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Fix register assignments for dynamic tile renderer

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Lucas Scharenbroich 2021-11-13 19:44:30 -06:00
parent 596777da8d
commit b87e2a8d33
1 changed files with 17 additions and 18 deletions
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35
src/blitter/Tiles00010.s
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@ -2,14 +2,16 @@
;
; These tile renderes are for "normal" tiles that also apply their mask data. If the case of the second
; background being disabled, the optimized variants are the same as Tile00000
_TBMaskedTile dw _TBMaskedTile_00,_TBMaskedTile_0H,_TBMaskedTile_V0,_TBMaskedTile_VH
dw _TBCopyData,_TBCopyDataH,_TBCopyDataV,_TBCopyDataVH
;
; Y register = address of code field tile
; X register = tile address
; Accumulator = logical word offset of the tile (0, 2, 4, ..., 82)
;
; Need to slightly remap these register inputs to save into the direct page cached values
_TBMaskedTile_00
stx _X_REG ; Save these values as we will need to reload them
sta _X_REG ; Save these values as we will need to reload them
sty _Y_REG ; at certain points
sta _T_PTR
tax
stx _T_PTR
; Do the left column first
@ -43,10 +45,9 @@ _TBMaskedTile_00
rts
_TBMaskedTile_0H
stx _X_REG ; Save these values as we will need to reload them
sty _Y_REG ; at certain points
sta _T_PTR
tax
sta _X_REG
sty _Y_REG
stx _T_PTR
CopyMaskedWord tiledata+64+0;tiledata+64+32+0;$0003
CopyMaskedWord tiledata+64+4;tiledata+64+32+4;$1003
@ -72,10 +73,9 @@ _TBMaskedTile_0H
rts
_TBMaskedTile_V0
stx _X_REG ; Save these values as we will need to reload them
sty _Y_REG ; at certain points
sta _T_PTR
tax
sta _X_REG
sty _Y_REG
stx _T_PTR
CopyMaskedWord tiledata+0;tiledata+32+0;$7003
CopyMaskedWord tiledata+4;tiledata+32+4;$6003
@ -101,10 +101,9 @@ _TBMaskedTile_V0
rts
_TBMaskedTile_VH
stx _X_REG ; Save these values as we will need to reload them
sty _Y_REG ; at certain points
sta _T_PTR
tax
sta _X_REG
sty _Y_REG
stx _T_PTR
CopyMaskedWord tiledata+64+0;tiledata+64+32+0;$7003
CopyMaskedWord tiledata+64+4;tiledata+64+32+4;$6003