2 * VGA hardware emulation
4 * Copyright 1998 Ove Kåven (with some help from Marcus Meissner)
16 static IDirectDraw
*lpddraw
= NULL
;
17 static IDirectDrawSurface
*lpddsurf
;
18 static IDirectDrawPalette
*lpddpal
;
19 static DDSURFACEDESC sdesc
;
20 static WORD poll_timer
;
21 static CRITICAL_SECTION vga_crit
;
22 static int vga_polling
,vga_refresh
;
24 int VGA_SetMode(unsigned Xres
,unsigned Yres
,unsigned Depth
)
26 if (lpddraw
) VGA_Exit();
28 DirectDrawCreate(NULL
,&lpddraw
,NULL
);
30 ERR(ddraw
,"DirectDraw is not available\n");
33 if (lpddraw
->lpvtbl
->fnSetDisplayMode(lpddraw
,Xres
,Yres
,Depth
)) {
34 ERR(ddraw
,"DirectDraw does not support requested display mode\n");
35 lpddraw
->lpvtbl
->fnRelease(lpddraw
);
39 lpddraw
->lpvtbl
->fnCreatePalette(lpddraw
,DDPCAPS_8BIT
,NULL
,&lpddpal
,NULL
);
40 memset(&sdesc
,0,sizeof(sdesc
));
41 sdesc
.dwSize
=sizeof(sdesc
);
42 sdesc
.dwFlags
= DDSD_CAPS
;
43 sdesc
.ddsCaps
.dwCaps
= DDSCAPS_PRIMARYSURFACE
;
44 if (lpddraw
->lpvtbl
->fnCreateSurface(lpddraw
,&sdesc
,&lpddsurf
,NULL
)||(!lpddsurf
)) {
45 ERR(ddraw
,"DirectDraw surface is not available\n");
46 lpddraw
->lpvtbl
->fnRelease(lpddraw
);
51 InitializeCriticalSection(&vga_crit
);
52 MakeCriticalSectionGlobal(&vga_crit
);
53 /* poll every 20ms (50fps should provide adequate responsiveness) */
54 poll_timer
= CreateSystemTimer( 20, VGA_Poll
);
59 int VGA_GetMode(unsigned*Height
,unsigned*Width
,unsigned*Depth
)
61 if (!lpddraw
) return 1;
62 if (!lpddsurf
) return 1;
63 if (Height
) *Height
=sdesc
.dwHeight
;
64 if (Width
) *Width
=sdesc
.dwWidth
;
65 if (Depth
) *Depth
=sdesc
.ddpfPixelFormat
.x
.dwRGBBitCount
;
72 SYSTEM_KillSystemTimer(poll_timer
);
73 DeleteCriticalSection(&vga_crit
);
74 lpddsurf
->lpvtbl
->fnRelease(lpddsurf
);
76 lpddraw
->lpvtbl
->fnRelease(lpddraw
);
81 void VGA_SetPalette(PALETTEENTRY
*pal
,int start
,int len
)
84 lpddpal
->lpvtbl
->fnSetEntries(lpddpal
,0,start
,len
,pal
);
85 lpddsurf
->lpvtbl
->fnSetPalette(lpddsurf
,lpddpal
);
88 void VGA_SetQuadPalette(RGBQUAD
*color
,int start
,int len
)
90 PALETTEENTRY pal
[256];
94 for (c
=0; c
<len
; c
++) {
95 pal
[c
].peRed
=color
[c
].rgbRed
;
96 pal
[c
].peGreen
=color
[c
].rgbGreen
;
97 pal
[c
].peBlue
=color
[c
].rgbBlue
;
100 lpddpal
->lpvtbl
->fnSetEntries(lpddpal
,0,start
,len
,pal
);
101 lpddsurf
->lpvtbl
->fnSetPalette(lpddsurf
,lpddpal
);
104 LPSTR
VGA_Lock(unsigned*Pitch
,unsigned*Height
,unsigned*Width
,unsigned*Depth
)
106 if (!lpddraw
) return NULL
;
107 if (!lpddsurf
) return NULL
;
108 if (lpddsurf
->lpvtbl
->fnLock(lpddsurf
,NULL
,&sdesc
,0,0)) {
109 ERR(ddraw
,"could not lock surface!\n");
112 if (Pitch
) *Pitch
=sdesc
.lPitch
;
113 if (Height
) *Height
=sdesc
.dwHeight
;
114 if (Width
) *Width
=sdesc
.dwWidth
;
115 if (Depth
) *Depth
=sdesc
.ddpfPixelFormat
.x
.dwRGBBitCount
;
116 return sdesc
.y
.lpSurface
;
119 void VGA_Unlock(void)
121 lpddsurf
->lpvtbl
->fnUnlock(lpddsurf
,sdesc
.y
.lpSurface
);
124 /* We are called from SIGALRM, aren't we? We should _NOT_ do synchronization
127 void VGA_Poll( WORD timer
)
130 unsigned Pitch
,Height
,Width
;
135 EnterCriticalSection(&vga_crit
);
138 LeaveCriticalSection(&vga_crit
);
139 /* FIXME: optimize by doing this only if the data has actually changed
140 * (in a way similar to DIBSection, perhaps) */
141 surf
= VGA_Lock(&Pitch
,&Height
,&Width
,NULL
);
143 dat
= DOSMEM_MapDosToLinear(0xa0000);
144 /* copy from virtual VGA frame buffer to DirectDraw surface */
145 for (Y
=0; Y
<Height
; Y
++,surf
+=Pitch
,dat
+=Width
) {
146 memcpy(surf
,dat
,Width
);
147 /*for (X=0; X<Width; X++) if (dat[X]) TRACE(ddraw,"data(%d) at (%d,%d)\n",dat[X],X,Y);*/
151 EnterCriticalSection(&vga_crit
);
154 LeaveCriticalSection(&vga_crit
);
157 static BYTE palreg
,palcnt
;
158 static PALETTEENTRY paldat
;
160 void VGA_ioport_out( WORD port
, BYTE val
)
164 palreg
=val
; palcnt
=0; break;
166 ((BYTE
*)&paldat
)[palcnt
++]=val
<< 2;
168 VGA_SetPalette(&paldat
,palreg
,1);
175 BYTE
VGA_ioport_in( WORD port
)
181 /* since we don't (yet?) serve DOS VM requests while VGA_Poll is running,
182 we need to fake the occurrence of the vertical refresh */
184 ret
=vga_refresh
?0x00:0x08;