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Fix vertical offset bug; was using the TileStore lookup index, not the TileStore offset

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This commit is contained in:
Lucas Scharenbroich 2022-06-01 09:19:28 -05:00
parent cde517bcc9
commit b022162036
1 changed files with 25 additions and 18 deletions
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43
src/Sprite2.s
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@ -16,6 +16,17 @@ AreaIndex equ tmp7
SpriteBit equ tmp10 ; set the bit of the value that if the current sprite index
; VBuffOrigin equ tmp11
; Table of pre-multiplied vbuff strides
vbuff_mul
dw 0*VBUFF_STRIDE_BYTES
dw 1*VBUFF_STRIDE_BYTES
dw 2*VBUFF_STRIDE_BYTES
dw 3*VBUFF_STRIDE_BYTES
dw 4*VBUFF_STRIDE_BYTES
dw 5*VBUFF_STRIDE_BYTES
dw 6*VBUFF_STRIDE_BYTES
dw 7*VBUFF_STRIDE_BYTES
; Marks a sprite as dirty. The work here is mapping from local screen coordinates to the
; tile store indices. The first step is to adjust the sprite coordinates based on the current
; code field offsets and then cache variations of this value needed in the rest of the subroutine
@ -94,7 +105,7 @@ _CalcDirtySprite
txa ; Get the vertical offset in the VBUFF memory
asl
tax
ldal :vbuff_mul,x
ldal vbuff_mul,x
sta tmp0
; Add the horizontal position to the horizontal offset to find the first column in the
@ -104,23 +115,29 @@ _CalcDirtySprite
clc
lda _Sprites+SPRITE_CLIP_LEFT,y
adc StartXMod164
tax
pha
and #$FFFC
lsr ; Even numbers from [0, 160] (80 elements)
adc RowTop
sta _Sprites+TS_LOOKUP_INDEX,y ; This is the index into the TileStoreLookup table
; Create an offset value for loading the calculated VBUFF addresses within the core renderer
; Create an offset value for loading the calculated VBUFF addresses within the core renderer by
; subtracting the actual TileStore offset from the sprite's vbuff address array
eor #$FFFF
tax
lda _Sprites+VBUFF_ARRAY_ADDR,y
sec
adc _Sprites+VBUFF_ARRAY_ADDR,y
sbc TileStoreLookup,x
; eor #$FFFF
; sec
; adc _Sprites+VBUFF_ARRAY_ADDR,y
sta tmp1 ; Spill this value to direct page temp space
; Calculate the final address of the sprite data in the stamp buffer. We have to move earlier
; in the buffer based on the horizontal offset and move up for each vertical offset.
txa
pla
and #$0003
tax
clc
@ -167,23 +184,13 @@ _MarkDirtySpriteTiles
clc
ldx _Sprites+TS_COVERAGE_SIZE,y
jmp (:mark,x)
jmp (mdsmark,x)
:mark dw :mark1x1,:mark1x2,:mark1x3,mdsOut
mdsmark dw :mark1x1,:mark1x2,:mark1x3,mdsOut
dw :mark2x1,:mark2x2,:mark2x3,mdsOut
dw :mark3x1,:mark3x2,:mark3x3,mdsOut
dw mdsOut,mdsOut,mdsOut,mdsOut
:vbuff_mul
dw 0*VBUFF_STRIDE_BYTES
dw 1*VBUFF_STRIDE_BYTES
dw 2*VBUFF_STRIDE_BYTES
dw 3*VBUFF_STRIDE_BYTES
dw 4*VBUFF_STRIDE_BYTES
dw 5*VBUFF_STRIDE_BYTES
dw 6*VBUFF_STRIDE_BYTES
dw 7*VBUFF_STRIDE_BYTES
; Pair of macros to make the unrolled loop more concise
;
; 1. Load the tile store address from a fixed offset