mirror of
https://github.com/deater/dos33fsprogs.git
synced 2024-06-08 15:29:41 +00:00
1056 lines
16 KiB
ArmAsm
1056 lines
16 KiB
ArmAsm
SHIPY EQU $E4
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; FIXME, sort out available ZP page space
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TURNING EQU $60
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SCREEN_X EQU $61
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SCREEN_Y EQU $62
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ANGLE EQU $63
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HORIZ_SCALE_I EQU $64
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HORIZ_SCALE_F EQU $65
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FACTOR_I EQU $66
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FACTOR_F EQU $67
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DX_I EQU $68
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DX_F EQU $69
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SPACEX_I EQU $6A
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SPACEX_F EQU $6B
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CX_I EQU $6C
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CX_F EQU $6D
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DY_I EQU $6E
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DY_F EQU $6F
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SPACEY_I EQU $70
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SPACEY_F EQU $71
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CY_I EQU $72
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CY_F EQU $73
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TEMP_I EQU $74
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TEMP_F EQU $75
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DISTANCE_I EQU $76
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DISTANCE_F EQU $77
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SPACEZ_I EQU $78
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SPACEZ_F EQU $79
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DRAW_SPLASH EQU $7A
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SPEED EQU $7B
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SPLASH_COUNT EQU $7C
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OVER_WATER EQU $7D
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;===========
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; CONSTANTS
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;===========
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SHIPX EQU 15
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TILE_W EQU 64
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TILE_H EQU 64
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MAP_MASK EQU (TILE_W - 1)
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LOWRES_W EQU 40
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LOWRES_H EQU 40
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flying_start:
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;===================
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; Clear screen/pages
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;===================
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jsr clear_screens
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jsr set_gr_page0
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;===============
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; Init Variables
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;===============
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lda #20
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sta SHIPY
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lda #0
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sta TURNING
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sta ANGLE
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sta SPACEX_I
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sta SPACEY_I
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sta CX_I
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sta CX_F
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sta CY_I
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sta CY_F
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sta DRAW_SPLASH
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sta SPEED
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sta SPLASH_COUNT
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sta OVER_WATER
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lda #1
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sta ANGLE
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lda #4
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sta SPACEZ_I
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lda #$80
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sta SPACEZ_F
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flying_loop:
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lda SPLASH_COUNT
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beq flying_keyboard
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dec SPLASH_COUNT ; decrement splash count
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flying_keyboard:
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jsr get_key ; get keypress
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lda LASTKEY
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; cmp #('Q') ; if quit, then return
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; bne skipskip
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; rts
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;skipskip:
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cmp #('W')
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bne check_down
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;===========
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; UP PRESSED
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;===========
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lda SHIPY
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cmp #17
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bcc check_down ; bgt, if shipy>16
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dec SHIPY
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dec SHIPY ; move ship up
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inc SPACEZ_I ; incement height
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lda #0
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sta SPLASH_COUNT
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check_down:
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cmp #('S')
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bne check_left
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;=============
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; DOWN PRESSED
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;=============
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lda SHIPY
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cmp #28
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bcs splashy ; ble, if shipy < 28
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inc SHIPY
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inc SHIPY ; move ship down
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dec SPACEZ_I ; decrement height
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bcc check_left
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splashy:
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lda #10
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sta SPLASH_COUNT
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check_left:
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cmp #('A')
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bne check_right
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;=============
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; LEFT PRESSED
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;=============
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lda TURNING
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bmi turn_left
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beq turn_left
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lda #$0
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sta TURNING
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clv
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bvc check_right
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turn_left:
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lda #253 ; -3
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sta TURNING
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dec ANGLE
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check_right:
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cmp #('D')
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bne check_speedup
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;==============
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; RIGHT PRESSED
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;==============
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lda TURNING ;; FIXME: optimize me
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bpl turn_right
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lda #0
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sta TURNING
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clv
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bvc check_speedup
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turn_right:
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lda #3
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sta TURNING
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inc ANGLE
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check_speedup:
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cmp #('Z')
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bne check_speeddown
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;=========
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; SPEED UP
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;=========
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lda #$3
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cmp SPEED
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beq check_speeddown
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inc SPEED
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check_speeddown:
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cmp #('X')
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bne check_brake
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;===========
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; SPEED DOWN
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;===========
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lda SPEED
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beq check_brake
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dec SPEED
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check_brake:
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cmp #(' '+128)
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bne check_land
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;============
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; BRAKE
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;============
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lda #$0
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sta SPEED
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check_land:
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cmp #13
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bne check_help
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;=====
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; LAND
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;=====
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; finds value in space_x.i,space_y.i
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; returns color in A
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lda CX_I
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sta SPACEX_I
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lda CY_I
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sta SPACEY_I
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jsr lookup_map
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cmp #COLOR_BOTH_LIGHTGREEN
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bne must_land_on_grass
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landing_loop:
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jsr draw_background_mode7
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; Draw Shadow
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lda #>shadow_forward
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sta INH
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lda #<shadow_forward
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sta INL
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lda #(SHIPX+3)
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sta XPOS
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clc
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lda SPACEZ_I
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adc #31
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and #$fe ; make sure it's even
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sta YPOS
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jsr put_sprite
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lda #>ship_forward
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sta INH
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lda #<ship_forward
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sta INL
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lda #SHIPX
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sta XPOS
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lda SHIPY
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sta YPOS
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jsr put_sprite
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jsr page_flip
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dec SPACEZ_I
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bpl landing_loop
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rts ; finish flying
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must_land_on_grass:
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lda #10
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sta CH ; HTAB 11
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lda #21
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sta CV ; VTAB 22
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lda #>(grass_string)
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sta OUTH
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lda #<(grass_string)
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sta OUTL
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jsr print_both_pages ; "NEED TO LAND ON GRASS!"
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check_help:
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cmp #('H')
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bne check_done
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;=====
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; HELP
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;=====
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jsr print_help
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check_done:
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;================
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; Wrap the Angle
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;================
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lda ANGLE
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and #$f
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sta ANGLE
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;================
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; Handle Movement
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;================
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speed_move:
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ldx SPEED
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beq draw_background
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lda ANGLE ; dx.i=fixed_sin[(angle+4)&0xf].i; // cos()
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clc
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adc #4
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and #$f
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asl
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tay
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lda fixed_sin_scale,Y
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sta DX_I
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iny ; dx.f=fixed_sin[(angle+4)&0xf].f; // cos()
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lda fixed_sin_scale,Y
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sta DX_F
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lda ANGLE ; dy.i=fixed_sin[angle&0xf].i; // sin()
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and #$f
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asl
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tay
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lda fixed_sin_scale,Y
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sta DY_I
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iny ; dx.f=fixed_sin[angle&0xf].f; // sin()
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lda fixed_sin_scale,Y
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sta DY_F
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speed_loop:
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clc ; fixed_add(&cx,&dx,&cx);
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lda CX_F
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adc DX_F
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sta CX_F
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lda CX_I
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adc DX_I
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sta CX_I
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clc ; fixed_add(&cy,&dy,&cy);
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lda CY_F
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adc DY_F
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sta CY_F
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lda CY_I
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adc DY_I
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sta CY_I
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dex
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bne speed_loop
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;====================
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; Draw the background
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;====================
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draw_background:
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jsr draw_background_mode7
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; lda #1
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; sta OVER_WATER
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; Calculate whether to draw the splash
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lda #0 ; set splash drawing to 0
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sta DRAW_SPLASH
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lda SPEED ; if speed==0, no splash
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beq no_splash
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lda TURNING
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beq no_turning_splash
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lda SHIPY
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cmp #27
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bcc no_turning_splash ; blt if shipy<25 skip
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lda #1
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sta SPLASH_COUNT
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no_turning_splash:
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lda OVER_WATER ; no splash if over land
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beq no_splash
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lda SPLASH_COUNT ; no splash if splash_count expired
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beq no_splash
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lda #1
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sta DRAW_SPLASH
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no_splash:
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;==============
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; Draw the ship
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;==============
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clv
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lda TURNING
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beq draw_ship_forward
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bpl draw_ship_right
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bmi draw_ship_left ;; FIXME: optimize order
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draw_ship_forward:
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lda DRAW_SPLASH
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beq no_forward_splash
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; Draw Splash
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lda #>splash_forward
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sta INH
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lda #<splash_forward
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sta INL
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lda #(SHIPX+1)
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sta XPOS
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clc
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lda SHIPY
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adc #9
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and #$fe ; make sure it's even
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sta YPOS
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jsr put_sprite
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no_forward_splash:
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; Draw Shadow
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lda #>shadow_forward
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sta INH
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lda #<shadow_forward
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sta INL
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lda #(SHIPX+3)
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sta XPOS
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clc
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lda SPACEZ_I
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adc #31
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and #$fe ; make sure it's even
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sta YPOS
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jsr put_sprite
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lda #>ship_forward
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sta INH
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lda #<ship_forward
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sta INL
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bvc draw_ship
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draw_ship_right:
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lda DRAW_SPLASH
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beq no_right_splash
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; Draw Splash
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lda #>splash_right
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sta INH
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lda #<splash_right
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sta INL
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lda #(SHIPX+1)
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sta XPOS
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clc
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lda #36
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sta YPOS
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jsr put_sprite
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no_right_splash:
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; Draw Shadow
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lda #>shadow_right
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sta INH
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lda #<shadow_right
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sta INL
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lda #(SHIPX+3)
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sta XPOS
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clc
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lda SPACEZ_I
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adc #31
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and #$fe ; make sure it's even
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sta YPOS
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jsr put_sprite
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lda #>ship_right
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sta INH
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lda #<ship_right
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sta INL
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dec TURNING
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bvc draw_ship
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draw_ship_left:
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lda DRAW_SPLASH
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beq no_left_splash
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; Draw Splash
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lda #>splash_left
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sta INH
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lda #<splash_left
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sta INL
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lda #(SHIPX+1)
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sta XPOS
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clc
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lda #36
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sta YPOS
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jsr put_sprite
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no_left_splash:
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; Draw Shadow
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lda #>shadow_left
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sta INH
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lda #<shadow_left
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sta INL
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lda #(SHIPX+3)
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sta XPOS
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clc
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lda SPACEZ_I
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adc #31
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and #$fe ; make sure it's even
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sta YPOS
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jsr put_sprite
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lda #>ship_left
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sta INH
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lda #<ship_left
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sta INL
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inc TURNING
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draw_ship:
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lda #SHIPX
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sta XPOS
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lda SHIPY
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sta YPOS
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jsr put_sprite
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;==================
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; flip pages
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;==================
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jsr page_flip
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;==================
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; loop forever
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;==================
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jmp flying_loop
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;===========================
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; Draw the Mode7 Background
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;===========================
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draw_background_mode7:
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; Draw Sky
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lda #COLOR_BOTH_MEDIUMBLUE ; MEDIUMBLUE color
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sta COLOR
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lda #0
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sta OVER_WATER
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sky_loop: ; draw line across screen
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ldy #40 ; from y=0 to y=6
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sty V2
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ldy #0
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pha
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jsr hlin_double ; hlin y,V2 at A
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pla
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clc
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adc #2
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cmp #6
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bne sky_loop
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; Draw Horizon
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lda #COLOR_BOTH_GREY ; Horizon is Grey
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sta COLOR
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lda #6 ; draw single line at 6/7
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ldy #40
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sty V2 ; hlin Y,V2 at A
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ldy #0
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jsr hlin_double ; hlin 0,40 at 6
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; fixed_mul(&space_z,&BETA,&factor);
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lda SPACEZ_I
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sta NUM1H
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lda SPACEZ_F
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sta NUM1L
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lda #$ff ; BETA_I
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sta NUM2H
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lda #$80 ; BETA_F
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sta NUM2L
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;; TEST
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;; lda #$0
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;; sta NUM1H
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;; lda #$2
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;; sta NUM1L
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;; lda #$0
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;; sta NUM2H
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;; lda #$3
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;; sta NUM2L
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jsr multiply
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lda RESULT+2
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sta FACTOR_I
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lda RESULT+1
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sta FACTOR_F
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;; SPACEZ=78 * ff80 = FACTOR=66
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;; C
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;; GOOD 4 80 * ffffffff 80 = fffffffd c0
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;; BAD 4 80 * ffffffff 80 = 42 40
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lda #8
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sta SCREEN_Y
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screeny_loop:
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ldy #0
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jsr hlin_setup ; y-coord in a, x-coord in y
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; sets up GBASL/GBASH
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lda #0 ; horizontal_scale.i = 0
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sta HORIZ_SCALE_I
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;horizontal_scale.f=
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; horizontal_lookup[space_z.i&0xf][(screen_y-8)/2];
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lda SPACEZ_I
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and #$f
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asl
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asl
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asl
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asl
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sta TEMP_I
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sec
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lda SCREEN_Y
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sbc #8
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lsr
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clc
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adc TEMP_I
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tay
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lda horizontal_lookup,Y
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sta HORIZ_SCALE_F
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|
|
;; brk ASM, horiz_scale = 00:73
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|
|
; calculate the distance of the line we are drawing
|
|
; fixed_mul(&horizontal_scale,&scale,&distance);
|
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lda HORIZ_SCALE_I
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sta NUM1H
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lda HORIZ_SCALE_F
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sta NUM1L
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lda #$14 ; SCALE_I
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sta NUM2H
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lda #$00 ; SCALE_F
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sta NUM2L
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jsr multiply
|
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lda RESULT+2
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sta DISTANCE_I
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lda RESULT+1
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sta DISTANCE_F
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|
;; brk ASM, distance = 08:fc
|
|
|
|
; calculate the dx and dy of points in space when we step
|
|
; through all points on this line
|
|
|
|
lda ANGLE ; dx.i=fixed_sin[(angle+8)&0xf].i; // -sin()
|
|
clc
|
|
adc #8
|
|
and #$f
|
|
asl
|
|
tay
|
|
lda fixed_sin,Y
|
|
sta DX_I
|
|
iny ; dx.f=fixed_sin[(angle+8)&0xf].f; // -sin()
|
|
lda fixed_sin,Y
|
|
sta DX_F
|
|
|
|
; fixed_mul(&dx,&horizontal_scale,&dx);
|
|
lda HORIZ_SCALE_I
|
|
sta NUM1H
|
|
lda HORIZ_SCALE_F
|
|
sta NUM1L
|
|
lda DX_I
|
|
sta NUM2H
|
|
lda DX_F
|
|
sta NUM2L
|
|
jsr multiply
|
|
lda RESULT+2
|
|
sta DX_I
|
|
lda RESULT+1
|
|
sta DX_F
|
|
|
|
;; ANGLE
|
|
;; brk ASM, dx = 00:00
|
|
|
|
lda ANGLE ; dy.i=fixed_sin[(angle+4)&0xf].i; // cos()
|
|
clc
|
|
adc #4
|
|
and #$f
|
|
asl
|
|
tay
|
|
lda fixed_sin,Y
|
|
sta DY_I
|
|
iny ; dy.f=fixed_sin[(angle+4)&0xf].f; // cos()
|
|
lda fixed_sin,Y
|
|
sta DY_F
|
|
|
|
; fixed_mul(&dy,&horizontal_scale,&dy);
|
|
lda HORIZ_SCALE_I
|
|
sta NUM1H
|
|
lda HORIZ_SCALE_F
|
|
sta NUM1L
|
|
lda DY_I
|
|
sta NUM2H
|
|
lda DY_F
|
|
sta NUM2L
|
|
jsr multiply
|
|
lda RESULT+2
|
|
sta DY_I
|
|
lda RESULT+1
|
|
sta DY_F
|
|
|
|
;; brk ASM, dy = 00:73
|
|
|
|
; calculate the starting position
|
|
|
|
; fixed_add(&distance,&factor,&space_x);
|
|
clc ; fixed_add(&distance,&factor,&space_y);
|
|
lda DISTANCE_F
|
|
adc FACTOR_F
|
|
sta SPACEY_F
|
|
sta SPACEX_F
|
|
lda DISTANCE_I
|
|
adc FACTOR_I
|
|
sta SPACEY_I
|
|
sta SPACEX_I
|
|
|
|
;; brk space_x = 06:bc
|
|
|
|
lda ANGLE ; fixed_temp.i=fixed_sin[(angle+4)&0xf].i; // cos
|
|
clc
|
|
adc #4
|
|
and #$f
|
|
asl
|
|
tay
|
|
lda fixed_sin,Y
|
|
sta TEMP_I
|
|
iny ; fixed_temp.f=fixed_sin[(angle+4)&0xf].f; // cos
|
|
lda fixed_sin,Y
|
|
sta TEMP_F
|
|
|
|
; fixed_mul(&space_x,&fixed_temp,&space_x);
|
|
lda SPACEX_I
|
|
sta NUM1H
|
|
lda SPACEX_F
|
|
sta NUM1L
|
|
lda TEMP_I
|
|
sta NUM2H
|
|
lda TEMP_F
|
|
sta NUM2L
|
|
jsr multiply
|
|
lda RESULT+2
|
|
sta SPACEX_I
|
|
lda RESULT+1
|
|
sta SPACEX_F
|
|
|
|
|
|
clc ; fixed_add(&space_x,&cx,&space_x);
|
|
lda SPACEX_F
|
|
adc CX_F
|
|
sta SPACEX_F
|
|
lda SPACEX_I
|
|
adc CX_I
|
|
sta SPACEX_I
|
|
|
|
lda #$ec ; fixed_temp.i=0xec; // -20 (LOWRES_W/2)
|
|
sta TEMP_I
|
|
lda #0 ; fixed_temp.f=0;
|
|
sta TEMP_F
|
|
|
|
; fixed_mul(&fixed_temp,&dx,&fixed_temp);
|
|
lda TEMP_I
|
|
sta NUM1H
|
|
lda TEMP_F
|
|
sta NUM1L
|
|
lda DX_I
|
|
sta NUM2H
|
|
lda DX_F
|
|
sta NUM2L
|
|
jsr multiply
|
|
lda RESULT+2
|
|
sta TEMP_I
|
|
lda RESULT+1
|
|
sta TEMP_F
|
|
|
|
|
|
clc ; fixed_add(&space_x,&fixed_temp,&space_x);
|
|
lda SPACEX_F
|
|
adc TEMP_F
|
|
sta SPACEX_F
|
|
lda SPACEX_I
|
|
adc TEMP_I
|
|
sta SPACEX_I
|
|
|
|
;;brk ;; brk space_x = 06:bc
|
|
|
|
lda ANGLE ; fixed_temp.i=fixed_sin[angle&0xf].i;
|
|
and #$f
|
|
asl
|
|
tay
|
|
lda fixed_sin,Y
|
|
sta TEMP_I
|
|
iny ; fixed_temp.f=fixed_sin[angle&0xf].f;
|
|
lda fixed_sin,Y
|
|
sta TEMP_F
|
|
|
|
|
|
; fixed_mul(&space_y,&fixed_temp,&space_y);
|
|
lda SPACEY_I
|
|
sta NUM1H
|
|
lda SPACEY_F
|
|
sta NUM1L
|
|
lda TEMP_I
|
|
sta NUM2H
|
|
lda TEMP_F
|
|
sta NUM2L
|
|
jsr multiply
|
|
lda RESULT+2
|
|
sta SPACEY_I
|
|
lda RESULT+1
|
|
sta SPACEY_F
|
|
|
|
|
|
clc ; fixed_add(&space_y,&cy,&space_y);
|
|
lda SPACEY_F
|
|
adc CY_F
|
|
sta SPACEY_F
|
|
lda SPACEY_I
|
|
adc CY_I
|
|
sta SPACEY_I
|
|
|
|
lda #$ec ; fixed_temp.i=0xec; // -20 (LOWRES_W/2)
|
|
sta TEMP_I
|
|
lda #0 ; fixed_temp.f=0;
|
|
sta TEMP_F
|
|
|
|
; fixed_mul(&fixed_temp,&dy,&fixed_temp);
|
|
lda TEMP_I
|
|
sta NUM1H
|
|
lda TEMP_F
|
|
sta NUM1L
|
|
lda DY_I
|
|
sta NUM2H
|
|
lda DY_F
|
|
sta NUM2L
|
|
jsr multiply
|
|
lda RESULT+2
|
|
sta TEMP_I
|
|
lda RESULT+1
|
|
sta TEMP_F
|
|
|
|
|
|
clc ; fixed_add(&space_y,&fixed_temp,&space_y);
|
|
lda SPACEY_F
|
|
adc TEMP_F
|
|
sta SPACEY_F
|
|
lda SPACEY_I
|
|
adc TEMP_I
|
|
sta SPACEY_I
|
|
|
|
;;brk ;; brk space_y = f7:04
|
|
|
|
lda #0
|
|
sta SCREEN_X
|
|
screenx_loop:
|
|
|
|
jsr lookup_map ; get color in A
|
|
|
|
ldy #0
|
|
sta (GBASL),Y ; plot double height
|
|
inc GBASL ; point to next pixel
|
|
|
|
; Check if over water
|
|
cmp #$22 ; see if dark blue
|
|
bne not_watery
|
|
|
|
lda SCREEN_Y ; only check pixel in middle of screen
|
|
cmp #38
|
|
bne not_watery
|
|
|
|
lda SCREEN_X ; only check pixel in middle of screen
|
|
cmp #20
|
|
bne not_watery
|
|
|
|
lda #$1 ; set over water
|
|
sta OVER_WATER
|
|
|
|
not_watery:
|
|
; advance to the next position in space
|
|
|
|
clc ; fixed_add(&space_x,&dx,&space_x);
|
|
lda SPACEX_F
|
|
adc DX_F
|
|
sta SPACEX_F
|
|
lda SPACEX_I
|
|
adc DX_I
|
|
sta SPACEX_I
|
|
|
|
clc ; fixed_add(&space_y,&dy,&space_y);
|
|
lda SPACEY_F
|
|
adc DY_F
|
|
sta SPACEY_F
|
|
lda SPACEY_I
|
|
adc DY_I
|
|
sta SPACEY_I
|
|
|
|
|
|
|
|
inc SCREEN_X
|
|
lda SCREEN_X
|
|
cmp #40 ; LOWRES width
|
|
bne screenx_loop
|
|
|
|
|
|
lda SCREEN_Y
|
|
clc
|
|
adc #2
|
|
sta SCREEN_Y
|
|
cmp #40 ; LOWRES height
|
|
beq done_screeny
|
|
jmp screeny_loop
|
|
done_screeny:
|
|
rts
|
|
|
|
|
|
;====================
|
|
; lookup_map
|
|
;====================
|
|
; finds value in space_x.i,space_y.i
|
|
; returns color in A
|
|
lookup_map:
|
|
lda SPACEX_I
|
|
and #MAP_MASK
|
|
sta TEMPY
|
|
|
|
lda SPACEY_I
|
|
and #MAP_MASK ; wrap to 64x64 grid
|
|
|
|
|
|
asl
|
|
asl
|
|
asl ; multiply by 8
|
|
clc
|
|
adc TEMPY ; add in X value
|
|
; (use OR instead?)
|
|
|
|
ldy SPACEX_I
|
|
cpy #$8
|
|
beq ocean_color ; bgt
|
|
bcs ocean_color
|
|
ldy SPACEY_I
|
|
cpy #$8
|
|
beq ocean_color ; bgt
|
|
bcs ocean_color
|
|
|
|
tay
|
|
lda flying_map,Y ; load from array
|
|
|
|
rts
|
|
|
|
ocean_color:
|
|
and #$1f
|
|
tay
|
|
lda water_map,Y ; the color of the sea
|
|
|
|
rts
|
|
|
|
flying_map:
|
|
.byte $22,$ff,$ff,$ff, $ff,$ff,$ff,$22
|
|
.byte $dd,$cc,$cc,$88, $44,$44,$00,$dd
|
|
.byte $dd,$cc,$cc,$cc, $88,$44,$44,$dd
|
|
.byte $dd,$cc,$cc,$88, $44,$44,$44,$dd
|
|
.byte $dd,$cc,$99,$99, $88,$44,$44,$dd
|
|
.byte $dd,$cc,$99,$88, $44,$44,$44,$dd
|
|
.byte $dd,$cc,$99,$99, $11,$44,$44,$dd
|
|
.byte $22,$dd,$dd,$dd, $dd,$dd,$dd,$22
|
|
|
|
|
|
water_map:
|
|
.byte $22,$22,$22,$22, $22,$22,$22,$22
|
|
.byte $ee,$22,$22,$22, $22,$22,$22,$22
|
|
.byte $22,$22,$22,$22, $22,$22,$22,$22
|
|
.byte $22,$22,$22,$22, $ee,$22,$22,$22
|
|
|
|
.include "tfv_multiply.s"
|
|
|
|
|
|
; 8.8 fixed point
|
|
; should we store as two arrays, one I one F?
|
|
fixed_sin:
|
|
.byte $00,$00 ; 0.000000=00.00
|
|
.byte $00,$61 ; 0.382683=00.61
|
|
.byte $00,$b5 ; 0.707107=00.b5
|
|
.byte $00,$ec ; 0.923880=00.ec
|
|
.byte $01,$00 ; 1.000000=01.00
|
|
.byte $00,$ec ; 0.923880=00.ec
|
|
.byte $00,$b5 ; 0.707107=00.b5
|
|
.byte $00,$61 ; 0.382683=00.61
|
|
.byte $00,$00 ; 0.000000=00.00
|
|
.byte $ff,$9f ; -0.382683=ff.9f
|
|
.byte $ff,$4b ; -0.707107=ff.4b
|
|
.byte $ff,$14 ; -0.923880=ff.14
|
|
.byte $ff,$00 ; -1.000000=ff.00
|
|
.byte $ff,$14 ; -0.923880=ff.14
|
|
.byte $ff,$4b ; -0.707107=ff.4b
|
|
.byte $ff,$9f ; -0.382683=ff.9f
|
|
|
|
fixed_sin_scale:
|
|
.byte $00,$00
|
|
.byte $00,$0c
|
|
.byte $00,$16
|
|
.byte $00,$1d
|
|
.byte $00,$20
|
|
.byte $00,$1d
|
|
.byte $00,$16
|
|
.byte $00,$0c
|
|
.byte $00,$00
|
|
.byte $ff,$f4
|
|
.byte $ff,$ea
|
|
.byte $ff,$e3
|
|
.byte $ff,$e0
|
|
.byte $ff,$e3
|
|
.byte $ff,$ea
|
|
.byte $ff,$f4
|
|
|
|
horizontal_lookup:
|
|
.byte $0C,$0A,$09,$08,$07,$06,$05,$05,$04,$04,$04,$04,$03,$03,$03,$03
|
|
.byte $26,$20,$1B,$18,$15,$13,$11,$10,$0E,$0D,$0C,$0C,$0B,$0A,$0A,$09
|
|
.byte $40,$35,$2D,$28,$23,$20,$1D,$1A,$18,$16,$15,$14,$12,$11,$10,$10
|
|
.byte $59,$4A,$40,$38,$31,$2C,$28,$25,$22,$20,$1D,$1C,$1A,$18,$17,$16
|
|
.byte $73,$60,$52,$48,$40,$39,$34,$30,$2C,$29,$26,$24,$21,$20,$1E,$1C
|
|
.byte $8C,$75,$64,$58,$4E,$46,$40,$3A,$36,$32,$2E,$2C,$29,$27,$25,$23
|
|
.byte $A6,$8A,$76,$68,$5C,$53,$4B,$45,$40,$3B,$37,$34,$30,$2E,$2B,$29
|
|
|
|
grass_string:
|
|
.asciiz "NEED TO LAND ON GRASS!"
|