The paper Rob refers to is https://dl.acm.org/doi/10.1145/363347.363368 -Henry On Mon, 6 Mar 2023 at 03:57, Rob Pike wrote: > I would think you have read Sutherland's "wheel of reincarnation" paper, > but if you haven't, please do. What fascinates me today is that it seems > for about a decade now the bearings on that wheel have rusted solid, and no > one seems interested in lubricating them to get it going again. > > -rob > > > On Mon, Mar 6, 2023 at 7:52 PM Paul Ruizendaal via TUHS > wrote: > >> Thanks for this. >> >> My question was unclear: I wasn't thinking of the hardware, but of the >> software abstraction, i.e. the device files living in /dev >> >> I’ve now read through SunOS man pages and it would seem that the /dev/fb >> file was indeed similar to /dev/fbdev on Linux 15 years later. Not quite >> the same though, as initially it seems to have been tied to the kernel part >> of the SunWindows software. My understanding of the latter is still limited >> though. The later Linux usage is designed around mmap() and I am not sure >> when that arrived in SunOS (the mmap call exists in the manpages of 4.2BSD, >> but was not implemented at that time). Maybe at the time of the Sun-1 and >> Sun-2 it worked differently. >> >> The frame buffer hardware is exposed differently in Plan9. Here there are >> device files (initially /dev/bit/screen and /dev/bit/bitblt) but these are >> not designed around mmap(), which does not exist on Plan9 by design. It >> later develops into the /dev/draw/... files. However, my understanding of >> graphics in Plan9 is also still limited. >> >> All in all, finding a conceptually clean but still performant way to >> expose the frame buffer (and acceleration) hardware seems to have been a >> hard problem. Arguably it still is. >> >> >> >> > On 5 Mar 2023, at 19:25, Kenneth Goodwin >> wrote: >> > >> > The first frame buffers from Evans and Sutherland were at University of >> Utah, DOD SITES and NYIT CGL as I recall. >> > >> > Circa 1974 to 1978. >> > >> > They were 19 inch RETMA racks. >> > Took three to get decent RGB. >> > >> > 8 bits per pixel per FB. >> > >> > On Sun, Mar 5, 2023, 10:02 AM Paul Ruizendaal via TUHS >> wrote: >> > I am confused on the history of the frame buffer device. >> > >> > On Linux, it seems that /dev/fbdev originated in 1999 from work done >> by Martin Schaller and Geert Uytterhoeven (and some input from Fabrice >> Bellard?). >> > >> > However, it would seem at first glance that early SunOS also had a >> frame buffer device (/dev/cgoneX. /dev/bwoneX, etc.) which was similar in >> nature (a character device that could be mmap’ed to give access to the >> hardware frame buffer, and ioctl’s to probe and configure the hardware). Is >> that correct, or were these entirely different in nature? >> > >> > Paul >> > >> >>