dos33fsprogs/games/keen/keyboard.s

354 lines
4.9 KiB
ArmAsm

JUMP_HEIGHT = 8
;==============================
; Handle Keypress
;==============================
handle_keypress:
; first handle joystick
lda JOYSTICK_ENABLED
beq actually_handle_keypress
; only check joystick every-other frame
lda FRAMEL
and #$1
beq actually_handle_keypress
check_button:
lda PADDLE_BUTTON0
bpl button_clear
lda JS_BUTTON_STATE
bne js_check
lda #1
sta JS_BUTTON_STATE
lda #' '
jmp check_sound
button_clear:
lda #0
sta JS_BUTTON_STATE
js_check:
jsr handle_joystick
js_check_left:
lda value0
cmp #$20
bcs js_check_right ; if less than 32, left
lda #'A'
bne check_sound
js_check_right:
cmp #$40
bcc js_check_up
lda #'D'
bne check_sound
js_check_up:
lda value1
cmp #$20
bcs js_check_down
lda #'W'
bne check_sound
js_check_down:
cmp #$40
bcc done_joystick
lda #'S'
bne check_sound
done_joystick:
actually_handle_keypress:
lda KEYPRESS
bmi keypress
jmp no_keypress
keypress:
and #$7f ; clear high bit
cmp #' '
beq check_sound ; make sure not to lose space
and #$df ; convert uppercase to lower case
check_sound:
cmp #$14 ; control-T
bne check_help
lda SOUND_STATUS
eor #SOUND_DISABLED
sta SOUND_STATUS
jmp done_keypress
check_help:
cmp #'H' ; H (^H is same as left)
bne check_joystick
jsr print_help
jmp done_keypress
; can't be ^J as that's the same as down
check_joystick:
cmp #'J' ; J
bne check_left
lda JOYSTICK_ENABLED
eor #1
sta JOYSTICK_ENABLED
jmp done_keypress
check_left:
cmp #'A'
beq left_pressed
cmp #8 ; left key
bne check_right
left_pressed:
;===============================
; left pressed
; if facing left, walk left
; if facing right and walking, stop
; if facing right and not walking, face left
lda KEEN_DIRECTION
cmp #$ff ; check if facing left
bne left_facing_right
lda #4
sta KEEN_WALKING
jmp done_left_pressed
left_facing_right:
lda KEEN_WALKING
beq left_not_walking
lda #0
sta KEEN_WALKING
beq done_left_pressed ; bra
left_not_walking:
lda #$ff
sta KEEN_DIRECTION
done_left_pressed:
jmp done_keypress
check_right:
cmp #'D'
beq right_pressed
cmp #$15 ; right key
bne check_jump_right
;===============================
; right pressed
; if facing right, walk right
; if facing left and walking, stop
; if facing left and not walking, face right
right_pressed:
lda KEEN_DIRECTION
cmp #$1 ; check if facing right
bne right_facing_left
lda #4
sta KEEN_WALKING
jmp done_left_pressed
right_facing_left:
lda KEEN_WALKING
beq right_not_walking
lda #0
sta KEEN_WALKING
beq done_right_pressed ; bra
right_not_walking:
lda #$1
sta KEEN_DIRECTION
done_right_pressed:
jmp done_keypress
check_jump_right:
cmp #'E'
bne check_jump_left
jump_right:
; jump
lda KEEN_JUMPING
bne done_right_pressed ; don't jump if already jumping
lda KEEN_FALLING
bne done_right_pressed ; don't jump if falling
lda #JUMP_HEIGHT
sta KEEN_JUMPING
; jsr jump_noise
lda #1
sta KEEN_DIRECTION
lda #10
sta KEEN_WALKING
jmp done_keypress
check_jump_left:
cmp #'Q'
bne check_up
jump_left:
; jump
lda KEEN_JUMPING
bne done_right_pressed ; don't jump if already jumping
lda KEEN_FALLING
bne done_right_pressed ; don't jump if falling
lda #JUMP_HEIGHT
sta KEEN_JUMPING
; jsr jump_noise
lda #$FF
sta KEEN_DIRECTION
lda #10
sta KEEN_WALKING
jmp done_keypress
check_up:
cmp #'W'
beq up_pressed
cmp #$0B ; up key
bne check_down
up_pressed:
; jsr up_action
done_up_pressed:
jmp done_keypress
check_down:
cmp #'S'
beq down_pressed
cmp #$0A
bne check_space
down_pressed:
done_down_pressed:
jmp done_keypress
check_space:
cmp #' '
bne check_comma
space_pressed:
; jump
lda KEEN_JUMPING
bne done_keypress ; don't jump if already jumping
lda KEEN_FALLING
bne done_keypress ; don't jump if falling
lda #JUMP_HEIGHT
sta KEEN_JUMPING
; jsr jump_noise
jmp done_keypress
check_comma:
cmp #'M'
bne check_return
comma_pressed:
; check if we have any shots left
lda RAYGUNS
beq done_comma
; use up a shot
dec RAYGUNS
; shoot
lda LASER_OUT
bne done_comma
ldy #SFX_GUNCLICK
jsr play_sfx
; jsr laser_noise
lda KEEN_DIRECTION
sta LASER_DIRECTION
lda #2
sta KEEN_SHOOTING
cmp #1
beq laser_right
laser_left:
lda KEEN_X
sec
sbc #1
jmp laser_assign
laser_right:
lda KEEN_X
clc
adc #2
laser_assign:
sta LASER_X
lda KEEN_Y
clc
adc #4
sta LASER_Y
inc LASER_OUT
done_comma:
jmp no_keypress
check_return:
cmp #13
bne check_escape
return_pressed:
jsr draw_status_bar
done_return:
jmp no_keypress
check_escape:
cmp #27
bne done_keypress
jsr print_quit
jmp done_keypress
done_keypress:
no_keypress:
bit KEYRESET
rts