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Removed 1 instruction from draw_line_down.s 6% performance boost

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hugova 2025-03-24 18:25:42 +01:00
parent 3ce76c02a8
commit 9b8e3fe33f
1 changed files with 3 additions and 4 deletions
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7
wip-hugo/routines/line/line_down.s
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@ -52,6 +52,7 @@
jsr pixel_draw ;;only used first pixel. after this relative position is abused
LDY #$00
LDX X_pos
for_x:
;; Paints A to address i btp_mem_pos* + Y
;; Y is our Y-pos-chunk-offset.
@ -68,8 +69,7 @@ move_8px_left:
LDA #%10000000
STA byte_to_paint
increment_pixel_x_end:
INC X_pos;; legacy
LDX X_pos
INX
CPX X_end
BEQ end
;;If D < %00000010 00000000: case_2
@ -78,14 +78,13 @@ increment_pixel_x_end:
case_1:; C =1 so we can use !
Sub_16 >D, <D, >V, <V, ! ; D = D - V
increment_y_pos:
;Add_16 >btp_mem_pos, <btp_mem_pos, #$01, #$00
INY
CPY #$08 ;
BNE for_x
move_8px_down: ; Z=1 --> C=1
;; +320-8 bytes
LDY #$00
Add_16 >btp_mem_pos, <btp_mem_pos,#$40, #$01
Add_16 >btp_mem_pos, <btp_mem_pos, #$40, #$01
jmp for_x
increment_y_pos_end:
case_2: ;; C =0 because LAG_16 so we can use !