mode7: rasterbars: speed up by not drawing transparent

This commit is contained in:
Vince Weaver 2018-01-31 00:31:16 -05:00
parent 4f5f6d08d2
commit f57854e43a

View File

@ -80,21 +80,25 @@ init_rows:
ldy #(NUM_ROWS-1) ; 2
draw_rows_loop:
lda row_color,Y
sta COLOR
lda row_color,Y ; 5
beq draw_rows_skip ; skip if black ; 2nt/3
tya
pha
asl
sta COLOR ; 3
tya ; 2
pha ; 3
asl ; 2
ldy #39 ; 2
sty V2 ; 3
ldy #0 ; 2
jsr hlin_double ; hlin y,V2 at A ; 63+(X*16)
pla ; 4
tay
dey
bpl draw_rows_loop
tay ; 2
draw_rows_skip:
dey ; 2
bpl draw_rows_loop ; 2
;==================
@ -108,6 +112,9 @@ draw_rows_loop:
; delay?
;==================
lda #100
jsr WAIT
;==================
; update y pointer
@ -133,7 +140,7 @@ not_there:
;===================
; color in A
; Y=offset
; Y preserved
; Y incremented
; A, X trashed
set_row_color: