Nintendo 1504166 - Game Boy Advance SP Edition Console Programming Manual page 81

AGB Programming Manual
In addition, semi-transparent OBJs are individually specified in OAM, and color special
effects for the OBJ as a whole, are specified in the BLDCNT register. These
specifications are summarized in the following table.
BLDCNT
Type
d07 d06
0 0 No special effects
0 1 blending
(Semi-transparency
processing)
1 0 Brightness Increase Gradually increases brightness for 1
1 1 Brightness
Decrease
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Color Special Effects Processing
Normally, color special effects processing is not performed.
16-level semi-transparency processing ( blending) is performed only
when a semi-transparent OBJ is present and is followed immediately
nd
by a 2 target screen.
st
If the 1 target screen is followed immediately by a 2
16-level semi-transparency processing ( blending) is performed.
The bits of the backdrop of the 1
([d05]=0).
st
When OBJ = 1 for the 1 target pixel, processing is executed for all
OBJs regardless of the OBJ type.
When OBJ=0, processing is executed only if the OBJ is semi-
transparent.
The entire screen can gradually be made whiter by setting all bits of
the specification for the 1st target screen to 1.
When OBJ=1 for the 1st target screen, processing for increased
brightness is executed only for normal objects.
If a semi-transparent OBJ is the 1st target screen,
processing is always executed.
Brightness is gradually decreased for the 1st target screen.
The entire screen can gradually be made blacker by setting all bits of
the specification for the 1st target screen to 1.
When OBJ=1 for the 1st target screen, processing for decreased
brightness is performed only for normal objects. If a semi-transparent
OBJ is the 1st target screen,
executed.
81
nd
target screen,
st
target screen should be turned off
st
target screen.
blending
blending processing is always
D.C.N. AGB-06-0001-002B4
Color Special Effects