understanding the COLORXX regs...

Joe Maroni · 13 February 2005, 21:22

i tried to rip some original colors from several games with the help of the AR MKIII...

after typing "info" in the console i´ve got the values of the COLORXX registers...

i also understand that the first nibble is unused and the other following 3 nibbles tell me the RGB values...

but the reason is that one nibble can handle a maximum value of decimal 16...or hex f....

but most paint programs have slidebars that goes up to decimal 256...

maybe its a little bit confused, but can anyone tell how to solve this problem...???

if its written understandable enough...

Codetapper · 13 February 2005, 23:43

Action Replay handles 4 bit OCS/ECS colour values, from $000 to $fff. With AGA machines, you can use the full 8 bits for each RGB channel, thus $000000 to $ffffff.

If you are trying to recreate the palette on an AGA machine, you have to multiply each value by $11 (decimal 17) to get the corresponding colour. Thus 0 black becomes 0, 4 becomes $44 (decimal 68), 8 becomes $88 (decimal 136), $c becomes $cc (decimal 204) and $f becomes $ff (decimal 255).

I think quite a few programs just multiply by $10 but this means you miss out on the brightest shades of colours. ie. $f would become $f0. There is no perfect answer here but either multiply by $10 or $11 and you'll be OK.

Joe Maroni · 14 February 2005, 07:50

thanks...really helpful...

13 February 2005, 21:22	#1
Joe Maroni Moderator Join Date: Feb 2003 Location: Germany Age: 44 Posts: 1,303	understanding the COLORXX regs... i tried to rip some original colors from several games with the help of the AR MKIII... after typing "info" in the console i´ve got the values of the COLORXX registers... i also understand that the first nibble is unused and the other following 3 nibbles tell me the RGB values... but the reason is that one nibble can handle a maximum value of decimal 16...or hex f.... but most paint programs have slidebars that goes up to decimal 256... maybe its a little bit confused, but can anyone tell how to solve this problem...??? if its written understandable enough...

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13 February 2005, 23:43	#2
Codetapper 2 contact me: email only! Join Date: May 2001 Location: Auckland / New Zealand Posts: 3,182	Action Replay handles 4 bit OCS/ECS colour values, from $000 to $fff. With AGA machines, you can use the full 8 bits for each RGB channel, thus $000000 to $ffffff. If you are trying to recreate the palette on an AGA machine, you have to multiply each value by $11 (decimal 17) to get the corresponding colour. Thus 0 black becomes 0, 4 becomes $44 (decimal 68), 8 becomes $88 (decimal 136), $c becomes $cc (decimal 204) and $f becomes $ff (decimal 255). I think quite a few programs just multiply by $10 but this means you miss out on the brightest shades of colours. ie. $f would become $f0. There is no perfect answer here but either multiply by $10 or $11 and you'll be OK.

14 February 2005, 07:50	#3
Joe Maroni Moderator Join Date: Feb 2003 Location: Germany Age: 44 Posts: 1,303	thanks...really helpful...

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