text: /***************************************************************************/
  /*                                                                         */
  /*  ftsmooth.c                                                             */
  /*                                                                         */
  /*    Anti-aliasing renderer interface (body).                             */
  /*                                                                         */
  /*  Copyright 2000-2006, 2009-2012 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_INTERNAL_DEBUG_H
  #include FT_INTERNAL_OBJECTS_H
  #include FT_OUTLINE_H
  #include "ftsmooth.h"
  #include "ftgrays.h"
  #include "ftspic.h"
  
  #include "ftsmerrs.h"
  
  
    /* initialize renderer -- init its raster */
    static FT_Error
    ft_smooth_init( FT_Renderer  render )
    {
      FT_Library  library = FT_MODULE_LIBRARY( render );
  
  
      render->clazz->raster_class->raster_reset( render->raster,
                                                 library->raster_pool,
                                                 library->raster_pool_size );
  
      return 0;
    }
  
  
    /* sets render-specific mode */
    static FT_Error
    ft_smooth_set_mode( FT_Renderer  render,
                        FT_ULong     mode_tag,
                        FT_Pointer   data )
    {
      /* we simply pass it to the raster */
      return render->clazz->raster_class->raster_set_mode( render->raster,
                                                           mode_tag,
                                                           data );
    }
  
    /* transform a given glyph image */
    static FT_Error
    ft_smooth_transform( FT_Renderer       render,
                         FT_GlyphSlot      slot,
                         const FT_Matrix*  matrix,
                         const FT_Vector*  delta )
    {
      FT_Error  error = Smooth_Err_Ok;
  
  
      if ( slot->format != render->glyph_format )
      {
        error = Smooth_Err_Invalid_Argument;
        goto Exit;
      }
  
      if ( matrix )
        FT_Outline_Transform( &slot->outline, matrix );
  
      if ( delta )
        FT_Outline_Translate( &slot->outline, delta->x, delta->y );
  
    Exit:
      return error;
    }
  
  
    /* return the glyph's control box */
    static void
    ft_smooth_get_cbox( FT_Renderer   render,
                        FT_GlyphSlot  slot,
                        FT_BBox*      cbox )
    {
      FT_MEM_ZERO( cbox, sizeof ( *cbox ) );
  
      if ( slot->format == render->glyph_format )
        FT_Outline_Get_CBox( &slot->outline, cbox );
    }
  
  
    /* convert a slot's glyph image into a bitmap */
    static FT_Error
    ft_smooth_render_generic( FT_Renderer       render,
                              FT_GlyphSlot      slot,
                              FT_Render_Mode    mode,
                              const FT_Vector*  origin,
                              FT_Render_Mode    required_mode )
    {
      FT_Error     error;
      FT_Outline*  outline = NULL;
      FT_BBox      cbox;
      FT_Pos       width, height, pitch;
  #ifndef FT_CONFIG_OPTION_SUBPIXEL_RENDERING
      FT_Pos       height_org, width_org;
  #endif
      FT_Bitmap*   bitmap;
      FT_Memory    memory;
      FT_Int       hmul = mode == FT_RENDER_MODE_LCD;
      FT_Int       vmul = mode == FT_RENDER_MODE_LCD_V;
      FT_Pos       x_shift, y_shift, x_left, y_top;
  
      FT_Raster_Params  params;
  
  
      /* check glyph image format */
      if ( slot->format != render->glyph_format )
      {
        error = Smooth_Err_Invalid_Argument;
        goto Exit;
      }
  
      /* check mode */
      if ( mode != required_mode )
        return Smooth_Err_Cannot_Render_Glyph;
  
      outline = &slot->outline;
  
      /* translate the outline to the new origin if needed */
      if ( origin )
        FT_Outline_Translate( outline, origin->x, origin->y );
  
      /* compute the control box, and grid fit it */
      FT_Outline_Get_CBox( outline, &cbox );
  
      cbox.xMin = FT_PIX_FLOOR( cbox.xMin );
      cbox.yMin = FT_PIX_FLOOR( cbox.yMin );
      cbox.xMax = FT_PIX_CEIL( cbox.xMax );
      cbox.yMax = FT_PIX_CEIL( cbox.yMax );
  
      if ( cbox.xMin < 0 && cbox.xMax > FT_INT_MAX + cbox.xMin )
      {
        FT_ERROR(( "ft_smooth_render_generic: glyph too large:"
                   " xMin = %d, xMax = %d\n",
                   cbox.xMin >> 6, cbox.xMax >> 6 ));
        return Smooth_Err_Raster_Overflow;
      }
      else
        width  = ( cbox.xMax - cbox.xMin ) >> 6;
  
      if ( cbox.yMin < 0 && cbox.yMax > FT_INT_MAX + cbox.yMin )
      {
        FT_ERROR(( "ft_smooth_render_generic: glyph too large:"
                   " yMin = %d, yMax = %d\n",
                   cbox.yMin >> 6, cbox.yMax >> 6 ));
        return Smooth_Err_Raster_Overflow;
      }
      else
        height = ( cbox.yMax - cbox.yMin ) >> 6;
  
      bitmap = &slot->bitmap;
      memory = render->root.memory;
  
  #ifndef FT_CONFIG_OPTION_SUBPIXEL_RENDERING
      width_org  = width;
      height_org = height;
  #endif
  
      /* release old bitmap buffer */
      if ( slot->internal->flags & FT_GLYPH_OWN_BITMAP )
      {
        FT_FREE( bitmap->buffer );
        slot->internal->flags &= ~FT_GLYPH_OWN_BITMAP;
      }
  
      /* allocate new one */
      pitch = width;
      if ( hmul )
      {
        width = width * 3;
        pitch = FT_PAD_CEIL( width, 4 );
      }
  
      if ( vmul )
        height *= 3;
  
      x_shift = (FT_Int) cbox.xMin;
      y_shift = (FT_Int) cbox.yMin;
      x_left  = (FT_Int)( cbox.xMin >> 6 );
      y_top   = (FT_Int)( cbox.yMax >> 6 );
  
  #ifdef FT_CONFIG_OPTION_SUBPIXEL_RENDERING
  
      if ( slot->library->lcd_filter_func )
      {
        FT_Int  extra = slot->library->lcd_extra;
  
  
        if ( hmul )
        {
          x_shift -= 64 * ( extra >> 1 );
          width   += 3 * extra;
          pitch    = FT_PAD_CEIL( width, 4 );
          x_left  -= extra >> 1;
        }
  
        if ( vmul )
        {
          y_shift -= 64 * ( extra >> 1 );
          height  += 3 * extra;
          y_top   += extra >> 1;
        }
      }
  
  #endif
  
  #if FT_UINT_MAX > 0xFFFFU
  
      /* Required check is ( pitch * height < FT_ULONG_MAX ),     */
      /* but we care realistic cases only. Always pitch <= width. */
      if ( width > 0x7FFF || height > 0x7FFF )
      {
        FT_ERROR(( "ft_smooth_render_generic: glyph too large: %u x %u\n",
                   width, height ));
        return Smooth_Err_Raster_Overflow;
      }
  
  #endif
  
      bitmap->pixel_mode = FT_PIXEL_MODE_GRAY;
      bitmap->num_grays  = 256;
      bitmap->width      = width;
      bitmap->rows       = height;
      bitmap->pitch      = pitch;
  
      /* translate outline to render it into the bitmap */
      FT_Outline_Translate( outline, -x_shift, -y_shift );
  
      if ( FT_ALLOC( bitmap->buffer, (FT_ULong)pitch * height ) )
        goto Exit;
  
      slot->internal->flags |= FT_GLYPH_OWN_BITMAP;
  
      /* set up parameters */
      params.target = bitmap;
      params.source = outline;
      params.flags  = FT_RASTER_FLAG_AA;
  
  #ifdef FT_CONFIG_OPTION_SUBPIXEL_RENDERING
  
      /* implode outline if needed */
      {
        FT_Vector*  points     = outline->points;
        FT_Vector*  points_end = points + outline->n_points;
        FT_Vector*  vec;
  
  
        if ( hmul )
          for ( vec = points; vec < points_end; vec++ )
            vec->x *= 3;
  
        if ( vmul )
          for ( vec = points; vec < points_end; vec++ )
            vec->y *= 3;
      }
  
      /* render outline into the bitmap */
      error = render->raster_render( render->raster, &params );
  
      /* deflate outline if needed */
      {
        FT_Vector*  points     = outline->points;
        FT_Vector*  points_end = points + outline->n_points;
        FT_Vector*  vec;
  
  
        if ( hmul )
          for ( vec = points; vec < points_end; vec++ )
            vec->x /= 3;
  
        if ( vmul )
          for ( vec = points; vec < points_end; vec++ )
            vec->y /= 3;
      }
  
      if ( slot->library->lcd_filter_func )
        slot->library->lcd_filter_func( bitmap, mode, slot->library );
  
  #else /* !FT_CONFIG_OPTION_SUBPIXEL_RENDERING */
  
      /* render outline into bitmap */
      error = render->raster_render( render->raster, &params );
  
      /* expand it horizontally */
      if ( hmul )
      {
        FT_Byte*  line = bitmap->buffer;
        FT_UInt   hh;
  
  
        for ( hh = height_org; hh > 0; hh--, line += pitch )
        {
          FT_UInt   xx;
          FT_Byte*  end = line + width;
  
  
          for ( xx = width_org; xx > 0; xx-- )
          {
            FT_UInt  pixel = line[xx-1];
  
  
            end[-3] = (FT_Byte)pixel;
            end[-2] = (FT_Byte)pixel;
            end[-1] = (FT_Byte)pixel;
            end    -= 3;
          }
        }
      }
  
      /* expand it vertically */
      if ( vmul )
      {
        FT_Byte*  read  = bitmap->buffer + ( height - height_org ) * pitch;
        FT_Byte*  write = bitmap->buffer;
        FT_UInt   hh;
  
  
        for ( hh = height_org; hh > 0; hh-- )
        {
          ft_memcpy( write, read, pitch );
          write += pitch;
  
          ft_memcpy( write, read, pitch );
          write += pitch;
  
          ft_memcpy( write, read, pitch );
          write += pitch;
          read  += pitch;
        }
      }
  
  #endif /* !FT_CONFIG_OPTION_SUBPIXEL_RENDERING */
  
      FT_Outline_Translate( outline, x_shift, y_shift );
  
      /*
       * XXX: on 16bit system, we return an error for huge bitmap
       * to prevent an overflow.
       */
      if ( x_left > FT_INT_MAX || y_top > FT_INT_MAX )
        return Smooth_Err_Invalid_Pixel_Size;
  
      if ( error )
        goto Exit;
  
      slot->format      = FT_GLYPH_FORMAT_BITMAP;
      slot->bitmap_left = (FT_Int)x_left;
      slot->bitmap_top  = (FT_Int)y_top;
  
    Exit:
      if ( outline && origin )
        FT_Outline_Translate( outline, -origin->x, -origin->y );
  
      return error;
    }
  
  
    /* convert a slot's glyph image into a bitmap */
    static FT_Error
    ft_smooth_render( FT_Renderer       render,
                      FT_GlyphSlot      slot,
                      FT_Render_Mode    mode,
                      const FT_Vector*  origin )
    {
      if ( mode == FT_RENDER_MODE_LIGHT )
        mode = FT_RENDER_MODE_NORMAL;
  
      return ft_smooth_render_generic( render, slot, mode, origin,
                                       FT_RENDER_MODE_NORMAL );
    }
  
  
    /* convert a slot's glyph image into a horizontal LCD bitmap */
    static FT_Error
    ft_smooth_render_lcd( FT_Renderer       render,
                          FT_GlyphSlot      slot,
                          FT_Render_Mode    mode,
                          const FT_Vector*  origin )
    {
      FT_Error  error;
  
      error = ft_smooth_render_generic( render, slot, mode, origin,
                                        FT_RENDER_MODE_LCD );
      if ( !error )
        slot->bitmap.pixel_mode = FT_PIXEL_MODE_LCD;
  
      return error;
    }
  
  
    /* convert a slot's glyph image into a vertical LCD bitmap */
    static FT_Error
    ft_smooth_render_lcd_v( FT_Renderer       render,
                            FT_GlyphSlot      slot,
                            FT_Render_Mode    mode,
                            const FT_Vector*  origin )
    {
      FT_Error  error;
  
      error = ft_smooth_render_generic( render, slot, mode, origin,
                                        FT_RENDER_MODE_LCD_V );
      if ( !error )
        slot->bitmap.pixel_mode = FT_PIXEL_MODE_LCD_V;
  
      return error;
    }
  
  
    FT_DEFINE_RENDERER( ft_smooth_renderer_class,
  
        FT_MODULE_RENDERER,
        sizeof ( FT_RendererRec ),
  
        "smooth",
        0x10000L,
        0x20000L,
  
        0,    /* module specific interface */
  
        (FT_Module_Constructor)ft_smooth_init,
        (FT_Module_Destructor) 0,
        (FT_Module_Requester)  0
      ,
  
      FT_GLYPH_FORMAT_OUTLINE,
  
      (FT_Renderer_RenderFunc)   ft_smooth_render,
      (FT_Renderer_TransformFunc)ft_smooth_transform,
      (FT_Renderer_GetCBoxFunc)  ft_smooth_get_cbox,
      (FT_Renderer_SetModeFunc)  ft_smooth_set_mode,
  
      (FT_Raster_Funcs*)    &FT_GRAYS_RASTER_GET
    )
  
  
    FT_DEFINE_RENDERER( ft_smooth_lcd_renderer_class,
  
        FT_MODULE_RENDERER,
        sizeof ( FT_RendererRec ),
  
        "smooth-lcd",
        0x10000L,
        0x20000L,
  
        0,    /* module specific interface */
  
        (FT_Module_Constructor)ft_smooth_init,
        (FT_Module_Destructor) 0,
        (FT_Module_Requester)  0
      ,
  
      FT_GLYPH_FORMAT_OUTLINE,
  
      (FT_Renderer_RenderFunc)   ft_smooth_render_lcd,
      (FT_Renderer_TransformFunc)ft_smooth_transform,
      (FT_Renderer_GetCBoxFunc)  ft_smooth_get_cbox,
      (FT_Renderer_SetModeFunc)  ft_smooth_set_mode,
  
      (FT_Raster_Funcs*)    &FT_GRAYS_RASTER_GET
    )
  
    FT_DEFINE_RENDERER( ft_smooth_lcdv_renderer_class,
  
        FT_MODULE_RENDERER,
        sizeof ( FT_RendererRec ),
  
        "smooth-lcdv",
        0x10000L,
        0x20000L,
  
        0,    /* module specific interface */
  
        (FT_Module_Constructor)ft_smooth_init,
        (FT_Module_Destructor) 0,
        (FT_Module_Requester)  0
      ,
  
      FT_GLYPH_FORMAT_OUTLINE,
  
      (FT_Renderer_RenderFunc)   ft_smooth_render_lcd_v,
      (FT_Renderer_TransformFunc)ft_smooth_transform,
      (FT_Renderer_GetCBoxFunc)  ft_smooth_get_cbox,
      (FT_Renderer_SetModeFunc)  ft_smooth_set_mode,
  
      (FT_Raster_Funcs*)    &FT_GRAYS_RASTER_GET
    )
  
  
  /* END */
  