xmouse.asm

视频游戏开发源码

;-----------------------------------------------------------------------
; MODULE XMOUSE
;
; Mouse functions functions for all MODE X 256 Color resolutions
;
; Compile with Tasm.
; C callable.
;
; ****** XLIB - Mode X graphics library                ****************
; ******                                               ****************
; ****** Written By Themie Gouthas                     ****************
;
; This module is based on Shane Hyde's module of the same name,
; posted to Rec.Games.Programmer, October 92.
;
;
; [e-mail]
; [e-mail]
;
; mouse cursor shape by Tiaan A Geldenhuys
;
;-----------------------------------------------------------------------

COMMENT  $


This is a module implementing very basic mouse functions.

It does not support the full functionality of:

  SPLIT SCREENS
  SCROLLED WINDOWS
  VIRTUAL WINDOWS

	      --------------------------------------

	      MS Mouse Driver Functions

	      Mouse Initialization                 0
	      Show Cursor                          1
	      Hide Cursor                          2
	      Get Mouse Position & Button Status   3
	      Set Mouse Cursor Position            4
	      Get Button Press Information         5
	      Get Button Release Information       6
	      Set Min/Max Horizontal Position      7
	      Set Min/Max Vertical Position        8
	      Define Graphics Cursor Block         9
	      Define Text Cursor                  10
	      Read Mouse Motion Counters          11
	      Define Event Handler                12
	      Light Pen Emulation Mode ON         13
	      Light Pen Emulation Mode OFF        14
	      Set Mouse Mickey/Pixel Ratio        15
	      Conditional Hide Cursor             16
	      Set Double-Speed Threshold          19
	      --------------------------------------
$

include xlib.inc
include xdetect.inc

.data

global   _MouseInstalled    :word
global   _MouseHidden       :word
global   _MouseButtonStatus :word
global   _MouseX            :word
global   _MouseY            :word
global   _MouseFrozen       :byte
global   _MouseColor        :byte

global   _x_define_mouse_cursor :proc
global   _x_show_mouse          :proc
global   _x_hide_mouse          :proc
global   _x_mouse_remove        :proc
global   _x_position_mouse      :proc
global   _x_put_cursor          :proc
global   _x_update_mouse        :proc
global   _x_mouse_init          :proc
global   _x_mouse_window        :proc


ALIGN 2



      InitMouseDef db 00000001b  ; Default mouse mask, note the reverse order
		db 00000011b
		db 00000111b
		db 00001111b
		db 00011111b
		db 00111111b
		db 01111111b
		db 11111111b
		db 00011111b
		db 00011011b
		db 00110001b
		db 00110000b
		db 01100000b
		db 01100000b



COMMENT $

   Old mouse definition

   InitMouseDef db 00000001b  ; Default mouse mask, note the reverse order
		db 00000011b
		db 00000111b
		db 00001111b
		db 00011111b
		db 00111111b
		db 01111111b
		db 11111111b
		db 00011100b
		db 00111100b
		db 01111100b
		db 00000000b
		db 00000000b
		db 00000000b

$

    MouseMask          db 168 dup(?)
    OldHandlerSeg      dw  ?
    OldHandlerOffs     dw  ?
    OldHandlerMask     dw  ?
    OldX               dw  ?
    OldY               dw  ?
    OldScrnOffs        dw  ?

    BGSaveOffs         dw  0

   _MouseInstalled     dw 0     ; Flag indicating whether mouse is installed
   _MouseHidden        dw 0     ; Flag indicating whether mouse is hidden
   _MouseButtonStatus  dw 0     ; Holds current button press information
   _MouseX             dw 0     ; Coords of cursor hot spot
   _MouseY             dw 0
   _MouseFrozen        db 0     ; Mouse motion enable/disable control
   _MouseColor         db 0     ; Mouse cursor colour

   inhandler           db 0
.code

;----------------------------------------------------------------------
; Local function that updates the cursor position
;
; Destroys SI,DI,AX,BX
;
;----------------------------------------------------------------------
proc update_cursor near
   WaitVsyncStart

   mov di,[OldScrnOffs]             ; Delete cursor (restore old background)
   mov ax,[OldY]
   mov bx,[OldX]

   call restorebg

   mov si,[_VisiblePageOffs]        ; Save cursor background
   mov ax,[_MouseY]
   mov bx,[_MouseX]
   mov [OldScrnOffs],si
   mov [OldY],ax
   mov [OldX],bx
   call getbg

   push [_VisiblePageOffs]          ; Draw the cursor
   mov  ax,[_ScrnPhysicalHeight]
   push ax
   mov  ax,0
   push ax
   push [OldY]
   push [OldX]
   call _x_put_cursor
   add  sp,10
   ret
update_cursor endp


;----------------------------------------------------------------------
; x_mouse_init - Initialise Mode X mouse handler
;
; C Prototype
;
;  int x_mouse_init()
;
; This is the first function you must call before using any of the mouse
; functions
;
; WARNING: This function uses and updates "NonVisual_Offset" to allocate
;          video ram for the saved mouse background.
;
; This mouse code uses the fastest possible techniques to save and restore
; mouse backgrounds and to draw the mouse cursor.
;
; LIMITATIONS: No clipping is supported horizontally for the mouse cursor
;              No validity checking is performed for NonVisual_Offs
;
;
; **WARNING** Hide or freeze mouse while drawing using any of the other
;             Modules. VGA register settings are not preserved which will
;             result in unpredictable drawing behavior.
;             If you know the drawing will occur away from the mouse cursor
;             set MouseFrozen to TRUE (1), do your drawing then set it to
;             FALSE (0). Alternatively call "x_hide_mouse", perform your
;             drawing and then call "x_show_mouse"
;
;
; Written by Themie Gouthas
;----------------------------------------------------------------------
_x_mouse_init proc
     push  bp
     mov   bp,sp

     cmp   [_MouseButtonCount],0  ; Dont initialize if mouse detection
     jne   @@DontInitialize       ; or initialization function previously
				  ;   called
     xor   ax,ax                  ; FUNC 0: Mouse Initialization
     int   33h                    ;
     or    ax,ax                  ; Is there a mouse installed ?
     jz    @@Done
     mov   [_MouseButtonCount],bx ; Set the button count

@@DontInitialize:

     mov   [_MouseInstalled],ax
     or    ax,ax                  ; Do we have an installed mouse driver ?
     jz    @@Done                 ; Nop!

     mov   ax,[_NonVisual_Offs];  ; Allocate VRAM for saved background
     mov   BGSaveOffs,ax

     add   ax,14*3
     mov   [_NonVisual_Offs],ax   ; Update NonVisualOffset

     mov   ax,02                  ; FUNC 2: Hide Cursor
     int   33h                    ;  (hide the mouse driver's default cursor)
     mov   _MouseInstalled,TRUE   ; Indicate user mouse driver present

     mov   ax,07h                 ; FUNC 7:Set min/max horizontal position
     mov   cx,0
     mov   dx,[_ScrnPhysicalPixelWidth]
     shl   dx,1                   ; Mult X by 2 as cursor steps by 2 pixels
     int   33h                    ; 0 < X < _ScrnPhysicalPixelWidth

     mov   ax,08h                 ; FUNC 8:Set min/max vertical position
     mov   cx,0
     mov   dx,_ScrnPhysicalHeight
     int   33h                    ; 0 < Y < _ScrnPhysicalHeight

     mov   ax,0fh                 ; FUNC 15: Mouse Hor/Vert resolution
     mov   cx,4                   ; Horiz speed  >> Value => << Speed
     mov   dx,8                   ; Vert Speed
     int   33h

     mov   ax,3                   ; FUNC 3: Get mouse pos & button status
     int   33h
     mov   [_MouseY],dx
     shr   cx,1
     mov   [_MouseX],cx

     mov   ax,12                  ; FUNC 12: Define Event Handler
     mov   bx,seg mouse_handler   ;  ES:DX -> Event handler
     mov   es,bx
     mov   dx,offset mouse_handler
     mov   cx,1fh                 ;  Set handler for all events
     int   33h



     mov   [_MouseHidden],TRUE    ; Mouse initially hidden

     push  ds                     ; Set the default cursor shape
     mov   ax,offset InitMouseDef
     push  ax
     call  _x_define_mouse_cursor
     add   sp,04h

     mov   ax,[_MouseInstalled]   ; Return MouseInstalled flag
@@Done:
     pop   bp
     ret
_x_mouse_init endp

;----------------------------------------------------------------------
; x_mouse_window - Define a mouse window
;
; C Prototype
;
;  void x_mouse_window(int x0, int y0, int x1, int y1);
;
;
; Written by Themie Gouthas
;----------------------------------------------------------------------
_x_mouse_window proc
ARG x0:word,y0:word,x1:word,y1:word
     push  bp
     mov   bp,sp

     mov   ax,7       ; FUNC 7: Set X range
     mov   cx,x0
     shl   cx,1
     mov   dx,x1
     shl   dx,1
     int   33h

     mov   ax,8       ; FUNC 8: Set Y range
     mov   cx,y0
     mov   dx,y1
     int   33h
     pop   bp
     ret
_x_mouse_window endp


;----------------------------------------------------------------------
; x_define_mouse_cursor - Define a mouse cursor from an input bitmask
;
; C Prototype
;
;  void x_define_mouse_cursor(char far *MouseDef, unsigned char MouseColor)
;
; WARNING: This function assumes MouseDef points to 14 bytes.
;
; Note: Bit order is in reverse. ie bit 7 represents pixel 0 ..
;       bit 0 represents pixel 7 in each "MouseDef" byte.
;
; Written by Themie Gouthas
;----------------------------------------------------------------------
_x_define_mouse_cursor proc
ARG MouseDef:dword,MouseColor:byte
     push  bp
     mov   bp,sp

     cmp  [_MouseInstalled],FALSE   ; Check whether we have installed
     je   @@Done                    ;  our mouse handler and leave if not

     mov  al,[MouseColor]           ; Set the mouse pointers color
     mov  [_MouseColor],al

     push  si
     push  di
     push  ds
     mov   ax,ds                ; ES:DI -> Stored plane mask for all
     mov   es,ax                ;   pixel alignments of mouse cursor
     mov   di,offset MouseMask
     lds   si,MouseDef
     xor   cl,cl                ; CL = current alignment (initially zero)
@@AlignmentLoop:
     push  si                   ; save MouseDef ptr for next alignment
     mov   dh,14                ; Init Row counter to Cursor Height
@@RowLoop:
     lodsb                      ; Load first cursor def byte each bit
				;  representing pixel in the row
     xor   ah,ah                ; AH is the shift overflow byte
     shl   ax,cl                ; Shift mask for current alignment

     mov   bl,al                ; store first three nibbles of ax into
     and   bl,0fh               ;  consecutive bytes in the destination
     mov   es:[di],bl           ;  buffer
     inc   di
     shr   al,4
     stosw

     dec   dh                   ; Next row for this alignment if there
     jnz   @@RowLoop            ;  are more to do

     pop   si                   ; point to the start of the cursor def.
     inc   cl                   ; Select next pixel alignment
     cmp   cl,4                 ; If there are more alignments to do
     jne   @@AlignmentLoop      ;   then jump

     pop   ds
     pop   di
     pop   si
@@Done:
     pop   bp
     ret
_x_define_mouse_cursor endp


;----------------------------------------------------------------------
; x_show_mouse - Shows a previously hidden mouse cursor
;
; C Prototype
;
;  void x_show_mouse()
;
; Written by Themie Gouthas
;----------------------------------------------------------------------
_x_show_mouse proc
     push  bp
     mov   bp,sp
     cmp   [_MouseInstalled],FALSE  ; Make sure our handler is installed
     je    @@Done
     cmp   [_MouseHidden],FALSE     ; If not hidden then exit
     je    @@Done
     push  si
     push  di


@@WaitEndOfHandler:               ; Make sure handler not currently active
     mov   cl,[inhandler]
     or    cl,cl
     jnz   @@WaitEndOfHandler


     mov   si,[_VisiblePageOffs]  ; Save mouse background and pos details
     mov   ax,[_MouseY]
     mov   bx,[_MouseX]
     mov   [OldScrnOffs],si
     mov   [OldY],ax
     mov   [OldX],bx
     call  getbg

     push [_VisiblePageOffs]      ; Draw cursor
     push [_ScrnLogicalHeight]
     xor  ax,ax
     push ax
     push [OldY]
     push [OldX]
     call _x_put_cursor
     add  sp,10

     mov   [_MouseHidden],FALSE   ; Indicate mouse cursor no longer hidden

     pop  di
     pop  si
@@Done:
     pop   bp
     ret
_x_show_mouse endp


;----------------------------------------------------------------------
; x_hide_mouse - Hides a previously visible mouse cursor
;
; C Prototype
;
;  void x_hide_mouse()