common.h

gameboy游戏模拟器,COMMON.H CONV.C DASM.C DEBUG.C FILE_ID.DIZ FMFREQS.C FMFREQS.H GB.C GB.H GBLIST.C HEL

/** VGB: portable GameBoy emulator ***************************/
/**                                                         **/
/**                        Common.h                         **/
/**                                                         **/
/** This file contains parts of the drivers which are       **/
/** common for both Unix/X and MSDOS.                       **/
/**                                                         **/
/** Copyright (C) Marat Fayzullin 1995,1996                 **/
/**               John Stiles     1996                      **/
/**               Marcel de Kogel 1996                      **/
/**     You are not allowed to distribute this software     **/
/**     commercially. Please, notify me, if you make any    **/   
/**     changes to this file.                               **/
/*************************************************************/

/** USE_XPAL *************************************************/
/** When defined, it makes Common.h drivers use XPal[] to   **/
/** obtain color numbers (when there is no 1:1              **/
/** correspondence, for example in X11).                    **/
/*************************************************************/
#define USE_XPAL

#ifdef USE_XPAL
#define XPAL(N) XPal[N]
#else
#define XPAL(N) N
#endif

/****************************************************************/
/*** Refresh a line.                                          ***/
/****************************************************************/
void RefreshLine(byte Y)
{
  /* Conversion matrix where result has bits */
  /* flipped over and inverted.              */
  static byte spriteconv[256] =
  {
    0xFF,0x7F,0xBF,0x3F,0xDF,0x5F,0x9F,0x1F,0xEF,0x6F,0xAF,0x2F,
    0xCF,0x4F,0x8F,0x0F,0xF7,0x77,0xB7,0x37,0xD7,0x57,0x97,0x17,
    0xE7,0x67,0xA7,0x27,0xC7,0x47,0x87,0x07,0xFB,0x7B,0xBB,0x3B,
    0xDB,0x5B,0x9B,0x1B,0xEB,0x6B,0xAB,0x2B,0xCB,0x4B,0x8B,0x0B,
    0xF3,0x73,0xB3,0x33,0xD3,0x53,0x93,0x13,0xE3,0x63,0xA3,0x23,
    0xC3,0x43,0x83,0x03,0xFD,0x7D,0xBD,0x3D,0xDD,0x5D,0x9D,0x1D,
    0xED,0x6D,0xAD,0x2D,0xCD,0x4D,0x8D,0x0D,0xF5,0x75,0xB5,0x35,
    0xD5,0x55,0x95,0x15,0xE5,0x65,0xA5,0x25,0xC5,0x45,0x85,0x05,
    0xF9,0x79,0xB9,0x39,0xD9,0x59,0x99,0x19,0xE9,0x69,0xA9,0x29,
    0xC9,0x49,0x89,0x09,0xF1,0x71,0xB1,0x31,0xD1,0x51,0x91,0x11,
    0xE1,0x61,0xA1,0x21,0xC1,0x41,0x81,0x01,0xFE,0x7E,0xBE,0x3E,
    0xDE,0x5E,0x9E,0x1E,0xEE,0x6E,0xAE,0x2E,0xCE,0x4E,0x8E,0x0E,
    0xF6,0x76,0xB6,0x36,0xD6,0x56,0x96,0x16,0xE6,0x66,0xA6,0x26,
    0xC6,0x46,0x86,0x06,0xFA,0x7A,0xBA,0x3A,0xDA,0x5A,0x9A,0x1A,
    0xEA,0x6A,0xAA,0x2A,0xCA,0x4A,0x8A,0x0A,0xF2,0x72,0xB2,0x32,
    0xD2,0x52,0x92,0x12,0xE2,0x62,0xA2,0x22,0xC2,0x42,0x82,0x02,
    0xFC,0x7C,0xBC,0x3C,0xDC,0x5C,0x9C,0x1C,0xEC,0x6C,0xAC,0x2C,
    0xCC,0x4C,0x8C,0x0C,0xF4,0x74,0xB4,0x34,0xD4,0x54,0x94,0x14,
    0xE4,0x64,0xA4,0x24,0xC4,0x44,0x84,0x04,0xF8,0x78,0xB8,0x38,
    0xD8,0x58,0x98,0x18,0xE8,0x68,0xA8,0x28,0xC8,0x48,0x88,0x08,
    0xF0,0x70,0xB0,0x30,0xD0,0x50,0x90,0x10,0xE0,0x60,0xA0,0x20,
    0xC0,0x40,0x80,0x00
  };
  byte *X;
  byte ZBuf[44];
  byte Offset,*P,*T,*R,*Z,Z0,D0,X1,X2;
  unsigned int D1;
  byte N,*S;
  unsigned K;
  int shift;

#ifdef USE_XPAL
#define PAL(N)  Pal[N]
#define WPAL(N) WPal[N]
  byte Pal[4],WPal[4];
  Pal[0]=XPal[BPal[0]];Pal[1]=XPal[BPal[1]];
  Pal[2]=XPal[BPal[2]];Pal[3]=XPal[BPal[3]];
  WPal[0]=(XPal+8)[BPal[0]];WPal[1]=(XPal+8)[BPal[1]];
  WPal[2]=(XPal+8)[BPal[2]];WPal[3]=(XPal+8)[BPal[3]];
#else
#define PAL(N)  BPal[N]
#define WPAL(N) BPal[N]+8
#endif

  X=R=XBuf+WIDTH*Y+(WIDTH-160)/2;
  Z=ZBuf;

  if((LCDCONT&0x81)!=0x81)
  {
    /* Clearing screen buffer */
    memset(R,XPAL(0),160);
    /* Clearing Z-buffer */
    memset(Z,0x00,22);
    memset(Z+22,0x00,22);
  }
  else
  {
    Offset=Y+SCROLLY;
    T=BgdTab+((int)(Offset&0xF8)<<2);
    Offset=(Offset&0x07)<<1;

    shift=SCROLLX&0x07;
    R-=shift;
    X1=SCROLLX>>3;
    Z[0]=Z[22]=0;

    /* Determine how much background is shown */
    X2=(WNDPOSX>7)? WNDPOSX-7:0;
    if((~LCDCONT&0x20)||(WNDPOSY>Y)||(X2>159)) X2=160;
    X2=X1+((X2+7)>>3);

    for(;X1<=X2;X1++)
    {
      D0=*(T+(X1&0x1F));
      if(~LCDCONT&0x10) D0+=0x80;
      P=ChrGen+(D0<<4)+Offset;
      D0=*P;

      /* Modifying Z-buffer */
      D1=(int)(D0|*(P+1))<<shift;
      Z[0]|=D1>>8;
      Z[1]=D1&0xFF;
      Z[22]=0x00;
      ++Z;

      /* Modifying screen buffer */
      D1=(int)*(P+1)<<1;
      D1=(D1&0xAAA)|((D1&0x555)<<7)|(D0&0x55)|((int)(D0&0xAA)<<7);
      R[0]=PAL((D1&0xC000)>>14);
      R[1]=PAL((D1&0x00C0)>>6 );
      R[2]=PAL((D1&0x3000)>>12);
      R[3]=PAL((D1&0x0030)>>4 );
      R[4]=PAL((D1&0x0C00)>>10);
      R[5]=PAL((D1&0x000C)>>2 );
      R[6]=PAL((D1&0x0300)>>8 );
      R[7]=PAL( D1&0x003      );

      /* Moving pointers */
      R+=8;
    }
  }

  X1=(WNDPOSX>7)? WNDPOSX-7:0;
  if(((LCDCONT&0xA0)==0xA0)&&(WNDPOSY<=Y)&&(X1<160))
  {
    R=X+X1;
    Z=ZBuf+X1/8+1;
    Offset=Y-WNDPOSY;
    T=WndTab+((int)(Offset&0xF8)<<2);
    Offset=(Offset&0x07)<<1;

    D0=0xFF>>(X1&0x07);
    if(LCDCONT&0x02) Z[22]=Z0=0x00;
    else { Z[22]=D0;Z0=0xFF; }
    Z[0]|=D0;Z++;

    for(X1>>=3;X1<(160>>3);X1++)
    {
      D0=*(T++)+0x80;
      P=RAM+0x8800+((int)D0<<4)+Offset;

      /* Modifying Z-buffer */
      Z[22]=Z0;Z[0]=0xFF;++Z;

      /* Modifying screen buffer */
      D0=*P;D1=(int)*(P+1)<<1;
      D1=(D1&0xAAA)|((D1&0x555)<<7)|(D0&0x55)|((int)(D0&0xAA)<<7);
      R[0]=WPAL((D1&0xC000)>>14);
      R[1]=WPAL((D1&0x00C0)>>6 );
      R[2]=WPAL((D1&0x3000)>>12);
      R[3]=WPAL((D1&0x0030)>>4 );
      R[4]=WPAL((D1&0x0C00)>>10);
      R[5]=WPAL((D1&0x000C)>>2 );
      R[6]=WPAL((D1&0x0300)>>8 );
      R[7]=WPAL( D1&0x0003     );

      /* Moving pointers */
      R+=8;
    }
  }
 if (!(LCDCONT&0x80)) return;

 /* Refresh sprites */
#undef PAL
#ifdef USE_XPAL
#define PAL(N) Pal[N]
#else
#define PAL(N) R[N]+4
#endif

  N=LCDCONT&0x04? 16:8;
  for(S=RAM+0xFE9C;S>RAM+0xFE9C-40*4;S-=4)
  {
    if(Y>=(S[0]-16)&&Y<(S[0]-16+N)&&S[1]&&(S[1]<168))
    {
      shift=S[1]-(S[3]&0x20? 1:8);
      P=X+shift;
      Z=ZBuf+shift/8+1;
      /* Only clip to window if priority flag is set */
      if ((S[3]&0x80)==0) Z+=22;
      shift&=7;
      T=RAM+0x8000+(((N>8)? S[2]&0xFE:S[2])<<4);
      if(S[3]&0x40)
       T+=(N-1-Y+S[0]-16)*2;
      else
       T+=(Y-S[0]+16)*2;
      R=S[3]&0x10? SPal1:SPal0;
#ifdef USE_XPAL
      Pal[0]=(XPal+4)[R[0]];Pal[1]=(XPal+4)[R[1]];
      Pal[2]=(XPal+4)[R[2]];Pal[3]=(XPal+4)[R[3]];
#endif
      if(S[3]&0x20)
      {
        shift=7-shift;
        D0=*T;D1=*(T+1);K=D0|D1;D1<<=1;
        D1=(D1&0xAAA)|((D1&0x555)<<7)|(D0&0x55)|((unsigned)(D0&0xAA)<<7);
        K&=spriteconv[((Z[-1]*256+Z[0])>>shift)&0xFF];
        if(K&0x80) P[0]=PAL((D1&0xC000)>>14);
        if(K&0x40) P[-1]=PAL((D1&0x00C0)>>6 );
        if(K&0x20) P[-2]=PAL((D1&0x3000)>>12);
        if(K&0x10) P[-3]=PAL((D1&0x0030)>>4 );
        if(K&0x08) P[-4]=PAL((D1&0x0C00)>>10);
        if(K&0x04) P[-5]=PAL((D1&0x000C)>>2 );
        if(K&0x02) P[-6]=PAL((D1&0x0300)>>8 );
        if(K&0x01) P[-7]=PAL( D1&0x0003     );
      }
      else
      {
        shift=8-shift;
        D0=*T;D1=*(T+1);K=D0|D1;D1<<=1;
        D1=(D1&0xAAA)|((D1&0x555)<<7)|(D0&0x55)|((unsigned)(D0&0xAA)<<7);
        K&=~((Z[0]*256+Z[1])>>shift);
        if(K&0x80) P[0]=PAL((D1&0xC000)>>14);
        if(K&0x40) P[1]=PAL((D1&0x00C0)>>6 );
        if(K&0x20) P[2]=PAL((D1&0x3000)>>12);
        if(K&0x10) P[3]=PAL((D1&0x0030)>>4 );
        if(K&0x08) P[4]=PAL((D1&0x0C00)>>10);
        if(K&0x04) P[5]=PAL((D1&0x000C)>>2 );
        if(K&0x02) P[6]=PAL((D1&0x0300)>>8 );
        if(K&0x01) P[7]=PAL( D1&0x0003     );
      }
    }
  }
}

/****************************************************************/
/*** Display the screen buffer.                               ***/
/****************************************************************/
void RefreshScreen() { PutImage(); }