dos33fsprogs/mist/keyboard.s
Vince Weaver 51307a5f72 mist: hookup another step on way to rocket
also fix issue with clipping on pointer
2020-03-14 01:20:01 -04:00

271 lines
3.5 KiB
ArmAsm

;==============================
; Handle Keypress
;==============================
handle_keypress:
lda KEYPRESS
bmi keypress
jmp no_keypress
keypress:
and #$7f ; clear high bit
check_left:
cmp #'A'
beq left_pressed
cmp #8 ; left key
bne check_right
left_pressed:
dec CURSOR_X
jmp done_keypress
check_right:
cmp #'D'
beq right_pressed
cmp #$15 ; right key
bne check_up
right_pressed:
inc CURSOR_X
jmp done_keypress
check_up:
cmp #'W'
beq up_pressed
cmp #$0B ; up key
bne check_down
up_pressed:
dec CURSOR_Y
dec CURSOR_Y
jmp done_keypress
check_down:
cmp #'S'
beq down_pressed
cmp #$0A
bne check_return
down_pressed:
inc CURSOR_Y
inc CURSOR_Y
jmp done_keypress
check_return:
cmp #' '
beq return_pressed
cmp #13
bne done_keypress
return_pressed:
lda IN_SPECIAL
beq not_special_return
special_return:
jsr handle_special
; special case, don't make cursor visible
jmp no_keypress
not_special_return:
lda IN_RIGHT
beq not_right_return
right_return:
jsr turn_right
jmp no_keypress
not_right_return:
lda IN_LEFT
beq not_left_return
left_return:
jsr turn_left
jmp no_keypress
not_left_return:
jsr go_forward
jmp no_keypress
done_keypress:
lda #1 ; make cursor visible
sta CURSOR_VISIBLE
no_keypress:
bit KEYRESET
rts
;============================
; handle_special
;===========================
; set up jump table fakery
handle_special:
ldy #LOCATION_SPECIAL_FUNC+1
lda (LOCATION_STRUCT_L),Y
pha
dey
lda (LOCATION_STRUCT_L),Y
pha
rts
;=============================
; change direction
;=============================
change_direction:
; load background
lda DIRECTION
bpl no_split
; split text/graphics
bit TEXTGR
; also change sprite cutoff
ldx #40
stx psc_smc1+1
stx psc_smc2+1
jmp done_split
no_split:
bit FULLGR
; also change sprite cutoff
ldx #48
stx psc_smc1+1
stx psc_smc2+1
done_split:
and #$f ; mask off special flags
asl
clc
adc #LOCATION_NORTH_BG
tay
lda (LOCATION_STRUCT_L),Y
sta LZSA_SRC_LO
iny
lda (LOCATION_STRUCT_L),Y
sta LZSA_SRC_HI
lda #$c ; load to page $c00
jsr decompress_lzsa2_fast
rts
;=============================
; change location
;=============================
change_location:
; reset pointer to not visible, centered
lda #0
sta CURSOR_VISIBLE
lda #20
sta CURSOR_X
sta CURSOR_Y
lda LOCATION
asl
tay
lda locations,Y
sta LOCATION_STRUCT_L
lda locations+1,Y
sta LOCATION_STRUCT_H
jsr change_direction
rts
;==========================
; go forward
;===========================
go_forward:
; update new location
lda DIRECTION
and #$f
clc
adc #LOCATION_NORTH_EXIT
tay
lda (LOCATION_STRUCT_L),Y
cmp #$ff
beq cant_go_forward
sta LOCATION
; update new direction
lda DIRECTION
and #$f
clc
adc #LOCATION_NORTH_EXIT_DIR
tay
lda (LOCATION_STRUCT_L),Y
sta DIRECTION
jsr change_location
cant_go_forward:
rts
;==========================
; turn left
;===========================
turn_left:
lda DIRECTION
cmp #DIRECTION_N
beq go_west
cmp #DIRECTION_W
beq go_south
cmp #DIRECTION_S
beq go_east
bne go_north
;==========================
; turn right
;===========================
turn_right:
lda DIRECTION
cmp #DIRECTION_N
beq go_east
cmp #DIRECTION_E
beq go_south
cmp #DIRECTION_S
beq go_west
bne go_north
go_north:
lda #DIRECTION_N
jmp done_turning
go_east:
lda #DIRECTION_E
jmp done_turning
go_south:
lda #DIRECTION_S
jmp done_turning
go_west:
lda #DIRECTION_W
jmp done_turning
done_turning:
sta DIRECTION
jsr change_direction
rts