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8088 MPH: We Break All Your Emulators

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Re: 8088 MPH: We Break All Your Emulators

#21

Post by pja »

blackhaz wrote: post #3

I can't believe my eyes. 256 colors on CGA?! HOW?!

I believe you can manipulate the colour bleed between pixels on the composite output from a high resolution mode to achieve high-colour output. (They actually have a 1024-colour mode in part of the demo.)

There are probably a bunch of weird limitations on the adjacent colours you can achieve, but it’s an impressive effect regardless!

(Here’s the obligatory wikipedia page: https://en.wikipedia.org/wiki/Composite_artifact_colors It sounds like the demo developers have taken this effect & turned it up to 11.)

Re: 8088 MPH: We Break All Your Emulators

#22

Post by chipsy »

ekianjo wrote: post #17
blackhaz wrote: post #3

I can't believe my eyes. 256 colors on CGA?! HOW?!

The Amiga had such tricks as well to display 4096 colors at the same time on screen while it could only display up to 32 specs wise. Not sure how they do it on PC, but there's probably a way to achieve it as well.

CGA's "Composite" mode contains output artifacts, a trait also found in other early microcomputer graphics like those of the Apple II or Atari 800; with careful use of dithering, CGA can be expanded to a larger effective gamut[0] although most games wouldn't be as ambitious as this demo. It's not as well-known or used as the 4-color modes because it wasn't supported by later PC graphics adapters, nor was it in the spec of the standard monitors of the era. You can see this system struggle to reproduce the demo's intended look: [1]

[0] Example: https://www.youtube.com/watch?v=TfVe9l77zLU

[1] https://www.youtube.com/watch?v=aibZKrXc8Nk

Re: 8088 MPH: We Break All Your Emulators

#23

Post by ekianjo »

frooxie wrote: post #19
ekianjo wrote: post #17

Earlier quoted context omitted.

The Amiga had such tricks as well to display 4096 colors at the same time on screen while it could only display up to 32 specs wise. Not sure how they do it on PC, but there's probably a way to achieve it as well.

The 4096 color HAM mode was always part of the spec.

yes, it is, but it can only be used in very specific conditions (you cannot have the colors where you want all over the place), it's a pure hack.

Re: 8088 MPH: We Break All Your Emulators

#25

Post by azinman2 »

ekianjo wrote: post #16
skrebbel wrote: post #9

Earlier quoted context omitted.

Stop generalizing. Plenty will.

> Stop generalizing. Plenty will. Look at modern forum discussions on Smartphones, it's full of youngsters comparing specs of their respective phones without grasping at all what they mean. Or maybe you are referring to a highly educated subset of youngsters, but that's very few of them.

This is HN, not Facebook.

Re: 8088 MPH: We Break All Your Emulators

#26

Post by Zardoz84 »

pja wrote: post #21
blackhaz wrote: post #3

I can't believe my eyes. 256 colors on CGA?! HOW?!

I believe you can manipulate the colour bleed between pixels on the composite output from a high resolution mode to achieve high-colour output. (They actually have a 1024-colour mode in part of the demo.) There are probably a bunch of weird limitations on the adjacent colours you can achieve, but it’s an impressive effect regardless! (Here’s the obligatory wikipedia page: https://en.wikipedia.org/wiki/Composite_artif…

I remember that "extra colours" could be archived on a ZX Spectrum using the bleed of the RF or composite output.

Re: 8088 MPH: We Break All Your Emulators

#27

Post by draugadrotten »

blackhaz wrote: post #3

I can't believe my eyes. 256 colors on CGA?! HOW?!

On Atari ST, it was possible to change the palette colors in midflight, and using that trick to display more colors on screen. The technique was used by Spectrum 512 and Quantum Paint and many demos.

"QPs 512 mode is pretty straightforward; its only color limitation being that it can display a maximum of 40 colors on a single scan line. Mode 4K uses a special technique called "interlacing" in order to display a supposed 4,096 "colors -- http://www.atarimagazines.com/startv3n2/quantumpaint.html see also http://www.atari-wiki.com/index.php/ST_Picture_Formats

Re: 8088 MPH: We Break All Your Emulators

#29

Post by geocar »

ekianjo wrote: post #15
geocar wrote: post #10

Earlier quoted context omitted.

Your game could dynamically modify the instructions.

Sure, but wouldn't that incur a loss of performance ?

Some, but maybe not very much: The screen is redrawn much more frequently than a key is pressed.
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