But that pretty much what we have now even on modern systems. For desktop UI purposes (but not for games) GPU acceleration started to become critical only relatively recently - on high-DPI screens. Number of pixels jumped 9 times between 96 ppi and 320 ppi (Retina) screens. CPUs haven't changed that much in the time frame so you may experience slow rendering on otherwise perfect screen picture.

rasz 6y ago
At the very beginning x86 PC computers didnt have DMA capable of transferring ram to ram, not to mention DMA was slower than CPU http://www.os2museum.com/wp/the-danger-of-datasheets/ http://www.os2museum.com/wp/the-danger-of-datasheets/ First PC 2D acceleration was very much on graphics chip, in form of either IBM 8514 or TIGA compatibility ($1K cards when introduced). Amiga also doesnt fit the profile, seeing most models shipped with unified shared memory (chip ram).
- boomlinde 6y ago
  > Amiga also doesnt fit the profile, seeing most models shipped with unified shared memory (chip ram). What profile? They did RAM to RAM DMA transfer exactly for video acceleration with the Agnus chip, which would access memory through DMA channels to perform 2D blitting.
  - rasz 6y ago
    c-smile specifically said 'RAM to VRAM'. Agnus/Alice didnt have DMA access to _non video_ ram so Amiga is automatically out. What I think he was thinking about was Blitter in general, and not particular implementations using DMA controller. First Blitter accelerated 2D graphics I read about were done on Xerox Alto using microcode.
    - boomlinde 6y ago
      I'm arguing from the point of view that 'VRAM to VRAM' (or maybe "shared I/O RAM" in Amiga's case) is a subset of 'RAM to VRAM'. You seem to be arguing from the point of view that just "RAM" in this context means non-video RAM. That's a fair assumption, and I understood it from your last post, but I don't think the difference is significant to the general point that we've had various forms of DMA-based 2D video acceleration for a long time.

rasz 6y ago

At the very beginning x86 PC computers didnt have DMA capable of transferring ram to ram, not to mention DMA was slower than CPU http://www.os2museum.com/wp/the-danger-of-datasheets/ http://www.os2museum.com/wp/the-danger-of-datasheets/ First PC 2D acceleration was very much on graphics chip, in form of either IBM 8514 or TIGA compatibility ($1K cards when introduced). Amiga also doesnt fit the profile, seeing most models shipped with unified shared memory (chip ram).

boomlinde 6y ago
> Amiga also doesnt fit the profile, seeing most models shipped with unified shared memory (chip ram). What profile? They did RAM to RAM DMA transfer exactly for video acceleration with the Agnus chip, which would access memory through DMA channels to perform 2D blitting.
- rasz 6y ago
  c-smile specifically said 'RAM to VRAM'. Agnus/Alice didnt have DMA access to _non video_ ram so Amiga is automatically out. What I think he was thinking about was Blitter in general, and not particular implementations using DMA controller. First Blitter accelerated 2D graphics I read about were done on Xerox Alto using microcode.
  - boomlinde 6y ago
    I'm arguing from the point of view that 'VRAM to VRAM' (or maybe "shared I/O RAM" in Amiga's case) is a subset of 'RAM to VRAM'. You seem to be arguing from the point of view that just "RAM" in this context means non-video RAM. That's a fair assumption, and I understood it from your last post, but I don't think the difference is significant to the general point that we've had various forms of DMA-based 2D video acceleration for a long time.