misc/libfreetype/src/base/ftbitmap.c
changeset 5172 88f2e05288ba
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/misc/libfreetype/src/base/ftbitmap.c	Mon Apr 25 01:46:54 2011 +0200
@@ -0,0 +1,663 @@
+/***************************************************************************/
+/*                                                                         */
+/*  ftbitmap.c                                                             */
+/*                                                                         */
+/*    FreeType utility functions for bitmaps (body).                       */
+/*                                                                         */
+/*  Copyright 2004, 2005, 2006, 2007, 2008, 2009 by                        */
+/*  David Turner, Robert Wilhelm, and Werner Lemberg.                      */
+/*                                                                         */
+/*  This file is part of the FreeType project, and may only be used,       */
+/*  modified, and distributed under the terms of the FreeType project      */
+/*  license, LICENSE.TXT.  By continuing to use, modify, or distribute     */
+/*  this file you indicate that you have read the license and              */
+/*  understand and accept it fully.                                        */
+/*                                                                         */
+/***************************************************************************/
+
+
+#include <ft2build.h>
+#include FT_BITMAP_H
+#include FT_IMAGE_H
+#include FT_INTERNAL_OBJECTS_H
+
+
+  static
+  const FT_Bitmap  null_bitmap = { 0, 0, 0, 0, 0, 0, 0, 0 };
+
+
+  /* documentation is in ftbitmap.h */
+
+  FT_EXPORT_DEF( void )
+  FT_Bitmap_New( FT_Bitmap  *abitmap )
+  {
+    *abitmap = null_bitmap;
+  }
+
+
+  /* documentation is in ftbitmap.h */
+
+  FT_EXPORT_DEF( FT_Error )
+  FT_Bitmap_Copy( FT_Library        library,
+                  const FT_Bitmap  *source,
+                  FT_Bitmap        *target)
+  {
+    FT_Memory  memory = library->memory;
+    FT_Error   error  = FT_Err_Ok;
+    FT_Int     pitch  = source->pitch;
+    FT_ULong   size;
+
+
+    if ( source == target )
+      return FT_Err_Ok;
+
+    if ( source->buffer == NULL )
+    {
+      *target = *source;
+
+      return FT_Err_Ok;
+    }
+
+    if ( pitch < 0 )
+      pitch = -pitch;
+    size = (FT_ULong)( pitch * source->rows );
+
+    if ( target->buffer )
+    {
+      FT_Int    target_pitch = target->pitch;
+      FT_ULong  target_size;
+
+
+      if ( target_pitch < 0  )
+        target_pitch = -target_pitch;
+      target_size = (FT_ULong)( target_pitch * target->rows );
+
+      if ( target_size != size )
+        (void)FT_QREALLOC( target->buffer, target_size, size );
+    }
+    else
+      (void)FT_QALLOC( target->buffer, size );
+
+    if ( !error )
+    {
+      unsigned char *p;
+
+
+      p = target->buffer;
+      *target = *source;
+      target->buffer = p;
+
+      FT_MEM_COPY( target->buffer, source->buffer, size );
+    }
+
+    return error;
+  }
+
+
+  static FT_Error
+  ft_bitmap_assure_buffer( FT_Memory   memory,
+                           FT_Bitmap*  bitmap,
+                           FT_UInt     xpixels,
+                           FT_UInt     ypixels )
+  {
+    FT_Error        error;
+    int             pitch;
+    int             new_pitch;
+    FT_UInt         bpp;
+    FT_Int          i, width, height;
+    unsigned char*  buffer;
+
+
+    width  = bitmap->width;
+    height = bitmap->rows;
+    pitch  = bitmap->pitch;
+    if ( pitch < 0 )
+      pitch = -pitch;
+
+    switch ( bitmap->pixel_mode )
+    {
+    case FT_PIXEL_MODE_MONO:
+      bpp       = 1;
+      new_pitch = ( width + xpixels + 7 ) >> 3;
+      break;
+    case FT_PIXEL_MODE_GRAY2:
+      bpp       = 2;
+      new_pitch = ( width + xpixels + 3 ) >> 2;
+      break;
+    case FT_PIXEL_MODE_GRAY4:
+      bpp       = 4;
+      new_pitch = ( width + xpixels + 1 ) >> 1;
+      break;
+    case FT_PIXEL_MODE_GRAY:
+    case FT_PIXEL_MODE_LCD:
+    case FT_PIXEL_MODE_LCD_V:
+      bpp       = 8;
+      new_pitch = ( width + xpixels );
+      break;
+    default:
+      return FT_Err_Invalid_Glyph_Format;
+    }
+
+    /* if no need to allocate memory */
+    if ( ypixels == 0 && new_pitch <= pitch )
+    {
+      /* zero the padding */
+      FT_Int  bit_width = pitch * 8;
+      FT_Int  bit_last  = ( width + xpixels ) * bpp;
+
+
+      if ( bit_last < bit_width )
+      {
+        FT_Byte*  line  = bitmap->buffer + ( bit_last >> 3 );
+        FT_Byte*  end   = bitmap->buffer + pitch;
+        FT_Int    shift = bit_last & 7;
+        FT_UInt   mask  = 0xFF00U >> shift;
+        FT_Int    count = height;
+
+
+        for ( ; count > 0; count--, line += pitch, end += pitch )
+        {
+          FT_Byte*  write = line;
+
+
+          if ( shift > 0 )
+          {
+            write[0] = (FT_Byte)( write[0] & mask );
+            write++;
+          }
+          if ( write < end )
+            FT_MEM_ZERO( write, end-write );
+        }
+      }
+
+      return FT_Err_Ok;
+    }
+
+    if ( FT_QALLOC_MULT( buffer, new_pitch, bitmap->rows + ypixels ) )
+      return error;
+
+    if ( bitmap->pitch > 0 )
+    {
+      FT_Int  len = ( width * bpp + 7 ) >> 3;
+
+
+      for ( i = 0; i < bitmap->rows; i++ )
+        FT_MEM_COPY( buffer + new_pitch * ( ypixels + i ),
+                     bitmap->buffer + pitch * i, len );
+    }
+    else
+    {
+      FT_Int  len = ( width * bpp + 7 ) >> 3;
+
+
+      for ( i = 0; i < bitmap->rows; i++ )
+        FT_MEM_COPY( buffer + new_pitch * i,
+                     bitmap->buffer + pitch * i, len );
+    }
+
+    FT_FREE( bitmap->buffer );
+    bitmap->buffer = buffer;
+
+    if ( bitmap->pitch < 0 )
+      new_pitch = -new_pitch;
+
+    /* set pitch only, width and height are left untouched */
+    bitmap->pitch = new_pitch;
+
+    return FT_Err_Ok;
+  }
+
+
+  /* documentation is in ftbitmap.h */
+
+  FT_EXPORT_DEF( FT_Error )
+  FT_Bitmap_Embolden( FT_Library  library,
+                      FT_Bitmap*  bitmap,
+                      FT_Pos      xStrength,
+                      FT_Pos      yStrength )
+  {
+    FT_Error        error;
+    unsigned char*  p;
+    FT_Int          i, x, y, pitch;
+    FT_Int          xstr, ystr;
+
+
+    if ( !library )
+      return FT_Err_Invalid_Library_Handle;
+
+    if ( !bitmap || !bitmap->buffer )
+      return FT_Err_Invalid_Argument;
+
+    if ( ( ( FT_PIX_ROUND( xStrength ) >> 6 ) > FT_INT_MAX ) ||
+         ( ( FT_PIX_ROUND( yStrength ) >> 6 ) > FT_INT_MAX ) )
+      return FT_Err_Invalid_Argument;
+       
+    xstr = (FT_Int)FT_PIX_ROUND( xStrength ) >> 6;
+    ystr = (FT_Int)FT_PIX_ROUND( yStrength ) >> 6;
+
+    if ( xstr == 0 && ystr == 0 )
+      return FT_Err_Ok;
+    else if ( xstr < 0 || ystr < 0 )
+      return FT_Err_Invalid_Argument;
+
+    switch ( bitmap->pixel_mode )
+    {
+    case FT_PIXEL_MODE_GRAY2:
+    case FT_PIXEL_MODE_GRAY4:
+      {
+        FT_Bitmap  tmp;
+        FT_Int     align;
+
+
+        if ( bitmap->pixel_mode == FT_PIXEL_MODE_GRAY2 )
+          align = ( bitmap->width + xstr + 3 ) / 4;
+        else
+          align = ( bitmap->width + xstr + 1 ) / 2;
+
+        FT_Bitmap_New( &tmp );
+
+        error = FT_Bitmap_Convert( library, bitmap, &tmp, align );
+        if ( error )
+          return error;
+
+        FT_Bitmap_Done( library, bitmap );
+        *bitmap = tmp;
+      }
+      break;
+
+    case FT_PIXEL_MODE_MONO:
+      if ( xstr > 8 )
+        xstr = 8;
+      break;
+
+    case FT_PIXEL_MODE_LCD:
+      xstr *= 3;
+      break;
+
+    case FT_PIXEL_MODE_LCD_V:
+      ystr *= 3;
+      break;
+    }
+
+    error = ft_bitmap_assure_buffer( library->memory, bitmap, xstr, ystr );
+    if ( error )
+      return error;
+
+    pitch = bitmap->pitch;
+    if ( pitch > 0 )
+      p = bitmap->buffer + pitch * ystr;
+    else
+    {
+      pitch = -pitch;
+      p = bitmap->buffer + pitch * ( bitmap->rows - 1 );
+    }
+
+    /* for each row */
+    for ( y = 0; y < bitmap->rows ; y++ )
+    {
+      /*
+       * Horizontally:
+       *
+       * From the last pixel on, make each pixel or'ed with the
+       * `xstr' pixels before it.
+       */
+      for ( x = pitch - 1; x >= 0; x-- )
+      {
+        unsigned char tmp;
+
+
+        tmp = p[x];
+        for ( i = 1; i <= xstr; i++ )
+        {
+          if ( bitmap->pixel_mode == FT_PIXEL_MODE_MONO )
+          {
+            p[x] |= tmp >> i;
+
+            /* the maximum value of 8 for `xstr' comes from here */
+            if ( x > 0 )
+              p[x] |= p[x - 1] << ( 8 - i );
+
+#if 0
+            if ( p[x] == 0xff )
+              break;
+#endif
+          }
+          else
+          {
+            if ( x - i >= 0 )
+            {
+              if ( p[x] + p[x - i] > bitmap->num_grays - 1 )
+              {
+                p[x] = (unsigned char)(bitmap->num_grays - 1);
+                break;
+              }
+              else
+              {
+                p[x] = (unsigned char)(p[x] + p[x-i]);
+                if ( p[x] == bitmap->num_grays - 1 )
+                  break;
+              }
+            }
+            else
+              break;
+          }
+        }
+      }
+
+      /*
+       * Vertically:
+       *
+       * Make the above `ystr' rows or'ed with it.
+       */
+      for ( x = 1; x <= ystr; x++ )
+      {
+        unsigned char*  q;
+
+
+        q = p - bitmap->pitch * x;
+        for ( i = 0; i < pitch; i++ )
+          q[i] |= p[i];
+      }
+
+      p += bitmap->pitch;
+    }
+
+    bitmap->width += xstr;
+    bitmap->rows += ystr;
+
+    return FT_Err_Ok;
+  }
+
+
+  /* documentation is in ftbitmap.h */
+
+  FT_EXPORT_DEF( FT_Error )
+  FT_Bitmap_Convert( FT_Library        library,
+                     const FT_Bitmap  *source,
+                     FT_Bitmap        *target,
+                     FT_Int            alignment )
+  {
+    FT_Error   error = FT_Err_Ok;
+    FT_Memory  memory;
+
+
+    if ( !library )
+      return FT_Err_Invalid_Library_Handle;
+
+    memory = library->memory;
+
+    switch ( source->pixel_mode )
+    {
+    case FT_PIXEL_MODE_MONO:
+    case FT_PIXEL_MODE_GRAY:
+    case FT_PIXEL_MODE_GRAY2:
+    case FT_PIXEL_MODE_GRAY4:
+    case FT_PIXEL_MODE_LCD:
+    case FT_PIXEL_MODE_LCD_V:
+      {
+        FT_Int   pad;
+        FT_Long  old_size;
+
+
+        old_size = target->rows * target->pitch;
+        if ( old_size < 0 )
+          old_size = -old_size;
+
+        target->pixel_mode = FT_PIXEL_MODE_GRAY;
+        target->rows       = source->rows;
+        target->width      = source->width;
+
+        pad = 0;
+        if ( alignment > 0 )
+        {
+          pad = source->width % alignment;
+          if ( pad != 0 )
+            pad = alignment - pad;
+        }
+
+        target->pitch = source->width + pad;
+
+        if ( target->rows * target->pitch > old_size             &&
+             FT_QREALLOC( target->buffer,
+                          old_size, target->rows * target->pitch ) )
+          return error;
+      }
+      break;
+
+    default:
+      error = FT_Err_Invalid_Argument;
+    }
+
+    switch ( source->pixel_mode )
+    {
+    case FT_PIXEL_MODE_MONO:
+      {
+        FT_Byte*  s = source->buffer;
+        FT_Byte*  t = target->buffer;
+        FT_Int    i;
+
+
+        target->num_grays = 2;
+
+        for ( i = source->rows; i > 0; i-- )
+        {
+          FT_Byte*  ss = s;
+          FT_Byte*  tt = t;
+          FT_Int    j;
+
+
+          /* get the full bytes */
+          for ( j = source->width >> 3; j > 0; j-- )
+          {
+            FT_Int  val = ss[0]; /* avoid a byte->int cast on each line */
+
+
+            tt[0] = (FT_Byte)( ( val & 0x80 ) >> 7 );
+            tt[1] = (FT_Byte)( ( val & 0x40 ) >> 6 );
+            tt[2] = (FT_Byte)( ( val & 0x20 ) >> 5 );
+            tt[3] = (FT_Byte)( ( val & 0x10 ) >> 4 );
+            tt[4] = (FT_Byte)( ( val & 0x08 ) >> 3 );
+            tt[5] = (FT_Byte)( ( val & 0x04 ) >> 2 );
+            tt[6] = (FT_Byte)( ( val & 0x02 ) >> 1 );
+            tt[7] = (FT_Byte)(   val & 0x01 );
+
+            tt += 8;
+            ss += 1;
+          }
+
+          /* get remaining pixels (if any) */
+          j = source->width & 7;
+          if ( j > 0 )
+          {
+            FT_Int  val = *ss;
+
+
+            for ( ; j > 0; j-- )
+            {
+              tt[0] = (FT_Byte)( ( val & 0x80 ) >> 7);
+              val <<= 1;
+              tt   += 1;
+            }
+          }
+
+          s += source->pitch;
+          t += target->pitch;
+        }
+      }
+      break;
+
+
+    case FT_PIXEL_MODE_GRAY:
+    case FT_PIXEL_MODE_LCD:
+    case FT_PIXEL_MODE_LCD_V:
+      {
+        FT_Int    width   = source->width;
+        FT_Byte*  s       = source->buffer;
+        FT_Byte*  t       = target->buffer;
+        FT_Int    s_pitch = source->pitch;
+        FT_Int    t_pitch = target->pitch;
+        FT_Int    i;
+
+
+        target->num_grays = 256;
+
+        for ( i = source->rows; i > 0; i-- )
+        {
+          FT_ARRAY_COPY( t, s, width );
+
+          s += s_pitch;
+          t += t_pitch;
+        }
+      }
+      break;
+
+
+    case FT_PIXEL_MODE_GRAY2:
+      {
+        FT_Byte*  s = source->buffer;
+        FT_Byte*  t = target->buffer;
+        FT_Int    i;
+
+
+        target->num_grays = 4;
+
+        for ( i = source->rows; i > 0; i-- )
+        {
+          FT_Byte*  ss = s;
+          FT_Byte*  tt = t;
+          FT_Int    j;
+
+
+          /* get the full bytes */
+          for ( j = source->width >> 2; j > 0; j-- )
+          {
+            FT_Int  val = ss[0];
+
+
+            tt[0] = (FT_Byte)( ( val & 0xC0 ) >> 6 );
+            tt[1] = (FT_Byte)( ( val & 0x30 ) >> 4 );
+            tt[2] = (FT_Byte)( ( val & 0x0C ) >> 2 );
+            tt[3] = (FT_Byte)( ( val & 0x03 ) );
+
+            ss += 1;
+            tt += 4;
+          }
+
+          j = source->width & 3;
+          if ( j > 0 )
+          {
+            FT_Int  val = ss[0];
+
+
+            for ( ; j > 0; j-- )
+            {
+              tt[0]  = (FT_Byte)( ( val & 0xC0 ) >> 6 );
+              val  <<= 2;
+              tt    += 1;
+            }
+          }
+
+          s += source->pitch;
+          t += target->pitch;
+        }
+      }
+      break;
+
+
+    case FT_PIXEL_MODE_GRAY4:
+      {
+        FT_Byte*  s = source->buffer;
+        FT_Byte*  t = target->buffer;
+        FT_Int    i;
+
+
+        target->num_grays = 16;
+
+        for ( i = source->rows; i > 0; i-- )
+        {
+          FT_Byte*  ss = s;
+          FT_Byte*  tt = t;
+          FT_Int    j;
+
+
+          /* get the full bytes */
+          for ( j = source->width >> 1; j > 0; j-- )
+          {
+            FT_Int  val = ss[0];
+
+
+            tt[0] = (FT_Byte)( ( val & 0xF0 ) >> 4 );
+            tt[1] = (FT_Byte)( ( val & 0x0F ) );
+
+            ss += 1;
+            tt += 2;
+          }
+
+          if ( source->width & 1 )
+            tt[0] = (FT_Byte)( ( ss[0] & 0xF0 ) >> 4 );
+
+          s += source->pitch;
+          t += target->pitch;
+        }
+      }
+      break;
+
+
+    default:
+      ;
+    }
+
+    return error;
+  }
+
+
+  /* documentation is in ftbitmap.h */
+
+  FT_EXPORT_DEF( FT_Error )
+  FT_GlyphSlot_Own_Bitmap( FT_GlyphSlot  slot )
+  {
+    if ( slot && slot->format == FT_GLYPH_FORMAT_BITMAP   &&
+         !( slot->internal->flags & FT_GLYPH_OWN_BITMAP ) )
+    {
+      FT_Bitmap  bitmap;
+      FT_Error   error;
+
+
+      FT_Bitmap_New( &bitmap );
+      error = FT_Bitmap_Copy( slot->library, &slot->bitmap, &bitmap );
+      if ( error )
+        return error;
+
+      slot->bitmap = bitmap;
+      slot->internal->flags |= FT_GLYPH_OWN_BITMAP;
+    }
+
+    return FT_Err_Ok;
+  }
+
+
+  /* documentation is in ftbitmap.h */
+
+  FT_EXPORT_DEF( FT_Error )
+  FT_Bitmap_Done( FT_Library  library,
+                  FT_Bitmap  *bitmap )
+  {
+    FT_Memory  memory;
+
+
+    if ( !library )
+      return FT_Err_Invalid_Library_Handle;
+
+    if ( !bitmap )
+      return FT_Err_Invalid_Argument;
+
+    memory = library->memory;
+
+    FT_FREE( bitmap->buffer );
+    *bitmap = null_bitmap;
+
+    return FT_Err_Ok;
+  }
+
+
+/* END */