Get vertical rotation scaling going

This commit is contained in:
Lucas Scharenbroich 2022-07-22 16:00:41 -05:00
parent 18da2546bd
commit acf0276ff5

View File

@ -40,7 +40,7 @@ _ApplyBG1XPosAngle
pld
rts
_ApplyBG1YPosAngle
_ApplyBG1YPosAngle_Orig
:virt_line equ tmp0
:lines_left equ tmp1
:draw_count equ tmp2
@ -222,3 +222,231 @@ SaveBG1AngleValues
bra :x02
:do01 tax
bra :x01
; Modified version that copies all of the values to an intermediate buffer and then into the
; code field. Allows values to be transformed on the fly
TmpAngleTbl ds 416
_ApplyBG1YPosAngle
:virt_line equ tmp0
:lines_left equ tmp1
:draw_count equ tmp2
:ytbl_idx equ tmp3
:angle_tbl equ tmp4
:scale_ptr equ tmp5
:lines_left_x2 equ tmp7
:angle_ptr equ tmp8
sty :angle_tbl
lda BG1Scaling ; Set the scaling table
and #$0007
asl
tax
lda ScalingTables,x
sta :scale_ptr
lda #^ScalingTables
sta :scale_ptr+2
lda BG1StartYMod208
sta :ytbl_idx ; Start copying from the first entry in the table
lda StartYMod208 ; This is the base line of the virtual screen
sta :virt_line ; Keep track of it
lda ScreenHeight
sta :lines_left
asl
sta :lines_left_x2
; Copy out the y-values from the rotation table into a temporary buffer
lda :ytbl_idx
asl
clc
adc :angle_tbl
sta :angle_ptr
lda #^ANGLEBNK
sta :angle_ptr+2
phb
phk
plb
ldx #0
txy
:loop0
phy
lda [:scale_ptr],y
tay
lda [:angle_ptr],y
ply
sta TmpAngleTbl,x
sta TmpAngleTbl+2,x
sta TmpAngleTbl+4,x
sta TmpAngleTbl+6,x
iny
iny
txa
clc
adc #8
tax
cpx :lines_left_x2
bcc :loop0
plb
; Copy the rotation values into the code fields
phb
stz :ytbl_idx ; just copy from a fixed table
:loop
lda :virt_line
asl
tax
ldal BTableLow,x ; Get the address of the first code field line
tay
sep #$20
ldal BTableHigh,x
pha ; push the bank on the stack
plb
rep #$20
lda :virt_line
and #$000F
eor #$FFFF
inc
clc
adc #16
min :lines_left
sta :draw_count ; Do this many lines
asl
tax
; lda :ytbl_idx ; Read from this location (duplicate every 4 lines)
; lsr
; lsr
; asl
; clc
; adc :angle_tbl
; sec
; sbc #ANGLEBNK
; jsr CopyAngleYTableToBG1Addr ; or CopyBG1YTableToBG1Addr2
lda :ytbl_idx ; Read from this location (duplicate every 4 lines)
asl
jsr CopyAngleTmpTableToBG1Addr ; or CopyBG1YTableToBG1Addr2
lda :virt_line ; advance to the virtual line after the segment we just
clc ; filled in
adc :draw_count
sta :virt_line
lda :ytbl_idx ; advance the index into the YTable
adc :draw_count
sta :ytbl_idx
lda :lines_left ; subtract the number of lines we just completed
sec
sbc :draw_count
sta :lines_left
jne :loop
plb
rts
; Unrolled copy routine to move y_angle entries into BG1_ADDR position with an additional
; shift. This has to be split into two
;
; A = index into the temp array (x2)
; Y = starting line * $1000
; X = number of lines (x2)
CopyAngleTmpTableToBG1Addr
; tax
; ldal ANGLEBNK+XX,x
; sta BG1_ADDR+$F000,y
phx
pha
jsr SaveBG1AngleValues2
pla
plx ; x is used directly in this routine
jmp ApplyBG1OffsetValues
SaveBG1AngleValues2
jmp (:tbl,x)
:tbl da :none
da :do01,:do02,:do03,:do04
da :do05,:do06,:do07,:do08
da :do09,:do10,:do11,:do12
da :do13,:do14,:do15,:do16
:do15 tax
bra :x15
:do14 tax
bra :x14
:do13 tax
bra :x13
:do12 tax
bra :x12
:do11 tax
bra :x11
:do10 tax
bra :x10
:do09 tax
bra :x09
:do08 tax
bra :x08
:do16 tax
ldal TmpAngleTbl+30,x
stal BG1YCache+30
:x15 ldal TmpAngleTbl+28,x
stal BG1YCache+28
:x14 ldal TmpAngleTbl+26,x
stal BG1YCache+26
:x13 ldal TmpAngleTbl+24,x
stal BG1YCache+24
:x12 ldal TmpAngleTbl+22,x
stal BG1YCache+22
:x11 ldal TmpAngleTbl+20,x
stal BG1YCache+20
:x10 ldal TmpAngleTbl+18,x
stal BG1YCache+18
:x09 ldal TmpAngleTbl+16,x
stal BG1YCache+16
:x08 ldal TmpAngleTbl+14,x
stal BG1YCache+14
:x07 ldal TmpAngleTbl+12,x
stal BG1YCache+12
:x06 ldal TmpAngleTbl+10,x
stal BG1YCache+10
:x05 ldal TmpAngleTbl+08,x
stal BG1YCache+08
:x04 ldal TmpAngleTbl+06,x
stal BG1YCache+06
:x03 ldal TmpAngleTbl+04,x
stal BG1YCache+04
:x02 ldal TmpAngleTbl+02,x
stal BG1YCache+02
:x01 ldal TmpAngleTbl+00,x
stal BG1YCache+00
:none rts
:do07 tax
bra :x07
:do06 tax
bra :x06
:do05 tax
bra :x05
:do04 tax
bra :x04
:do03 tax
bra :x03
:do02 tax
bra :x02
:do01 tax
bra :x01