AGB Programming Manual
Rendering Functions
©1999 - 2001 Nintendo of America Inc.
50
D.C.N. AGB-06-0001-002B4
Parameters used in rotation and scaling operations are specified for BG2
and BG3 in the following registers. Registers for Starting Point of BG Data
Reference are also used when Scaling/Rotation BG and Bitmap Mode BG
are offset displayed (scrolled). (There is also an offset register for Text
BG.)
Registers for Setting the Starting Point of BG Data
15
14 13
12
11 10
09
08 07
06
05 04
03
02 01
00
BG2X_L
BG3X_L
028h
038h
0000h
W
Address
Register
AttributesInitial Value
X-coordinate of reference starting point (rotation/scaling results)
15
14 13
12
11 10
09
08 07
06
05 04
03
02 01
00
BG2X_H
BG3X_H
02Ah
03Ah
0000h
W
Address
Register
AttributesInitial Value
15
14 13
12
11 10
09
08 07
06
05 04
03
02 01
00
BG2Y_L
BG3Y_L
02Ch
03Ch
0000h
W
Address
Register
Attributes Initial Value
15
14 13
12
11 10
09
08 07
06
05 04
03
02 01
00
BG2Y_H
BG3Y_H
02Eh
03Eh
0000h
W
Address
Register
AttributesInitial Value
Y-coordinate of reference starting point
(rotation/scaling results)
Y-coordinate of reference starting point (rotation/scaling results)
X-coordinate of reference starting point
(rotation/scaling results)
Registers for Setting the Direction Parameters of BG Data
15
14 13
12
11 10
09
08 07
06
05 04
03
02 01
00
BG2PA
BG3PA
020h
030h
0100h
W
Address
Register
Attributes Initial Value
dx: distance of movement in x direction along same line
15
14 13
12
11 10
09
08 07
06
05 04
03
02 01
00
BG2PB
BG3PB
022h
032h
0000h
W
Address
Register
dmx: distance of movement in x direction along next line
15
14 13
12
11 10
09
08 07
06
05 04
03
02 01
00
BG2PC
BG3PC
024h
034h
0000h
W
Address
Register
dy: distance of movement in y direction along same line
15
14 13
12
11 10
09
08 07
06
05 04
03
02 01
00
BG2PD
BG3PD
026h
036h
0100h
W
Address
Register
dmy: distance of movement in y direction along next line
Attributes Initial Value
Attributes Initial Value
Attributes Initial Value