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cc65/libsrc/c64/mouse.s
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which included commits to RCS files with non-trunk default branches.


git-svn-id: svn://svn.cc65.org/cc65/trunk@3 b7a2c559-68d2-44c3-8de9-860c34a00d81
2000-05-28 13:40:48 +00:00

385 lines
7.3 KiB
ArmAsm

;
; Ullrich von Bassewitz, 24.04.1999
;
; Routines for the 1351 proportional mouse. Parts of the code are from
; the Commodore 1351 mouse users guide.
;
.export _mouse_init, _mouse_done
.export _mouse_hide, _mouse_show
.export _mouse_box, _mouse_info
.export _mouse_move
.import popa, popsreg, addysp1
.importzp sp, sreg
.include "c64.inc"
.code
; --------------------------------------------------------------------------
;
; void __fastcall__ mouse_init (unsigned char port, unsigned char sprite);
;
_mouse_init:
tax ; Save sprite number
jsr popa ; Get the port number
ldy OldIRQ+1 ; Already initialized?
bne Done ; Jump if yes
stx MouseSprite ; Remember the sprite number
sta MousePort ; Remember the port number
; Initialize variables
ldx #0
stx XPos
stx XPos+1
stx YPos
stx YPos+1
stx OldPotX
stx OldPotY
stx XMin
stx XMin+1
stx YMin
stx YMin+1
stx YMax+1
inx ; X = 1
stx Visible ; Mouse *not* visible
stx XMax+1 ; >320
ldx #<320
stx XMax
ldx #200
stx YMax
; Remember the old IRQ vector
lda IRQVec
sta OldIRQ
lda IRQVec+1
sta OldIRQ+1
; Set our own IRQ vector
lda #<MouseIRQ
ldx #>MouseIRQ
bne SetIRQ
; --------------------------------------------------------------------------
;
; void mouse_done (void);
;
_mouse_done:
lda OldIRQ ; Initialized?
ldx OldIRQ+1
beq Done ; Jump if no
ldy #0
sty OldIRQ+1 ; Reset the initialized flag
SetIRQ: sei ; Disable interrupts
sta IRQVec ; Set the new/old vector
stx IRQVec+1
cli ; Enable interrupts
Done: rts
; --------------------------------------------------------------------------
;
; void mouse_hide (void);
;
_mouse_hide:
lda Visible ; Get the flag
bne @L1 ; Jump if already invisible
ldx MouseSprite ; Sprite defined?
beq @L1 ; Jump if no
lda BitMask-1,x ; Get bit mask
eor #$FF ; We must clear the bit
sei ; Disable interrupts
and VIC_SPR_ENA
sta VIC_SPR_ENA ; Disable sprite
cli ; Enable interrupts
@L1: inc Visible ; Set the flag to invisible
rts
; --------------------------------------------------------------------------
;
; void mouse_show (void);
;
_mouse_show:
dec Visible ; Get the flag
bne @L1 ; Jump if still invisible
ldx MouseSprite ; Sprite defined?
beq @L1 ; Jump if no
lda BitMask-1,x ; Get bit mask
sei ; Disable interrupts
ora VIC_SPR_ENA
sta VIC_SPR_ENA ; Enable sprite
cli ; Enable interrupts
@L1: rts
; --------------------------------------------------------------------------
;
; void __fastcall__ mouse_box (int minx, int miny, int maxx, int maxy);
;
_mouse_box:
sei ; Disable interrupts
sta YMax
stx YMax+1 ; maxy
ldy #0
lda (sp),y
sta XMax
iny
lda (sp),y
sta XMax+1 ; maxx
iny
lda (sp),y
sta YMin
iny
lda (sp),y
sta YMin+1 ; miny
iny
lda (sp),y
sta XMin
iny
lda (sp),y
sta XMin+1 ; minx
cli ; Enable interrupts
jmp addysp1 ; Drop params, return
; --------------------------------------------------------------------------
;
; void mouse_info (...);
;
_mouse_info:
rts
; --------------------------------------------------------------------------
;
; void __fastcall__ mouse_move (int x, int y);
;
_mouse_move:
jsr popsreg ; Get X
sei ; Disable interrupts
sta YPos
stx YPos+1
lda sreg
ldx sreg+1
sta XPos
stx XPos+1 ; Set new position
lda Visible ; Mouse visible?
bne @L9 ; Jump if no
lda MouseSprite ; Sprite defined?
beq @L9
jsr MoveSprite ; Move the sprite to the mouse pos
@L9: cli ; Enable interrupts
rts
; --------------------------------------------------------------------------
;
; Mouse interrupt handler
;
MouseIRQ:
cld
lda SID_ADConv1 ; Get mouse X movement
ldy OldPotX
jsr MoveCheck ; Calculate movement vector
sty OldPotX
; Calculate the new X coordinate (--> a/y)
clc
adc XPos
tay ; Remember low byte
txa
adc XPos+1
; Limit the X coordinate to the bounding box
cpy XMin+1
bne @L1
cmp XMin
@L1: bpl @L2
ldy XMin
lda XMin+1
jmp @L4
@L2: cpy XMax+1
bne @L3
cmp XMax
beq @L4
@L3: bmi @L4
ldy XMax
lda XMax+1
@L4: sty XPos
sta XPos+1
; Calculate the Y movement vector
lda SID_ADConv2 ; Get mouse Y movement
ldy OldPotY
jsr MoveCheck ; Calculate movement
sty OldPotY
; Calculate the new Y coordinate (--> a/y)
clc
adc YPos
tay ; Remember low byte
txa
adc YPos+1
; Limit the Y coordinate to the bounding box
cpy YMin+1
bne @L5
cmp YMin
@L5: bpl @L6
ldy YMin
lda YMin+1
jmp @L8
@L6: cpy YMax+1
bne @L7
cmp YMax
beq @L8
@L7: bmi @L8
ldy YMax
lda YMax+1
@L8: sty YPos
sta YPos+1
; Jump to the next IRQ handler
jmp (OldIRQ)
; --------------------------------------------------------------------------
;
; Move check routine, called for both coordinates.
;
; Entry: y = old value of pot register
; a = current value of pot register
; Exit: y = value to use for old value
; x/a = delta value for position
;
MoveCheck:
sty OldValue
sta NewValue
ldx #$00
sec ; a = mod64 (new - old)
sbc OldValue
and #%01111111
cmp #%01000000 ; if (a > 0)
bcs @L1 ;
lsr a ; a /= 2;
beq @L2 ; if (a != 0)
ldy NewValue ; y = NewValue
rts ; return
@L1: ora #%11000000 ; else or in high order bits
cmp #$FF ; if (a != -1)
beq @L2
sec
ror a ; a /= 2
ldx #$FF ; high byte = -1
ldy NewValue
rts
@L2: lda #0
rts
; --------------------------------------------------------------------------
;
; Move the mouse sprite to the current mouse position. Must be called
; with interrupts off.
;
MoveSprite:
lda Visible ; Mouse pointer visible?
bne @L9 ; Jump if no
ldx MouseSprite ; Sprite defined?
beq @L9 ; Jump if no
ldy BitMask-1,x ; Get high bit mask
txa
asl a ; Index*2
tax
; Set the X position
lda XPos+1 ; Negative?
bmi @L2 ; Jump if yes
beq @L1
tya ; Load high position bit
@L1: ora VIC_SPR_HI_X ; Set high bit
sta VIC_SPR_HI_X
lda XPos
sta VIC_SPR0_X,x ; Set low byte
; Set the Y position
@L2: ldy YPos+1 ; Negative or too large?
bne @L9 ; Jump if yes
lda YPos
sta VIC_SPR0_Y,x ; Set Y position
; Done
@L9: rts
; --------------------------------------------------------------------------
; Data
.bss
OldIRQ: .res 2 ; Old IRQ vector
MousePort: .res 1 ; Port used for the mouse
MouseSprite: .res 1 ; Number of sprite to control
OldValue: .res 1 ; Temp for MoveCheck routine
NewValue: .res 1 ; Temp for MoveCheck routine
Visible: .res 1 ; Is the mouse visible?
OldPotX: .res 1 ; Old hw counter values
OldPotY: .res 1
XPos: .res 2 ; Current mouse position, X
YPos: .res 2 ; Current mouse position, Y
XMin: .res 2 ; X1 value of bounding box
YMin: .res 2 ; Y1 value of bounding box
XMax: .res 2 ; X2 value of bounding box
YMax: .res 2 ; Y2 value of bounding box
.data
BitMask: .byte $01, $02, $04, $08, $10, $20, $40, $80