mirror of
https://github.com/lscharen/iigs-game-engine.git
synced 2024-11-21 20:30:50 +00:00
Core updates for BG1 scanline support
This commit is contained in:
Lucas Scharenbroich
parent
d31bd30649
commit
065603a758
@ -307,6 +307,7 @@ _ApplyScanlineBG1YPos
|
||||
:shift_value equ tmp5
|
||||
|
||||
; Avoid local var collision
|
||||
:ptr2 equ tmp8
|
||||
:ytbl_idx_pos_x2 equ tmp10
|
||||
:virt_line_pos_x2 equ tmp11
|
||||
:total_left_x2 equ tmp12
|
||||
@ -317,7 +318,12 @@ _ApplyScanlineBG1YPos
|
||||
sta :ptr
|
||||
lda StartXMod164Tbl+2
|
||||
sta :ptr+2
|
||||
ora :ptr
|
||||
|
||||
lda BG1StartXMod164Tbl
|
||||
sta :ptr2
|
||||
lda BG1StartXMod164Tbl+2
|
||||
sta :ptr2+2
|
||||
ora :ptr2
|
||||
|
||||
lda BG1StartY
|
||||
jsr Mod208
|
||||
@ -379,30 +385,19 @@ _ApplyScanlineBG1YPos
|
||||
|
||||
:_ApplyConstBG1YPos
|
||||
|
||||
lda #164
|
||||
sec
|
||||
sbc :shift_value
|
||||
clc
|
||||
adc BG1StartXMod164
|
||||
cmp #164+1
|
||||
bcc *+5
|
||||
sbc #164
|
||||
lda #164
|
||||
sec
|
||||
sbc :shift_value
|
||||
clc
|
||||
adc BG1StartXMod164
|
||||
cmp #164+1
|
||||
bcc *+5
|
||||
sbc #164
|
||||
sta :shift_value ; Base shift value
|
||||
|
||||
; sec
|
||||
; sbc BG1StartXMod164
|
||||
; bpl *+6
|
||||
; clc
|
||||
; adc #164
|
||||
; cmp #164
|
||||
; bcc *+3
|
||||
; sbc #164
|
||||
|
||||
; clc
|
||||
; adc :shift_value
|
||||
sta :shift_value
|
||||
; cmp #160
|
||||
; beq *+4
|
||||
; brk $55
|
||||
cmp #165
|
||||
bcc *+4
|
||||
brk $04
|
||||
|
||||
phb ; Save the existing bank
|
||||
tsc
|
||||
@ -428,9 +423,9 @@ _ApplyScanlineBG1YPos
|
||||
tax
|
||||
|
||||
lda :ytbl_idx_x2 ; Read from this location in the BG1YTable
|
||||
clc
|
||||
CopyBG1YTableToBG1Addr3 :shift_value
|
||||
; jsr CopyBG1YTableToBG1Addr
|
||||
; clc
|
||||
; CopyBG1YTableToBG1Addr3 :shift_value
|
||||
CopyBG1YTableToBG1Addr4 :shift_value;blttmp
|
||||
|
||||
lda :virt_line_x2 ; advance to the virtual line after
|
||||
adc :draw_count_x2 ; filled in
|
||||
@ -704,8 +699,43 @@ x01 ldal BG1YTable+00,x
|
||||
sta: BG1_ADDR+$0000,y
|
||||
none <<<
|
||||
|
||||
; Copy routine to move BG1YTable entries into BG1_ADDR position with an additional
|
||||
; shift on every line form the user-provided BG1StartXMod164Tbl.
|
||||
;
|
||||
; A = index into the BG1YTable array (x2)
|
||||
; Y = starting line * $1000
|
||||
; X = number of lines (x2)
|
||||
;
|
||||
; ]1 = constant shift value
|
||||
; ]2 = temp storage space
|
||||
CopyBG1YTableToBG1Addr4 mac
|
||||
phy ; save the registers
|
||||
phx
|
||||
phb
|
||||
pha
|
||||
jsr _SetDataBank ; Set to toolbox data bank
|
||||
|
||||
clc
|
||||
lda 1,s ; virtual_index_x2
|
||||
adc BG1StartXMod164Tbl ; Get the starting address in the array for this chunk
|
||||
tay
|
||||
|
||||
lda BG1StartXMod164Tbl+1 ; Set the bank to the array location
|
||||
pha
|
||||
plb
|
||||
plb
|
||||
|
||||
pla ; POp back the original value
|
||||
ApplyBG1ModXToShift ]1;]2 ; Copy the array into direct page storage and apply the shift
|
||||
|
||||
plb ; Restore the code field bank
|
||||
plx ; x is used directly in this routine
|
||||
ply
|
||||
ApplyBG1ShiftToCode ]2
|
||||
<<<
|
||||
|
||||
; Unrolled copy routine to move BG1YTable entries into BG1_ADDR position with an additional
|
||||
; shifton every line. This has to be split into two
|
||||
; shift on every line. This has to be split into two
|
||||
;
|
||||
; A = index into the BG1YTable array (x2)
|
||||
; Y = starting line * $1000
|
||||
@ -855,3 +885,105 @@ ApplyBG1OffsetValues
|
||||
:do01 ldal BG1YCache+00
|
||||
sta: BG1_ADDR+$0000,y
|
||||
:none rts
|
||||
|
||||
; Apply the per-scanline shift from the BG1StartXMod164Tbl pointer. Save the relevant values to the
|
||||
; direct page since the array could be in any bank.
|
||||
;
|
||||
; This does bounds checking to make sure the shift value remains in the valid range
|
||||
;
|
||||
; ]1 = source array offset
|
||||
; ]2 = constant shift value
|
||||
; ]3 = destination address
|
||||
_BG1ShiftTemplate mac
|
||||
lda ]1,y ; Load the value from the array
|
||||
adc ]2 ; Add to the direct page shift_value
|
||||
cmp #165 ; If below this value, we're good
|
||||
bcc *+6
|
||||
sbc #164
|
||||
clc
|
||||
adcl BG1YTable+]1,x
|
||||
sta ]3+]1
|
||||
<<<
|
||||
|
||||
AToX mac
|
||||
tax
|
||||
brl ]1
|
||||
<<<
|
||||
|
||||
ApplyBG1ModXToShift mac
|
||||
jmp (agmxts_tbl,x)
|
||||
agmxts_tbl da none
|
||||
da do01,do02,do03,do04
|
||||
da do05,do06,do07,do08
|
||||
da do09,do10,do11,do12
|
||||
da do13,do14,do15,do16
|
||||
do16 AToX o16
|
||||
do15 AToX o15
|
||||
do14 AToX o14
|
||||
do13 AToX o13
|
||||
do12 AToX o12
|
||||
do11 AToX o11
|
||||
do10 AToX o10
|
||||
do09 AToX o09
|
||||
do08 AToX o08
|
||||
do07 AToX o07
|
||||
do06 AToX o06
|
||||
do05 AToX o05
|
||||
do04 AToX o04
|
||||
do03 AToX o03
|
||||
do02 AToX o02
|
||||
do01 AToX o01
|
||||
|
||||
o16 _BG1ShiftTemplate 30;]1;]2
|
||||
o15 _BG1ShiftTemplate 28;]1;]2
|
||||
o14 _BG1ShiftTemplate 26;]1;]2
|
||||
o13 _BG1ShiftTemplate 24;]1;]2
|
||||
o12 _BG1ShiftTemplate 22;]1;]2
|
||||
o11 _BG1ShiftTemplate 20;]1;]2
|
||||
o10 _BG1ShiftTemplate 18;]1;]2
|
||||
o09 _BG1ShiftTemplate 16;]1;]2
|
||||
o08 _BG1ShiftTemplate 14;]1;]2
|
||||
o07 _BG1ShiftTemplate 12;]1;]2
|
||||
o06 _BG1ShiftTemplate 10;]1;]2
|
||||
o05 _BG1ShiftTemplate 8;]1;]2
|
||||
o04 _BG1ShiftTemplate 6;]1;]2
|
||||
o03 _BG1ShiftTemplate 4;]1;]2
|
||||
o02 _BG1ShiftTemplate 2;]1;]2
|
||||
o01 _BG1ShiftTemplate 0;]1;]2
|
||||
none <<<
|
||||
|
||||
; After the values are saved, the data bank can be repointed at the current code bank and the values copied in
|
||||
; from the direct page
|
||||
;
|
||||
; ]1 = offset in temp buffer
|
||||
; ]2 = address of temp buffer
|
||||
; ]3 = 4k offset in code buffer
|
||||
_BG1ShiftToCodeTemplate mac
|
||||
lda ]2+]1
|
||||
sta: BG1_ADDR+]3,y
|
||||
<<<
|
||||
|
||||
ApplyBG1ShiftToCode mac
|
||||
jmp (abstc_tbl,x)
|
||||
abstc_tbl da none
|
||||
da do01,do02,do03,do04
|
||||
da do05,do06,do07,do08
|
||||
da do09,do10,do11,do12
|
||||
da do13,do14,do15,do16
|
||||
do16 _BG1ShiftToCodeTemplate 30;]1;$F000
|
||||
do15 _BG1ShiftToCodeTemplate 28;]1;$E000
|
||||
do14 _BG1ShiftToCodeTemplate 26;]1;$D000
|
||||
do13 _BG1ShiftToCodeTemplate 24;]1;$C000
|
||||
do12 _BG1ShiftToCodeTemplate 22;]1;$B000
|
||||
do11 _BG1ShiftToCodeTemplate 20;]1;$A000
|
||||
do10 _BG1ShiftToCodeTemplate 18;]1;$9000
|
||||
do09 _BG1ShiftToCodeTemplate 16;]1;$8000
|
||||
do08 _BG1ShiftToCodeTemplate 14;]1;$7000
|
||||
do07 _BG1ShiftToCodeTemplate 12;]1;$6000
|
||||
do06 _BG1ShiftToCodeTemplate 10;]1;$5000
|
||||
do05 _BG1ShiftToCodeTemplate 8;]1;$4000
|
||||
do04 _BG1ShiftToCodeTemplate 6;]1;$3000
|
||||
do03 _BG1ShiftToCodeTemplate 4;]1;$2000
|
||||
do02 _BG1ShiftToCodeTemplate 2;]1;$1000
|
||||
do01 _BG1ShiftToCodeTemplate 0;]1;$0000
|
||||
none <<<
|
||||
Loading…
Reference in New Issue
Block a user