Sweden-Number/graphics/vga.c

193 lines
5.3 KiB
C

/*
* VGA hardware emulation
*
* Copyright 1998 Ove Kåven (with some help from Marcus Meissner)
*
*/
#include <string.h>
#include "windows.h"
#include "winbase.h"
#include "miscemu.h"
#include "vga.h"
#include "ddraw.h"
#include "debug.h"
static IDirectDraw *lpddraw = NULL;
static IDirectDrawSurface *lpddsurf;
static IDirectDrawPalette *lpddpal;
static DDSURFACEDESC sdesc;
static WORD poll_timer;
static CRITICAL_SECTION vga_crit;
static int vga_polling,vga_refresh;
int VGA_SetMode(unsigned Xres,unsigned Yres,unsigned Depth)
{
if (lpddraw) VGA_Exit();
if (!lpddraw) {
DirectDrawCreate(NULL,&lpddraw,NULL);
if (!lpddraw) {
ERR(ddraw,"DirectDraw is not available\n");
return 1;
}
if (lpddraw->lpvtbl->fnSetDisplayMode(lpddraw,Xres,Yres,Depth)) {
ERR(ddraw,"DirectDraw does not support requested display mode\n");
lpddraw->lpvtbl->fnRelease(lpddraw);
lpddraw=NULL;
return 1;
}
lpddraw->lpvtbl->fnCreatePalette(lpddraw,0,NULL,&lpddpal,NULL);
memset(&sdesc,0,sizeof(sdesc));
sdesc.dwSize=sizeof(sdesc);
sdesc.dwFlags = DDSD_CAPS;
sdesc.ddsCaps.dwCaps = DDSCAPS_PRIMARYSURFACE;
if (lpddraw->lpvtbl->fnCreateSurface(lpddraw,&sdesc,&lpddsurf,NULL)||(!lpddsurf)) {
ERR(ddraw,"DirectDraw surface is not available\n");
lpddraw->lpvtbl->fnRelease(lpddraw);
lpddraw=NULL;
return 1;
}
vga_refresh=0;
InitializeCriticalSection(&vga_crit);
MakeCriticalSectionGlobal(&vga_crit);
/* poll every 20ms (50fps should provide adequate responsiveness) */
poll_timer = CreateSystemTimer( 20, VGA_Poll );
}
return 0;
}
int VGA_GetMode(unsigned*Height,unsigned*Width,unsigned*Depth)
{
if (!lpddraw) return 1;
if (!lpddsurf) return 1;
if (Height) *Height=sdesc.dwHeight;
if (Width) *Width=sdesc.dwWidth;
if (Depth) *Depth=sdesc.ddpfPixelFormat.x.dwRGBBitCount;
return 0;
}
void VGA_Exit(void)
{
if (lpddraw) {
SYSTEM_KillSystemTimer(poll_timer);
DeleteCriticalSection(&vga_crit);
lpddsurf->lpvtbl->fnRelease(lpddsurf);
lpddsurf=NULL;
lpddraw->lpvtbl->fnRelease(lpddraw);
lpddraw=NULL;
}
}
void VGA_SetPalette(PALETTEENTRY*pal,int start,int len)
{
if (!lpddraw) return;
lpddpal->lpvtbl->fnSetEntries(lpddpal,0,start,len,pal);
lpddsurf->lpvtbl->fnSetPalette(lpddsurf,lpddpal);
}
void VGA_SetQuadPalette(RGBQUAD*color,int start,int len)
{
PALETTEENTRY pal[256];
int c;
if (!lpddraw) return;
for (c=0; c<len; c++) {
pal[c].peRed =color[c].rgbRed;
pal[c].peGreen=color[c].rgbGreen;
pal[c].peBlue =color[c].rgbBlue;
pal[c].peFlags=0;
}
lpddpal->lpvtbl->fnSetEntries(lpddpal,0,start,len,pal);
lpddsurf->lpvtbl->fnSetPalette(lpddsurf,lpddpal);
}
LPSTR VGA_Lock(unsigned*Pitch,unsigned*Height,unsigned*Width,unsigned*Depth)
{
if (!lpddraw) return NULL;
if (!lpddsurf) return NULL;
if (lpddsurf->lpvtbl->fnLock(lpddsurf,NULL,&sdesc,0,0)) {
ERR(ddraw,"could not lock surface!\n");
return NULL;
}
if (Pitch) *Pitch=sdesc.lPitch;
if (Height) *Height=sdesc.dwHeight;
if (Width) *Width=sdesc.dwWidth;
if (Depth) *Depth=sdesc.ddpfPixelFormat.x.dwRGBBitCount;
return sdesc.y.lpSurface;
}
void VGA_Unlock(void)
{
lpddsurf->lpvtbl->fnUnlock(lpddsurf,sdesc.y.lpSurface);
}
/* We are called from SIGALRM, aren't we? We should _NOT_ do synchronization
* stuff!
*/
void VGA_Poll( WORD timer )
{
char *dat;
unsigned Pitch,Height,Width;
char *surf;
int Y;
/* int X; */
EnterCriticalSection(&vga_crit);
if (!vga_polling) {
vga_polling++;
LeaveCriticalSection(&vga_crit);
/* FIXME: optimize by doing this only if the data has actually changed
* (in a way similar to DIBSection, perhaps) */
surf = VGA_Lock(&Pitch,&Height,&Width,NULL);
if (!surf) return;
dat = DOSMEM_MapDosToLinear(0xa0000);
/* copy from virtual VGA frame buffer to DirectDraw surface */
for (Y=0; Y<Height; Y++,surf+=Pitch,dat+=Width) {
memcpy(surf,dat,Width);
/*for (X=0; X<Width; X++) if (dat[X]) TRACE(ddraw,"data(%d) at (%d,%d)\n",dat[X],X,Y);*/
}
VGA_Unlock();
vga_refresh=1;
EnterCriticalSection(&vga_crit);
vga_polling--;
}
LeaveCriticalSection(&vga_crit);
}
static BYTE palreg,palcnt;
static PALETTEENTRY paldat;
void VGA_ioport_out( WORD port, BYTE val )
{
switch (port) {
case 0x3c8:
palreg=val; palcnt=0; break;
case 0x3c9:
((BYTE*)&paldat)[palcnt++]=val << 2;
if (palcnt==3) {
VGA_SetPalette(&paldat,palreg,1);
palreg++;
}
break;
}
}
BYTE VGA_ioport_in( WORD port )
{
BYTE ret;
switch (port) {
case 0x3da:
/* since we don't (yet?) serve DOS VM requests while VGA_Poll is running,
we need to fake the occurrence of the vertical refresh */
if (lpddraw) {
ret=vga_refresh?0x00:0x08;
vga_refresh=0;
} else ret=0x08;
break;
default:
ret=0xff;
}
return ret;
}