About RTG refresh rate and color modes

[Leandro Jardim]

What means the RTG refresh rate box of WinUAE? Most Picasso96 setups of the 90 era would not work instead with 60Hz displays only? So everyone who wants it to be compatible with those systems should not need to change it to the option 60 instead? Or am I misunderstanding the real purpose of it's options?

What means each of the RTG color mode boxes? I know these are for color space conversion, but what I am unsure is what is their relation with the conversion itself. Looking for them, I would bet the first pair controls the high color conversion and the second the true color conversion, but I don't know if I am right because I never had a RTG board on my Amigas and in reality I am not a good coder too.

And because I never had an RTG board before, I am unsure what are the most commonly used options which the AmigaOS 3.x/4.x programs need and in what situations which I need to change them.

For my personal hardfile I have already chosen ahead the options 8bit, R5G6B5 for 16 bit high color and the options 24bit, R8G8B8 for 32 bit color, but I don't know what are the most common options chosen by the manufacturers of each video card, so I guess I can find problems when I install Picasso96 or try AmigaOS 4.x.

[Toni Wilen]

Originally Posted by Leandro Jardim

What means the RTG refresh rate box of WinUAE? Most Picasso96 setups of the 90 era would not work instead with 60Hz displays only? So everyone who wants it to be compatible with those systems should not need to change it to the option 60 instead? Or am I misunderstanding the real purpose of it's options?

It selects system reported refresh rate. Most programs don't care, some earlier RTG boards does not even support vblank interrupts (like Picasso II).

What means each of the RTG color mode boxes? I know these are for color space conversion, but what I am unsure is what is their relation with the conversion itself. Looking for them, I would bet the first pair controls the high color conversion and the second the true color conversion, but I don't know if I am right because I never had a RTG board on my Amigas and in reality I am not a good coder too.

It selects which modes are available. Defaults are optimal for emulation (little-endian BGR = no need to do conversions). No real RTG board supports all modes. If you change option, screenmode preferences mode type also changes.

Earlier RTG boards generally supported big-endian modes only (RGB), 24-bit mode was highest supported.
Later RTG boards only supported BGR modes, 32-bit mode replaced 24-bit modes. (32-bit being divisible by 4 makes it easier and faster in hardware)

Usually programs don't care but there are games that only work correctly with RGB modes.

[Leandro Jardim]

Thanks Toni. I will save this thread to my hard disk for me to never forget everytime I am in doubt.