You should be able to emulate close to CRT beam scanout + phosphor decay given high enough refresh rates.
Eg. given a 30 Hz (60i) retro signal, a 480 Hz display has 16 full screen refreshes for each input frame, while a 960 Hz display has 32. 480 Hz already exists, and 960 Hz are expected by end of the decade.
You essentially draw the frame over and over with progressive darkening of individual scan lines to emulate phosphor decay.
In practice, you'd want to emulate the full beam scanout and not even wait for full input frames in order to reduce input lag.
Mr. Blurbuster himself has been pitching this idea for awhile, as part of the software stack needed once we have 960+ Hz displays to finally get CRT level motion clarity. For example:
> Eg. given a 30 Hz (60i) retro signal, a 480 Hz display has 16 full screen refreshes for each input frame, while a 960 Hz display has 32. 480 Hz already exists, and 960 Hz are expected by end of the decade.
Many retro signals are 240p60 rather than 480i60. Nearly everything before the Playstation era.
Eg. given a 30 Hz (60i) retro signal, a 480 Hz display has 16 full screen refreshes for each input frame, while a 960 Hz display has 32. 480 Hz already exists, and 960 Hz are expected by end of the decade.
You essentially draw the frame over and over with progressive darkening of individual scan lines to emulate phosphor decay.
In practice, you'd want to emulate the full beam scanout and not even wait for full input frames in order to reduce input lag.
Mr. Blurbuster himself has been pitching this idea for awhile, as part of the software stack needed once we have 960+ Hz displays to finally get CRT level motion clarity. For example:
https://github.com/libretro/RetroArch/issues/6984