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0x212A - WBGLOG (BGウインドウマスクロジック設定)

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D7	D6	D5	D4	D3	D2	D1	D0
4	4	3	3	2	2	1	1

0x212B - WOBJLOG (スプライトウインドウマスクロジック設定)

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D7	D6	D5	D4	D3	D2	D1	D0
-	-	-	-	c	c	o	o

• 44/33/22/11/oo/cc : マスクロジック (BG1/BG2/BG3/BG4/OBJ/Color) ウインドウの組み合わせロジックをブールで指定する。 00 = OR 01 = AND 10 = XOR 11 = XNOR

Consider two variables, W1 and W2, which are true for pixels between the appropriate left and right bounds as set in $2126-$2129 and false otherwise. Then, you have the following possibilities: (replace "W#" with "~W#", depending on the Inversion settings of $2123-$2125) Neither window enabled => nothing masked. One window enabled => Either W1 or W2, as appropriate. Both windows enabled => W1 op W2, where "op" is as above. Where the function is true, the BG will be masked.

See the section "WINDOWS" below for more details.