ftcimage.h

一个Xpdf应用的例子

/***************************************************************************/
/*                                                                         */
/*  ftcimage.h                                                             */
/*                                                                         */
/*    FreeType Image cache (specification).                                */
/*                                                                         */
/*  Copyright 2000-2001 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.                                        */
/*                                                                         */
/***************************************************************************/


  /*************************************************************************/
  /*                                                                       */
  /* Each image cache really manages FT_Glyph objects.                     */
  /*                                                                       */
  /*************************************************************************/


#ifndef __FTCIMAGE_H__
#define __FTCIMAGE_H__


#include <ft2build.h>
#include FT_CACHE_H


FT_BEGIN_HEADER


  /*************************************************************************/
  /*                                                                       */
  /* <Section>                                                             */
  /*    cache_subsystem                                                    */
  /*                                                                       */
  /*************************************************************************/


  /*************************************************************************/
  /*************************************************************************/
  /*************************************************************************/
  /*****                                                               *****/
  /*****                       IMAGE CACHE OBJECT                      *****/
  /*****                                                               *****/
  /*************************************************************************/
  /*************************************************************************/
  /*************************************************************************/


#define FTC_IMAGE_FORMAT( x )  ( (x) & 7 )


#define ftc_image_format_bitmap    0x0000
#define ftc_image_format_outline   0x0001

#define ftc_image_format_mask      0x000F

#define ftc_image_flag_monochrome  0x0010
#define ftc_image_flag_unhinted    0x0020
#define ftc_image_flag_autohinted  0x0040
#define ftc_image_flag_unscaled    0x0080
#define ftc_image_flag_no_sbits    0x0100

  /* monochrome bitmap */
#define ftc_image_mono             ftc_image_format_bitmap | \
                                   ftc_image_flag_monochrome

  /* anti-aliased bitmap */
#define ftc_image_grays            ftc_image_format_bitmap

  /* scaled outline */
#define ftc_image_outline          ftc_image_format_outline


  /*************************************************************************/
  /*                                                                       */
  /* <Struct>                                                              */
  /*    FTC_ImageDesc                                                      */
  /*                                                                       */
  /* <Description>                                                         */
  /*    A simple structure used to describe a given glyph image category.  */
  /*    Note that this is different from @FTC_Image_Desc.                  */
  /*                                                                       */
  /* <Fields>                                                              */
  /*    size    :: An @FTC_SizeRec used to describe the glyph's face and   */
  /*               size.                                                   */
  /*                                                                       */
  /*    type    :: The glyph image's type.  Note that it is a 32-bit uint. */
  /*                                                                       */
  /* <Note>                                                                */
  /*    This type deprecates @FTC_Image_Desc.                              */
  /*                                                                       */
  typedef struct  FTC_ImageDesc_
  {
    FTC_FontRec  font;
    FT_UInt32    type;

  } FTC_ImageDesc;

 /* */

#define FTC_IMAGE_DESC_COMPARE( d1, d2 )                    \
          ( FTC_FONT_COMPARE( &(d1)->font, &(d2)->font ) && \
            (d1)->type == (d2)->type                     )

#define FTC_IMAGE_DESC_HASH( d )                    \
          (FT_UFast)( FTC_FONT_HASH( &(d)->font ) ^ \
                      ( (d)->type << 4 )          )


  /*************************************************************************/
  /*                                                                       */
  /* <Type>                                                                */
  /*    FTC_ImageCache                                                     */
  /*                                                                       */
  /* <Description>                                                         */
  /*    A handle to an glyph image cache object.  They are designed to     */
  /*    hold many distinct glyph images while not exceeding a certain      */
  /*    memory threshold.                                                  */
  /*                                                                       */
  typedef struct FTC_ImageCacheRec_*  FTC_ImageCache;


  /*************************************************************************/
  /*                                                                       */
  /* <Function>                                                            */
  /*    FTC_ImageCache_New                                                 */
  /*                                                                       */
  /* <Description>                                                         */
  /*    Creates a new glyph image cache.                                   */
  /*                                                                       */
  /* <Input>                                                               */
  /*    manager :: The parent manager for the image cache.                 */
  /*                                                                       */
  /* <Output>                                                              */
  /*    acache  :: A handle to the new glyph image cache object.           */
  /*                                                                       */
  /* <Return>                                                              */
  /*    FreeType error code.  0 means success.                             */
  /*                                                                       */
  FT_EXPORT( FT_Error )
  FTC_ImageCache_New( FTC_Manager      manager,
                      FTC_ImageCache  *acache );


  /*************************************************************************/
  /*                                                                       */
  /* <Function>                                                            */
  /*    FTC_ImageCache_Lookup                                              */
  /*                                                                       */