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Graphics > Palette RAW data documentation?

#187 - zanor - Sat Jan 04, 2003 10:57 pm

Is there any documents on the RAW palette file format on the net?

Thanks!

#199 - Burre - Sun Jan 05, 2003 3:01 am

Dunno, but isn't it just 15bit color (5bit + 5bit + 5bit)? X111 1111 1111 1111

Or?
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#221 - marschild - Sun Jan 05, 2003 5:57 am

in the gba you store it reversed as bgr, though (just stating the obvious)
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#225 - Splam - Sun Jan 05, 2003 8:34 am

It's BGR on gba and afaik (not really tested it myself yet as it won't really make much difference) there is an extra bit for green so its 1,5,5,5 G,B,G,R with the top bit of the palette entry actually being the bottom bit of green ie 1,5 bits which actually becomes 5,1 (to make 6 bits) crazy eh hehe

#226 - Costis - Sun Jan 05, 2003 8:55 am

Hi,

No, there isn't any extra green bit. The MSB of the half-word (15th bit starting from 0) is unused. Then the rest of the bits are split up into 5 bit color units following the BGR format. You could say that the format of one palette entry is: 1U-5B-5G-5R where U is unused, B is blue, G is green, and R is red.

Costis

#233 - Burre - Sun Jan 05, 2003 12:47 pm

marschild wrote:
in the gba you store it reversed as bgr, though (just stating the obvious)


:) true. I ment counting from LSB, but drawed it reversed. Shit happens when you're low on coffein and are up and running when you're supposed to be counting sheep.
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#234 - Splam - Sun Jan 05, 2003 12:53 pm

Costis wrote:
Hi,

No, there isn't any extra green bit. The MSB of the half-word (15th bit starting from 0) is unused. Then the rest of the bits are split up into 5 bit color units following the BGR format. You could say that the format of one palette entry is: 1U-5B-5G-5R where U is unused, B is blue, G is green, and R is red.

Costis


It seems to depend on where you get your documents from for this extra green bit, the official nintendo one I got says it's there, but an older version of the same document doesn't have anything about it..

#236 - Burre - Sun Jan 05, 2003 1:13 pm

Splam wrote:

It seems to depend on where you get your documents from for this extra green bit, the official nintendo one I got says it's there, but an older version of the same document doesn't have anything about it..


Hmm, strange. However, I've heard of ppl utilizing the extra bit in the format to process higher resolution graphics (color depth). Not sure how, but probably using the bit as a 'toggle' to enable the double amount of colors (2 x 15bit) or so, but now I'm just guessing.
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#249 - zanor - Sun Jan 05, 2003 3:45 pm

OK, Thanks! I think I understand it now...

#440 - anli - Tue Jan 07, 2003 6:45 pm

I was trying if the extra bit actually is making any difference.
I also played with the register 0x4000002 (green swap).

I thought, maybe enabling a certain bit in that register can turn on
the 6-bit green feature.

However, with or without the extra 6th "green" bit, there is no difference.

My test result can be found at

http://www.anderslinden.net/~anli/16palette_test.gba


/anli