ttinterp.c

神龙卡开发原代码

  {
    return (v1->x - v2->x);
  }


/*******************************************************************
 *
 *  Function    :  Project_y
 *
 *  Input  :  Vx, Vy    input vector
 *
 *  Output :  Returns Vy.
 *
 *  Note :    Used as a dummy function.
 *
 *****************************************************************/

  static TT_F26Dot6  Project_y( EXEC_OPS TT_Vector*  v1,
                                         TT_Vector*  v2 )
  {
    return (v1->y - v2->y);
  }


/*******************************************************************
 *
 *  Function    :  Compute_Funcs
 *
 *  Description :  Computes the projections and movement function
 *                 pointers according to the current graphics state.
 *
 *  Input  :  None
 *
 *****************************************************************/

  static void  Compute_Funcs( EXEC_OP )
  {
    if ( CUR.GS.freeVector.x == 0x4000 )
    {
      CUR.func_freeProj = (TProject_Function)Project_x;
      CUR.F_dot_P       = CUR.GS.projVector.x * 0x10000L;
    }
    else
    {
      if ( CUR.GS.freeVector.y == 0x4000 )
      {
        CUR.func_freeProj = (TProject_Function)Project_y;
        CUR.F_dot_P       = CUR.GS.projVector.y * 0x10000L;
      }
      else
      {
        CUR.func_freeProj = (TProject_Function)Free_Project;
        CUR.F_dot_P = (Long)CUR.GS.projVector.x * CUR.GS.freeVector.x * 4 +
                      (Long)CUR.GS.projVector.y * CUR.GS.freeVector.y * 4;
      }
    }

    CUR.cached_metrics = FALSE;

    if ( CUR.GS.projVector.x == 0x4000 )
      CUR.func_project = (TProject_Function)Project_x;
    else
    {
      if ( CUR.GS.projVector.y == 0x4000 )
        CUR.func_project = (TProject_Function)Project_y;
      else
        CUR.func_project = (TProject_Function)Project;
    }

    if ( CUR.GS.dualVector.x == 0x4000 )
      CUR.func_dualproj = (TProject_Function)Project_x;
    else
    {
      if ( CUR.GS.dualVector.y == 0x4000 )
        CUR.func_dualproj = (TProject_Function)Project_y;
      else
        CUR.func_dualproj = (TProject_Function)Dual_Project;
    }

    CUR.func_move = (TMove_Function)Direct_Move;

    if ( CUR.F_dot_P == 0x40000000L )
    {
      if ( CUR.GS.freeVector.x == 0x4000 )
        CUR.func_move = (TMove_Function)Direct_Move_X;
      else
      {
        if ( CUR.GS.freeVector.y == 0x4000 )
          CUR.func_move = (TMove_Function)Direct_Move_Y;
      }
    }

    /* at small sizes, F_dot_P can become too small, resulting   */
    /* in overflows and 'spikes' in a number of glyphs like 'w'. */

    if ( ABS( CUR.F_dot_P ) < 0x4000000L )
      CUR.F_dot_P = 0x40000000L;

    /* Disable cached aspect ratio */
    CUR.metrics.ratio = 0;
  }


/*******************************************************************
 *
 *  Function    :  Normalize
 *
 *  Description :  Norms a vector
 *
 *  Input  :  Vx, Vy    input vector
 *            R         normed unit vector
 *
 *  Output :  Returns FAILURE if a vector parameter is zero.
 *
 *****************************************************************/

  static Bool  Normalize( EXEC_OPS TT_F26Dot6      Vx,
                                   TT_F26Dot6      Vy,
                                   TT_UnitVector*  R )
  {
    TT_F26Dot6  W;
    Bool        S1, S2;


    if ( ABS( Vx ) < 0x10000L && ABS( Vy ) < 0x10000L )
    {
      Vx *= 0x100;
      Vy *= 0x100;

      W = Norm( Vx, Vy );

      if ( W == 0 )
      {
        /* XXX : UNDOCUMENTED! It seems that it's possible to try  */
        /*       to normalize the vector (0,0). Return immediately */
        return SUCCESS;
      }

      R->x = (TT_F2Dot14)TT_MulDiv( Vx, 0x4000L, W );
      R->y = (TT_F2Dot14)TT_MulDiv( Vy, 0x4000L, W );

      return SUCCESS;
    }

    W = Norm( Vx, Vy );

    Vx = TT_MulDiv( Vx, 0x4000L, W );
    Vy = TT_MulDiv( Vy, 0x4000L, W );

    W = Vx * Vx + Vy * Vy;

    /* Now, we want that Sqrt( W ) = 0x4000 */
    /* Or 0x1000000 <= W < 0x1004000        */

    if ( Vx < 0 )
    {
      Vx = -Vx;
      S1 = TRUE;
    }
    else
      S1 = FALSE;

    if ( Vy < 0 )
    {
      Vy = -Vy;
      S2 = TRUE;
    }
    else
      S2 = FALSE;

    while ( W < 0x1000000L )
    {
      /* We need to increase W, by a minimal amount */
      if ( Vx < Vy )
        Vx++;
      else
        Vy++;

      W = Vx * Vx + Vy * Vy;
    }

    while ( W >= 0x1004000L )
    {
      /* We need to decrease W, by a minimal amount */
      if ( Vx < Vy )
        Vx--;
      else
        Vy--;

      W = Vx * Vx + Vy * Vy;
    }

    /* Note that in various cases, we can only  */
    /* compute a Sqrt(W) of 0x3FFF, eg. Vx = Vy */

    if ( S1 )
      Vx = -Vx;

    if ( S2 )
      Vy = -Vy;

    R->x = (TT_F2Dot14)Vx;   /* Type conversion */
    R->y = (TT_F2Dot14)Vy;   /* Type conversion */

    return SUCCESS;
  }


/****************************************************************
 *
 *  Opcodes
 *
 ****************************************************************/


  static Bool  Ins_SxVTL( EXEC_OPS  UShort          aIdx1,
                                    UShort          aIdx2,
                                    Int             aOpc,
                                    TT_UnitVector*  Vec )
  {
    Long       A, B, C;
    TT_Vector* p1;
    TT_Vector* p2;


    if ( BOUNDS( aIdx1, CUR.zp2.n_points ) ||
         BOUNDS( aIdx2, CUR.zp1.n_points ) )
    {
      if ( CUR.pedantic_hinting )
        CUR.error = TT_Err_Invalid_Reference;
      return FAILURE;
    }

    p1 = CUR.zp1.cur + aIdx2;
    p2 = CUR.zp2.cur + aIdx1;

    A = p1->x - p2->x;
    B = p1->y - p2->y;

    if ( (aOpc & 1) != 0 )
    {
      C =  B;   /* CounterClockwise rotation */
      B =  A;
      A = -C;
    }

    NORMalize( A, B, Vec );
    return SUCCESS;
  }


/* When not using the big switch statements, the interpreter uses a */
/* call table defined later below in this source.  Each opcode must */
/* thus have a corresponding function, even trivial ones.           */
/*                                                                  */
/* They're all defined there.                                       */

#define DO_SVTCA                       \
  {                                    \
    Short  A, B;                       \
                                       \
                                       \
    A = (Short)(CUR.opcode & 1) << 14; \
    B = A ^ (Short)0x4000;             \
                                       \
    CUR.GS.freeVector.x = A;           \
    CUR.GS.projVector.x = A;           \
    CUR.GS.dualVector.x = A;           \
                                       \
    CUR.GS.freeVector.y = B;           \
    CUR.GS.projVector.y = B;           \
    CUR.GS.dualVector.y = B;           \
                                       \
    COMPUTE_Funcs();                   \
  }


#define DO_SPVTCA                      \
  {                                    \
    Short  A, B;                       \
                                       \
                                       \
    A = (Short)(CUR.opcode & 1) << 14; \
    B = A ^ (Short)0x4000;             \
                                       \
    CUR.GS.projVector.x = A;           \
    CUR.GS.dualVector.x = A;           \
                                       \
    CUR.GS.projVector.y = B;           \
    CUR.GS.dualVector.y = B;           \
                                       \
    COMPUTE_Funcs();                   \
  }


#define DO_SFVTCA                      \
  {                                    \
    Short  A, B;                       \
                                       \
                                       \
    A = (Short)(CUR.opcode & 1) << 14; \
    B = A ^ (Short)0x4000;             \
                                       \
    CUR.GS.freeVector.x = A;           \
    CUR.GS.freeVector.y = B;           \
                                       \
    COMPUTE_Funcs();                   \
  }


#define DO_SPVTL                                     \
    if ( INS_SxVTL( (UShort)args[1],                 \
                    (UShort)args[0],                 \
                    CUR.opcode,                      \
                    &CUR.GS.projVector) == SUCCESS ) \
    {                                                \
      CUR.GS.dualVector = CUR.GS.projVector;         \
      COMPUTE_Funcs();                               \
    }


#define DO_SFVTL                                     \
    if ( INS_SxVTL( (UShort)args[1],                 \
                    (UShort)args[0],                 \
                    CUR.opcode,                      \
                    &CUR.GS.freeVector) == SUCCESS ) \
      COMPUTE_Funcs();


#define DO_SFVTPV                          \
    CUR.GS.freeVector = CUR.GS.projVector; \
    COMPUTE_Funcs();


#define DO_SPVFS                                \
  {                                             \
    Short  S;                                   \
    Long   X, Y;                                \
                                                \
                                                \
    /* Only use low 16bits, then sign extend */ \
    S = (Short)args[1];                         \
    Y = (Long)S;                                \
    S = (Short)args[0];                         \
    X = (Long)S;                                \
                                                \
    NORMalize( X, Y, &CUR.GS.projVector );      \
                                                \
    CUR.GS.dualVector = CUR.GS.projVector;      \
    COMPUTE_Funcs();                            \
  }


#define DO_SFVFS                                \
  {                                             \
    Short  S;                                   \
    Long   X, Y;                                \
                                                \
                                                \
    /* Only use low 16bits, then sign extend */ \
    S = (Short)args[1];                         \
    Y = (Long)S;                                \
    S = (Short)args[0];                         \
    X = S;                                      \
                                                \
    NORMalize( X, Y, &CUR.GS.freeVector );      \
    COMPUTE_Funcs();                            \
  }


#define DO_GPV                     \
    args[0] = CUR.GS.projVector.x; \
    args[1] = CUR.GS.projVector.y;


#define DO_GFV                     \
    args[0] = CUR.GS.freeVector.x; \
    args[1] = CUR.GS.freeVector.y;


#define DO_SRP0  \
    CUR.GS.rp0 = (UShort)args[0];


#define DO_SRP1  \
    CUR.GS.rp1 = (UShort)args[0];


#define DO_SRP2  \
    CUR.GS.rp2 = (UShort)args[0];


#define DO_RTHG                                           \
    CUR.GS.round_state = TT_Round_To_Half_Grid;           \
    CUR.func_round = (TRound_Function)Round_To_Half_Grid;


#define DO_RTG                                       \
    CUR.GS.round_state = TT_Round_To_Grid;           \
    CUR.func_round = (TRound_Function)Round_To_Grid;


#define DO_RTDG                                             \
    CUR.GS.round_state = TT_Round_To_Double_Grid;           \
    CUR.func_round = (TRound_Function)Round_To_Double_Grid;


#define DO_RUTG                                         \
    CUR.GS.round_state = TT_Round_Up_To_Grid;           \
    CUR.func_round = (TRound_Function)Round_Up_To_Grid;


#define DO_RDTG                                           \
    CUR.GS.round_state = TT_Round_Down_To_Grid;           \
    CUR.func_round = (TRound_Function)Round_Down_To_Grid;


#define DO_ROFF                                   \
    CUR.GS.round_state = TT_Round_Off;            \
    CUR.func_round = (TRound_Function)Round_None;


#define DO_SROUND                                  \
    SET_SuperRound( 0x4000L, args[0] );            \
    CUR.GS.round_state = TT_Round_Super;           \
    CUR.func_round = (TRound_Function)Round_Super;


#define DO_S45ROUND                                   \
    SET_SuperRound( 0x2D41L, args[0] );               \
    CUR.GS.round_state = TT_Round_Super_45;           \
    CUR.func_round = (TRound_Function)Round_Super_45;


#define DO_SLOOP                       \
    if ( args[0] < 0 )                 \
      CUR.error = TT_Err_Bad_Argument; \
    else                               \
      CUR.GS.loop = args[0];


#define DO_SMD  \
    CUR.GS.minimum_distance = (TT_F26Dot6)args[0];


#define DO_SCVTCI  \
    CUR.GS.control_value_cutin = (TT_F26Dot6)args[0];


#define DO_SSWCI  \
    CUR.GS.single_width_cutin = (TT_F26Dot6)args[0];


    /* XXX : UNDOCUMENTED! or bug in the Windows engine?  */
    /*                                                    */
    /* It seems that the value that is read here is       */
    /* expressed in 16.16 format, rather than in          */
    /* font units..                                       */
    /*                                                    */
#define DO_SSW  \
    CUR.GS.single_width_value = (TT_F26Dot6)(args[0] >> 10);


#define DO_FLIPON  \