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Reduses one CMP instruction in line_up_inv

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hugova 2025-07-17 13:53:56 +02:00
parent f64d28168b
commit cda44f292c
1 changed files with 4 additions and 3 deletions
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7
wip-hugo/routines/line/line_up_inv.s
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@ -52,6 +52,8 @@ selfmod:
end_selfmod: end_selfmod:
JSR pixel_calc ;;only used first pixel. after this relative position is abused JSR pixel_calc ;;only used first pixel. after this relative position is abused
STA byte_to_paint STA byte_to_paint
INY
Sub_16 btp_mem_pos, btp_mem_pos + 1, #$01, #$00 ;; Y has always a offset of at least 1
;LDY #$00 ;LDY #$00
LDX dy LDX dy
for_y: for_y:
@ -60,11 +62,10 @@ for_y:
STA (btp_mem_pos), Y STA (btp_mem_pos), Y
decrement_y_pos: decrement_y_pos:
DEY DEY
CPY #$ff
BNE decrement_y_pos_end BNE decrement_y_pos_end
move_8px_up: move_8px_up:
LDY #$07 LDY #$08
Sub_16 btp_mem_pos, btp_mem_pos + 1,#$40 , #$01, ! Sub_16 btp_mem_pos, btp_mem_pos + 1,#$3F , #$01, !
decrement_y_pos_end: decrement_y_pos_end:
DEX DEX
BEQ end BEQ end