graphics/vga.c

   1 /*
   2  * VGA hardware emulation
   3  *
   4  * Copyright 1998 Ove Kåven (with some help from Marcus Meissner)
   5  *
   6  */
   7
   8 #include <string.h>
   9 #include "windows.h"
  10 #include "winbase.h"
  11 #include "miscemu.h"
  12 #include "vga.h"
  13 #include "compobj.h"
  14 #include "interfaces.h"
  15 #include "ddraw.h"
  16 #include "debug.h"
  17
  18 static IDirectDraw *lpddraw = NULL;
  19 static IDirectDrawSurface *lpddsurf;
  20 static IDirectDrawPalette *lpddpal;
  21 static DDSURFACEDESC sdesc;
  22 static WORD poll_timer;
  23 static CRITICAL_SECTION vga_crit;
  24 static int vga_polling,vga_refresh;
  25
  26 int VGA_SetMode(unsigned Xres,unsigned Yres,unsigned Depth)
  27 {
  28     if (lpddraw) VGA_Exit();
  29     if (!lpddraw) {
  30         DirectDrawCreate(NULL,&lpddraw,NULL);
  31         if (!lpddraw) {
  32             ERR(ddraw,"DirectDraw is not available\n");
  33             return 1;
  34         }
  35         if (lpddraw->lpvtbl->fnSetDisplayMode(lpddraw,Xres,Yres,Depth)) {
  36             ERR(ddraw,"DirectDraw does not support requested display mode\n");
  37             lpddraw->lpvtbl->fnRelease(lpddraw);
  38             lpddraw=NULL;
  39             return 1;
  40         }
  41         lpddraw->lpvtbl->fnCreatePalette(lpddraw,0,NULL,&lpddpal,NULL);
  42         memset(&sdesc,0,sizeof(sdesc));
  43         sdesc.dwSize=sizeof(sdesc);
  44         if (lpddraw->lpvtbl->fnCreateSurface(lpddraw,&sdesc,&lpddsurf,NULL)||(!lpddsurf)) {
  45             ERR(ddraw,"DirectDraw surface is not available\n");
  46             lpddraw->lpvtbl->fnRelease(lpddraw);
  47             lpddraw=NULL;
  48             return 1;
  49         }
  50         vga_refresh=0;
  51         InitializeCriticalSection(&vga_crit);
  52         /* poll every 20ms (50fps should provide adequate responsiveness) */
  53         poll_timer = CreateSystemTimer( 20, (FARPROC16)VGA_Poll );
  54     }
  55     return 0;
  56 }
  57
  58 int VGA_GetMode(unsigned*Height,unsigned*Width,unsigned*Depth)
  59 {
  60     if (!lpddraw) return 1;
  61     if (!lpddsurf) return 1;
  62     if (Height) *Height=sdesc.dwHeight;
  63     if (Width) *Width=sdesc.dwWidth;
  64     if (Depth) *Depth=sdesc.ddpfPixelFormat.x.dwRGBBitCount;
  65     return 0;
  66 }
  67
  68 void VGA_Exit(void)
  69 {
  70     if (lpddraw) {
  71         SYSTEM_KillSystemTimer(poll_timer);
  72         DeleteCriticalSection(&vga_crit);
  73         lpddsurf->lpvtbl->fnRelease(lpddsurf);
  74         lpddsurf=NULL;
  75         lpddraw->lpvtbl->fnRelease(lpddraw);
  76         lpddraw=NULL;
  77     }
  78 }
  79
  80 void VGA_SetPalette(PALETTEENTRY*pal,int start,int len)
  81 {
  82     if (!lpddraw) return;
  83     lpddpal->lpvtbl->fnSetEntries(lpddpal,0,start,len,pal);
  84     lpddsurf->lpvtbl->fnSetPalette(lpddsurf,lpddpal);
  85 }
  86
  87 void VGA_SetQuadPalette(RGBQUAD*color,int start,int len)
  88 {
  89     PALETTEENTRY pal[256];
  90     int c;
  91
  92     if (!lpddraw) return;
  93     for (c=0; c<len; c++) {
  94         pal[c].peRed  =color[c].rgbRed;
  95         pal[c].peGreen=color[c].rgbGreen;
  96         pal[c].peBlue =color[c].rgbBlue;
  97         pal[c].peFlags=0;
  98     }
  99     lpddpal->lpvtbl->fnSetEntries(lpddpal,0,start,len,pal);
 100     lpddsurf->lpvtbl->fnSetPalette(lpddsurf,lpddpal);
 101 }
 102
 103 LPSTR VGA_Lock(unsigned*Pitch,unsigned*Height,unsigned*Width,unsigned*Depth)
 104 {
 105     if (!lpddraw) return NULL;
 106     if (!lpddsurf) return NULL;
 107     if (lpddsurf->lpvtbl->fnLock(lpddsurf,NULL,&sdesc,0,0)) {
 108         ERR(ddraw,"could not lock surface!\n");
 109         return NULL;
 110     }
 111     if (Pitch) *Pitch=sdesc.lPitch;
 112     if (Height) *Height=sdesc.dwHeight;
 113     if (Width) *Width=sdesc.dwWidth;
 114     if (Depth) *Depth=sdesc.ddpfPixelFormat.x.dwRGBBitCount;
 115     return sdesc.y.lpSurface;
 116 }
 117
 118 void VGA_Unlock(void)
 119 {
 120     lpddsurf->lpvtbl->fnUnlock(lpddsurf,sdesc.y.lpSurface);
 121 }
 122
 123 void VGA_Poll(void)
 124 {
 125     char *dat;
 126     unsigned Pitch,Height,Width;
 127     char *surf;
 128     int Y,X;
 129
 130     EnterCriticalSection(&vga_crit);
 131     if (!vga_polling) {
 132         vga_polling++;
 133         LeaveCriticalSection(&vga_crit);
 134         /* FIXME: optimize by doing this only if the data has actually changed
 135          *        (in a way similar to DIBSection, perhaps) */
 136         surf = VGA_Lock(&Pitch,&Height,&Width,NULL);
 137         if (!surf) return;
 138         dat = DOSMEM_MapDosToLinear(0xa0000);
 139         /* copy from virtual VGA frame buffer to DirectDraw surface */
 140         for (Y=0; Y<Height; Y++,surf+=Pitch,dat+=Width) {
 141             memcpy(surf,dat,Width);
 142             for (X=0; X<Width; X++) if (dat[X]) TRACE(ddraw,"data(%d) at (%d,%d)\n",dat[X],X,Y);
 143         }
 144         VGA_Unlock();
 145         vga_refresh=1;
 146         EnterCriticalSection(&vga_crit);
 147         vga_polling--;
 148     }
 149     LeaveCriticalSection(&vga_crit);
 150 }
 151
 152 static BYTE palreg,palcnt;
 153 static PALETTEENTRY paldat;
 154
 155 void VGA_ioport_out( WORD port, BYTE val )
 156 {
 157     switch (port) {
 158         case 0x3c8:
 159             palreg=val; palcnt=0; break;
 160         case 0x3c9:
 161             ((BYTE*)&paldat)[palcnt++]=val << 2;
 162             if (palcnt==3) {
 163                 VGA_SetPalette(&paldat,palreg,1);
 164                 palreg++;
 165             }
 166             break;
 167     }
 168 }
 169
 170 BYTE VGA_ioport_in( WORD port )
 171 {
 172     BYTE ret;
 173
 174     switch (port) {
 175         case 0x3da:
 176             /* since we don't (yet?) serve DOS VM requests while VGA_Poll is running,
 177                we need to fake the occurrence of the vertical refresh */
 178             if (lpddraw) {
 179                 ret=vga_refresh?0x00:0x08;
 180                 vga_refresh=0;
 181             } else ret=0x08;
 182             break;
 183         default:
 184             ret=0xff;
 185     }
 186     return ret;
 187 }