Super High Res

[blakespot]

Quarter-pixel scrolling games benefit from this ability.

Can you point to a single game that utilizes this mode? I am pretty sure there are none.

Its only practical use is for video titling software, some of which I know supported the mode.




bp

[Crumb]

Can you point to a single game that utilizes this mode? I am pretty sure there are none.

Its only practical use is for video titling software, some of which I know supported the mode.




bp

WORMS DC is the first one that comes to my mind, also Morton Strikes Back and Fantastic Dizzy AGA. I'm sure that there are more AGA versions that use quarter pixel scroll (but I'm not much into games, honestly)

But there's something that uses SuperHires everytime: scene demos with pseudo true color screenmodes. These use SuperHires HAM8 resolution to achieve an screen a quarter the width.

[Leffmann]

Can you point to a single game that utilizes this mode? I am pretty sure there are none.

Its only practical use is for video titling software, some of which I know supported the mode.

Virtual Karting and Virtual Karting II use super hires in a pretty elaborate way, akin to how LCD screens work with red, green and blue subpixels.

AGA also outputs at 35ns pixel resolution (super hires) at all times regardless of what the screen resolution is, and games running on AGA can benefit from this for free by adjusting the position of hardware sprites and hardware-scrolled screens with super hires accuracy.

I don't know how modern LCD screens handle these things, but on CRT screens these narrow pixels and differences usually blend together but still give a perceived increase in image quality.

[thedocbwarren]

Sounds like you're using a digital monitor - since it's digital it samples the analogue signal and outputs what's been sampled. If the sampling rate is too low (only half of pixel frequency) every other pixel gets lost. As it seems, your monitor has no idea that the Amiga is outputting such a high pixel rate.

Look at the way a video output or (analogue) monitor works: the video hardware just outputs a stream of pixels; for Lores they're 140 ns apart (long), for Hires 70 ns and for SuperHires just 35 ns. In the monitor these pixels modulate an electron beam that scans the screen, moving from left to right. After some time - when the desired line length is reached - a horizontal sync pulse tells the monitor to quit scanning horizontally but move to the next line directly underneath and rewind to the left edge. When the desired frame height is reached a vertical sync pulse tells the monitor to rewind the scanning beam to the top left corner to start the next frame.

A fixed frequency monitor has a constant scan rate to make the beam cover the whole screen during a horizontal or a full vertical sweep. A multisync monitor has to track the vertical and horizontal sync rates and adjusts the sweep rates accordingly.



A digital (flat) monitor is more complex. It samples (A/D converts) the analogue signal into a buffer. To make sure none of the pixels gets lost it's required to pretty exactly match the sampling rate to the pixel rate by using an edge detection algorithm. Note that this exactly the way a flickerfixer works - in theory all flat screen integrate one, but in real life they're usually limited by the extent they can adapt to the signal.

The buffered image (hopefully resembling the original signal) is then output to the display matrix. On LCD screens there's no sweeping beam but rather a continuous memory matrix that you look at, thus the susceptibility to jitter and jerking.

Ok that I get.  So the pixels are crammed in there of which the signal picks up as much as it can for a scan.  This, I assume, is the chroma resolution?

So it seams then the Amiga is packing the signal vs doubling it to get a higher resolution.  I can see how most monitors are unlikely to support this.

[ChaosLord]

So it seams then the Amiga is packing the signal vs doubling it to get a higher resolution.  I can see how most monitors are unlikely to support this.

1280 pixel mode is a bog standard video mode.

Any monitor that doesn't support it is either
A: A ripoff piece of crap
B: Very very very old
C: Broken

[ChaosLord]

I'm bloody confused with all that.  So I have an AGA Amiga (1200) and the mode 'works' just looks blurry.

Ok.  What kind of monitor are you using?  LCD or CRT?

So I think I userstand the ide behind keeping it 200-256 lines to keep compatibility with broadcast, but I don't understand 1280 if it's not 1280.

It is 1280 pixels.  There is nothing fake about it.

It's not  a 30Hz mode so I don't quick get what's doubled if it's not really 1280 pixels across?

It is absolutely 1280 pixels across.

What's faster about 16 colours?  I thought it was restricted to 4?

On AGA:
1280 mode is not restricted to 4 colors.
1280 mode is not restricted to 16 colors.
1280 mode is not restricted to 256 colors.
1280 mode can use the full 16 million color palette in HAM8 mode, which is the main purpose of 1280 mode: viewing photographs in 16 million colors.

1280 mode is not restricted to 200/256 pixels height.  It can also do 400/512 pixels high.  When I use 1280 mode I use 1280x512.

[sledge]

1280 pixel mode is a bog standard video mode.

Any monitor that doesn't support it is either
A: A ripoff piece of crap
B: Very very very old
C: Broken

Yes, 1280x256 and 1280x512 interlaced works on every PAL monitor and TV that I have. It's the same kHz and Hz as the normal PAL or NTSC modes. No scandoubling no nothing... just plain PAL/NTSC.

It looks truly amazing on a PAL LCD TV since those monitors doesn't show the flickering that the Interlace mode produce.

[ChaosLord]

well, it works but its barely usable.

It is the most usable mode there is for viewing photographs.

Have you ever heard of a thing called "porn"?

[ChaosLord]

In reality, 1280x200/256 is hardly ever used.

That is because 1280x512 is so much better.

[Crumb]

That is because 1280x512 is so much better.

yeah! and SuperHiResLaced+Overscan is even more impressive with 1444x576 pixels :-)

As you have explained, SHiRes doesn't have any colour limitation but just like 31Khz screenmodes it requires more DMA channels to work and with 8 bitplanes it will be slower than 4 bitplane screens because cpu has less time to access chipram.

[Crumb]

I can see how most monitors are unlikely to support this.

I never found a 15khz monitor/TV that didn't support it.

[Zac67]

So the pixels are crammed in there of which the signal picks up as much as it can for a scan.  This, I assume, is the chroma resolution?

It's chroma as well as luma resolution, RGB doesn't make a difference.

So it seams then the Amiga is packing the signal vs doubling it to get a higher resolution.  I can see how most monitors are unlikely to support this.

All analogue monitors do support this mode - they simply don't have a choice. If you're not able to see every single pixel it's because the monitor's resolution/dot pitch 'swallows' part of the signal or by signal degradation (double pixel clock requires double bandwidth). Most digital monitors probably sample only every other pixel, assuming a 640 resolution, so each sampled pixel blots out its successor.