82 lines
1.8 KiB
NASM
82 lines
1.8 KiB
NASM
; -----------------------------------------------------------
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; title.asm - full-screen menu card: big RABBIT / SCOOTER
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; logo flanked by two hopping rabbits, the scooter waiting at
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; the bottom, blinking "fire = start game"
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; -----------------------------------------------------------
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title_init:
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lda #BLACK ; the menu plays on a black screen
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sta bg_top
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sta bg_bot
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jsr clear_screen
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+prbig 2, 8, RED, txt_rabbit, 6
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+prbig 8, 6, WHITE, txt_scooter, 7
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+prtext 18, 8, WHITE, txt_info, 23
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; decoration: white rabbits flank the logo (sprites 1-2,
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; double-sized), the red scooter waits at the bottom
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lda #RED
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sta SPR_COL
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lda #WHITE
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sta SPR_COL+1
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sta SPR_COL+2
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lda #SPRP_SCOOT
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sta SPRPTR
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lda #172 ; center lane position
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sta SPRPOS
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lda #210
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sta SPRPOS+1
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lda #30 ; left rabbit
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sta SPRPOS+2
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lda #66
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sta SPRPOS+3
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sta SPRPOS+5
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lda #34 ; right rabbit: x = 290, MSB below
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sta SPRPOS+4
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lda #%00000100
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sta SPR_MSBX
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lda #%00000110 ; both rabbits double-sized
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sta SPR_XEX
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sta SPR_YEX
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lda #%00000111
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sta SPR_EN
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+setupd title_update
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rts
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title_update:
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; hop the flanking rabbits through the big frames,
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; half a cycle apart
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lda framectr
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lsr
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lsr
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lsr
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and #3
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sta rtmp
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clc
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adc #SPRP_BIG
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sta SPRPTR+1
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lda rtmp
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clc
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adc #2
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and #3
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clc
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adc #SPRP_BIG
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sta SPRPTR+2
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; blink the start line
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lda framectr
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and #32
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bne tu_hide
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+prtext 15, 11, YELLOW, txt_press, 17
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jmp tu_start
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tu_hide:
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+prtext 15, 11, YELLOW, txt_blank, 17
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tu_start:
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jsr start_edge
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beq tu_done
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jmp play_init ; its rts returns to the main loop
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tu_done:
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rts
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