.export _mouse_box, _mouse_info
.export _mouse_move, _mouse_pos
.export _mouse_buttons, _mouse_info
+ .condes MouseIRQ, 2
.import _readjoy
- .import popa, popax, addysp1
- .importzp ptr1, sp, sreg
+ .import popax, addysp1
+ .importzp ptr1, sp
.include "c128.inc"
; --------------------------------------------------------------------------
;
-; unsigned char __fastcall__ mouse_init (unsigned char port,
-; unsigned char type);
+; unsigned char __fastcall__ mouse_init (unsigned char type);
;
-_mouse_init:
- jsr popa ; Ignore type and port
-
- ldy OldIRQ+1 ; Already initialized?
+.proc _mouse_init
+ lda Initialized ; Already initialized?
bne AlreadyInitialized ; Jump if yes
; Initialize variables
sta XMax
stx XMax+1 ; XMax = 320 + sprite width
-; Remember the old IRQ vector
+; Save the old init status and reset bit 0. This will disable the BASIC
+; IRQ handler which will otherwise try to manage the mouse sprite on its
+; own
- lda IRQVec
- sta OldIRQ
- lda IRQVec+1
- sta OldIRQ+1
+ lda INIT_STATUS
+ sta OldInitStatus
+ and #$FE
+ sta INIT_STATUS
-; Set our own IRQ vector. We cheat here to save a few bytes of code:
-; The function is expected to return a value not equal to zero on success,
-; and since we know that the high byte of the IRQ handler address is never
-; zero, we will return just this byte.
+; Mouse successfully initialized
- ldx #<MouseIRQ
- lda #>MouseIRQ
- bne SetIRQ ; Branch always
+ lda #1
+ sta Initialized
+ rts
AlreadyInitialized:
- lda #0 ; Error
+ lda #0 ; Error
rts
+.endproc
+
; --------------------------------------------------------------------------
;
; void mouse_done (void);
;
_mouse_done:
- ldx OldIRQ ; Initialized?
- lda OldIRQ+1
- beq Done ; Jump if no
- ldy #0
- sty OldIRQ+1 ; Reset the initialized flag
-SetIRQ: sei ; Disable interrupts
- stx IRQVec ; Set the new/old vector
- sta IRQVec+1
- cli ; Enable interrupts
-Done: rts
+ lda Initialized ; Initialized?
+ beq mddone ; Jump if no
+ lda #0
+ sta Initialized ; Reset the initialized flag
+ lda OldInitStatus ; Load the old BASIC int bit
+ and #$01 ; Mask it
+ ora INIT_STATUS ; Restore the old state
+ sta INIT_STATUS
+
+; Disable the mouse sprite
+
+DisableSprite:
+ lda #$FE ; Clear bit for sprite #0
+ sei ; Disable interrupts
+ and VIC_SPR_ENA
+ sta VIC_SPR_ENA ; Disable sprite
+ cli ; Enable interrupts
+mddone: rts
+
; --------------------------------------------------------------------------
;
; void mouse_hide (void);
;
-_mouse_hide:
+.proc _mouse_hide
+
lda Invisible ; Get the flag
bne @L1 ; Jump if already invisible
-
- lda #$FE ; Clear bit for sprite #0
- sei ; Disable interrupts
- and VIC_SPR_ENA
- sta VIC_SPR_ENA ; Disable sprite
- cli ; Enable interrupts
-
+ jsr DisableSprite ; Disable the mouse sprite
@L1: inc Invisible ; Set the flag to invisible
rts
+.endproc
+
; --------------------------------------------------------------------------
;
; void mouse_show (void);
;
-_mouse_show:
+.proc _mouse_show
+
lda Invisible ; Mouse invisible?
beq @L1 ; Jump if no
dec Invisible ; Set the flag
lda VIC_SPR_ENA ; Get sprite enable register
ora #$01 ; Enable sprite #0
sta VIC_SPR_ENA ; Write back
- cli ; Enable interrupts
+ cli ; Enable interrupts
@L1: rts
+.endproc
+
; --------------------------------------------------------------------------
;
; void __fastcall__ mouse_box (int minx, int miny, int maxx, int maxy);
;
-_mouse_box:
+.proc _mouse_box
+
ldy #0 ; Stack offset
add YCorr ; Adjust the Y value
jmp addysp1 ; Drop params, return
+.endproc
+
; --------------------------------------------------------------------------
;
; void __fastcall__ mouse_pos (struct mouse_pos* pos);
; /* Return the current mouse position */
;
-_mouse_pos:
+.proc _mouse_pos
+
sta ptr1
stx ptr1+1 ; Remember the argument pointer
rts ; Done
+.endproc
+
; --------------------------------------------------------------------------
;
; void __fastcall__ mouse_info (struct mouse_info* info);
; /* Return the state of the mouse buttons and the position of the mouse */
;
-_mouse_info:
+.proc _mouse_info
; We're cheating here to keep the code smaller: The first fields of the
; mouse_info struct are identical to the mouse_pos struct, so we will just
rts
+.endproc
+
; --------------------------------------------------------------------------
;
; void __fastcall__ mouse_move (int x, int y);
;
-_mouse_move:
+.proc _mouse_move
+
add YCorr ; Add Y coordinate correction
bcc @L1
inx
rts
+.endproc
+
; --------------------------------------------------------------------------
;
; unsigned char mouse_buttons (void);
;
-_mouse_buttons:
+.proc _mouse_buttons
+
lda #$00 ; Use port #0
jmp _readjoy ; Same as joystick
+.endproc
+
; --------------------------------------------------------------------------
;
; Mouse interrupt handler
;
+IRQDone:rts
+
MouseIRQ:
- cld
- lda SID_ADConv1 ; Get mouse X movement
+
+ lda Initialized ; Mouse initialized?
+ beq IRQDone ; Jump if no
+ lda SID_ADConv1 ; Get mouse X movement
ldy OldPotX
jsr MoveCheck ; Calculate movement vector
sty OldPotX
@L4: sty YPos
stx YPos+1
-; Move the mouse sprite if it is enabled
+; Move the mouse sprite to the current mouse position. Must be called
+; with interrupts off. MoveSprite1 is an entry without checking.
+
+MoveSprite:
+
+ lda Invisible ; Mouse visible?
+ bne Done ; Jump if no
+
+; Set the high X bit
+
+MoveSprite1:
+ lda VIC_SPR_HI_X ; Get high X bits of all sprites
+ and #$FE ; Clear bit for sprite #0
+ ldy XPos+1 ; Test Y position
+ beq @L5
+ ora #$01 ; Set high X bit
+@L5: sta VIC_SPR_HI_X ; Set hi X sprite values
+
+; Set the low X byte
- jsr MoveSprite ; Move the sprite
+ lda XPos
+ sta VIC_SPR0_X ; Set low byte
-; Jump to the next IRQ handler
+; Set the Y position
- jmp (OldIRQ)
+ ldy YPos+1 ; Negative or too large?
+ bne Done ; Jump if yes
+ lda YPos
+ sta VIC_SPR0_Y ; Set Y position
+; Done
+
+Done: rts
; --------------------------------------------------------------------------
;
; x/a = delta value for position
;
-MoveCheck:
+.proc MoveCheck
+
sty OldValue
sta NewValue
ldx #$00
@L2: txa ; A = $00
rts
-; --------------------------------------------------------------------------
-;
-; Move the mouse sprite to the current mouse position. Must be called
-; with interrupts off. MoveSprite1 is an entry without checking.
-;
-
-MoveSprite:
-
- lda Invisible ; Mouse visible?
- bne MoveSpriteDone ; Jump if no
-
-; Set the high X bit
-
-MoveSprite1:
- lda VIC_SPR_HI_X ; Get high X bits of all sprites
- and #$FE ; Clear bit for sprite #0
- ldy XPos+1 ; Test Y position
- beq @L1
- ora #$01 ; Set high X bit
-@L1: sta VIC_SPR_HI_X ; Set hi X sprite values
-
-; Set the low X byte
-
- lda XPos
- sta VIC_SPR0_X ; Set low byte
-
-; Set the Y position
-
- ldy YPos+1 ; Negative or too large?
- bne MoveSpriteDone ; Jump if yes
- lda YPos
- sta VIC_SPR0_Y ; Set Y position
-
-; Done
-
-MoveSpriteDone:
- rts
+.endproc
; --------------------------------------------------------------------------
; Data
.bss
-OldIRQ: .res 2 ; Old IRQ vector
+Initialized: .res 1 ; True if mouse initialized
+OldInitStatus: .res 1 ; Old IRQ flag value
OldValue: .res 1 ; Temp for MoveCheck routine
NewValue: .res 1 ; Temp for MoveCheck routine
YCorr: .res 1 ; Correction for Y coordinate
projects / cc65 / blobdiff