;
-; Default mouse callbacks for the Apple II
+; Default mouse callbacks for the Apple II
;
; Oliver Schmidt, 22.09.2005
;
-; All functions in this module should be interrupt safe, because they may
+; All functions in this module should be interrupt safe, because they may
; be called from an interrupt handler
;
- .ifdef __APPLE2ENH__
- .constructor initmcb
- .endif
- .export _mouse_def_callbacks
-
- .include "apple2.inc"
+ .export _mouse_def_callbacks
+
+ .include "apple2.inc"
; ------------------------------------------------------------------------
- .bss
-
-backup: .res 1
+ .bss
+
+backup: .res 1
+visible:.res 1
; ------------------------------------------------------------------------
- .rodata
+ .rodata
- ; Callback structure
+ ; Callback structure
_mouse_def_callbacks:
- .addr hide
- .addr show
- .addr movex
- .addr movey
+ .addr hide
+ .addr show
+ .addr prep
+ .addr draw
+ .addr movex
+ .addr movey
; ------------------------------------------------------------------------
- .segment "INIT"
+ .data
- .ifdef __APPLE2ENH__
-initmcb:
- lda ALTCHARSET ; Alternate charset switched in?
- bpl :+ ; No, normal charset
- lda #'B' ; MouseText character
- sta cmpcur+1
- sta getcur+1
-: rts
- .endif
-
-; ------------------------------------------------------------------------
-
- .data
+ .ifdef __APPLE2ENH__
+cursor = $42 ; Pointer MouseText character
+ .else
+cursor = '+' | $40 ; Flashing crosshair
+ .endif
getcursor:
.ifdef __APPLE2ENH__
bit RD80VID ; In 80 column mode?
- bpl column ; No, skip bank switching
-switch: bit LOWSCR ; Patched at runtime
+ bpl column ; No, skip bank switching
+switch: bit LOWSCR ; Patched at runtime
.endif
-column: ldx #$00 ; Patched at runtime
-getscr: lda $0400,x ; Patched at runtime
-cmpcur: cmp #'+' | $40 ; Possibly patched by initialization
- rts
+column: ldx #$00 ; Patched at runtime
+getscr: lda $0400,x ; Patched at runtime
+ cmp #cursor
+ rts
setcursor:
-getcur: lda #'+' | $40 ; Possibly patched by initialization
-setscr: sta $0400,x ; Patched at runtime
- .ifdef __APPLE2ENH__
- bit LOWSCR ; Doesn't hurt in 40 column mode
+ lda #cursor
+setscr: sta $0400,x ; Patched at runtime
+ .ifdef __APPLE2ENH__
+ bit LOWSCR ; Doesn't hurt in 40 column mode
.endif
- rts
+ rts
; ------------------------------------------------------------------------
- .code
+ .code
done:
- .ifdef __APPLE2ENH__
- bit LOWSCR ; Doesn't hurt in 40 column mode
+ .ifdef __APPLE2ENH__
+ bit LOWSCR ; Doesn't hurt in 40 column mode
.endif
- rts
+return: rts
; Hide the mouse cursor.
hide:
- jsr getcursor ; Cursor visible at current position?
- bne done ; No, we're done
- lda backup ; Get character at cursor position
- jmp setscr ; Draw character
+ dec visible
+ ; Fall through
+
+; Prepare to move the mouse cursor.
+prep:
+ jsr getcursor ; Cursor visible at current position?
+ bne done ; No, we're done
+ lda backup ; Get character at cursor position
+ jmp setscr ; Draw character
; Show the mouse cursor.
show:
- jsr getcursor ; Cursor visible at current position?
- beq done ; Yes, we're done
- sta backup ; Save character at cursor position
- jmp setcursor ; Draw cursor
+ inc visible
+ ; Fall through
+
+; Draw the mouse cursor.
+draw:
+ lda visible
+ beq return
+ jsr getcursor ; Cursor visible at current position?
+ beq done ; Yes, we're done
+ sta backup ; Save character at cursor position
+ jmp setcursor ; Draw cursor
; Move the mouse cursor x position to the value in A/X.
movex:
- dex ; Is position [256..279]?
- bmi :+ ; No, start with column 0
- clc
- adc #$0100 .MOD 7 ; Bias position
- ldx #$0100 / 7 - 1 ; Bias column
-: sec
-: sbc #7 ; 280 positions / 40 columns
- inx
- bcs :-
- stx column+1
+ dex ; Is position [256..279]?
+ bmi :+ ; No, start with column 0
+ clc
+ adc #$0100 .MOD 7 ; Bias position
+ ldx #$0100 / 7 - 1 ; Bias column
+: sec
+: sbc #7 ; 280 positions / 40 columns
+ inx
+ bcs :-
+ stx column+1
.ifdef __APPLE2ENH__
- adc #7 / 2 ; Left or right half of 40-col column?
- ldx #<LOWSCR ; Columns 1,3,5..79
- bcs :+
- .assert LOWSCR + 1 = HISCR, error
- inx ; Columns 0,2,4..78
-: stx switch+1
+ adc #7 / 2 ; Left or right half of 40-col column?
+ ldx #<LOWSCR ; Columns 1,3,5..79
+ bcs :+
+ .assert LOWSCR + 1 = HISCR, error
+ inx ; Columns 0,2,4..78
+: stx switch+1
.endif
- rts
+ rts
; Move the mouse cursor y position to the value in A/X.
movey:
- tax ; ABCDExxx
- lsr ; 0ABCDExx
- lsr ; 00ABCDEx
- lsr ; 000ABCDE
- sta getscr+1
- lsr ; 0000ABCD
- and #%00000011 ; 000000CD
- ora #>$0400 ; 000001CD
- sta getscr+2
- sta setscr+2
- txa ; ABCDExxx
- ror ; EABCDExx
- and #%11100000 ; EAB00000
- ora getscr+1 ; EABABCDE
- and #%11111000 ; EABAB000
- sta getscr+1
- sta setscr+1
- rts
+ tax ; ABCDExxx
+ lsr ; 0ABCDExx
+ lsr ; 00ABCDEx
+ lsr ; 000ABCDE
+ sta getscr+1
+ lsr ; 0000ABCD
+ and #%00000011 ; 000000CD
+ ora #>$0400 ; 000001CD
+ sta getscr+2
+ sta setscr+2
+ txa ; ABCDExxx
+ ror ; EABCDExx
+ and #%11100000 ; EAB00000
+ ora getscr+1 ; EABABCDE
+ and #%11111000 ; EABAB000
+ sta getscr+1
+ sta setscr+1
+ rts
projects / cc65 / blobdiff