@ppcamiga1

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ppcamiga1 wrote: OCS was wonderfull. ECS was ok. After ECS C= should provide new chipset chunky oriented working in parallel to ECS. Any further work on old chipset was wrong. They should leave ECS as it is and start from scratch new graphics for Amiga.

@cdimauro

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cdimauro wrote: This is another example of using the brute force / CPU to overcome the limits of the Amiga chipset, for a regular task for this machine (e.g.: 2D game). Which wasn't clearly the way to go: the chipset was the central element of the system, offloading most of the work from the CPU. Quote: 1990s-era mainstream Japanese game consoles and PC VGA have discrete video memory. The same for the Amiga was possible, but that's not the point with this system. The Amiga could have evolved its chipset to remain competitive with both, while keeping its philosophy (as I've already proven on my last series of articles). But the engineers which remained after that the original ones left lacked both knowledge and vision.

The original engineers lacked knowledge and vision too. Jay Miner wanted high resolution monochrome for 'workstation' graphics like Sun had. He didn't think about having 256 colors, bigger sprites or increasing the colors and resolution in dual playfield and HAM modes. He seemed to have completely lost interest in the Amiga's gaming and multimedia capabilities.

Luckily for us some of the 'engineers who were left' had a different focus. Unfortunately they were sidelined by those who wanted AAA's expensive 'professional' graphics, delaying AGA for a critical year that made it a bit too late to compete against PCs with VGA. They did manage to get it out in time to produce good quantities of the A1200 and CD32, but it would have been so much better if Commodore had survived long enough to get AGA+ out.

@bhabbott

> Jay Miner wanted high resolution monochrome for 'workstation' graphics like Sun had.

Well an additional Hires mode in the OCS chipset could have helped, but the biggest problem with hires was keeping a screen ratio of 4:3 without interlace, back then in 1984 a VGA like resolution with 60Hz would have been welcome.

On the other hand some engineers wanted to have a HAM mode with a real YUV mode, this would have been great for 'natural' color images but a disaster for programming if it had affected the other screen modes.

@OneTimer1

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OneTimer1 wrote: @bhabbott > Jay Miner wanted high resolution monochrome for 'workstation' graphics like Sun had. Well an additional Hires mode in the OCS chipset could have helped, but the biggest problem with hires was keeping a screen ratio of 4:3 without interlace, back then in 1984 a VGA like resolution with 60Hz would have been welcome.

This thread is about games, where even purpose-built arcade machines were running in 'low' resolution.

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On the other hand some engineers wanted to have a HAM mode with a real YUV mode, this would have been great for 'natural' color images but a disaster for programming if it had affected the other screen modes.

It wouldn't have, so this wasn't an issue. The problem was converting YUV to RGB, which is tricky to do accurately in the digital domain.

The alternative would be to output YUV and convert to RGB with an external analog circuit, which is what some other video chips needed to get RGB. This could actually be done on a stock Amiga by interpreting the RGB analog outputs as YUV and treating them accordingly. For example you could assign Y to green, U to blue and V to red, and feed the RGB channels directly into a composite modulator. Then HAM 'modify green' would set the Y value, 'modify blue' would set U, and 'modify red' would set V. The 16 base colors would have their palette entries interpreted as YUV values. This could done in other screen modes too, converting the entire system to YUV. The extra hardware required is just a standard YUV to composite encoder (as used in the ZX Spectrum etc.) plugged into the RGB video port.

Here's where it gets crazy. Commodore changed the Amiga chipset to RGB so they could use a high resolution RGB monitor for sharper text etc. But the 1080 monitor supplied with the A1000 also had composite input, which was demodulated to YUV and then converted to RGB inside the monitor.

Commodore could have stuck with the original Amiga design and provided the 1080 monitor with YUV 'component' inputs like later TV sets had, producing a sharp picture with a 'better' HAM mode. Why didn't they? Because they wanted the Amiga to work with 'standard' RGB monitors. This turned out to be a good decision because RGB did become the standard for computer monitors, and for TVs in Europe with SCART. Component inputs started appearing on TVs in the late 90s, then disappeared again as HDMI took over.

@bhabbott

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bhabbott wrote: This thread is about games, where even purpose-built arcade machines were running in 'low' resolution.

I apologize for my OT sentence.

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The alternative would be to output YUV and convert to RGB with an external analog circuit, which is what some other video chips needed to get RGB. This could actually be done on a stock Amiga by interpreting the RGB analog outputs as YUV and treating them accordingly. For example you could assign Y to green, U to blue and V to red, and feed the RGB channels directly into a composite modulator.

Yes, you can do it with analog circuits, but switching between the RGB image and YUV would have needed complicated circuits and the only benefit would have been a nicer HAM mode.