[Reverse-engineering] 32-bit VRAM plane pointers
I've looked at every openly available piece of PC-98 documentation, and there
don't seem to be any official names for the individual planes. The closest
thing I could find was the description at
http://island.geocities.jp/cklouch/column/pc98bas/pc98disphw2.htm
explaining that they represent the blue, red, green, and brightness component
when using the default PC-98 palette. However, these planes correspond to
nothing else but the 4 individual bits of the final index into the color
palette, and you can assign any color to every single palette slot. Therefore,
it's merely a convention that your own palettes don't have to follow (and in
Touhou, they don't).
Nevertheless, there doesn't seem to be an alternative, and the Neko Project II
source code uses the same B/R/G/E convention, so I'll go with that as well.
2015-02-10 22:43:34 +00:00
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; void vram_planes_set(void)
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vram_planes_set proc
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push bp
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mov bp, sp
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2015-02-24 15:17:50 +00:00
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mov _VRAM_PLANE_B, 0A8000000h
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mov _VRAM_PLANE_R, 0B0000000h
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mov _VRAM_PLANE_G, 0B8000000h
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mov _VRAM_PLANE_E, 0E0000000h
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[Reverse-engineering] 32-bit VRAM plane pointers
I've looked at every openly available piece of PC-98 documentation, and there
don't seem to be any official names for the individual planes. The closest
thing I could find was the description at
http://island.geocities.jp/cklouch/column/pc98bas/pc98disphw2.htm
explaining that they represent the blue, red, green, and brightness component
when using the default PC-98 palette. However, these planes correspond to
nothing else but the 4 individual bits of the final index into the color
palette, and you can assign any color to every single palette slot. Therefore,
it's merely a convention that your own palettes don't have to follow (and in
Touhou, they don't).
Nevertheless, there doesn't seem to be an alternative, and the Neko Project II
source code uses the same B/R/G/E convention, so I'll go with that as well.
2015-02-10 22:43:34 +00:00
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pop bp
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ret
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vram_planes_set endp
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