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/***************************************************************************/

/*                                                                         */

/*  ftgasp.h                                                               */

/*                                                                         */

/*    Access of TrueType's `gasp' table (specification).                   */

/*                                                                         */

/*  Copyright 2007 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.                                        */

/*                                                                         */

/***************************************************************************/

#ifndef _FT_GASP_H_

#define _FT_GASP_H_

#include <ft2build.h>

#include FT_FREETYPE_H

  /***************************************************************************

   *

   * @section:

   *   gasp_table

   *

   * @title:

   *   Gasp Table

   *

   * @abstract:

   *   Retrieving TrueType `gasp' table entries

   *

   * @description:

   *   The function @FT_Get_Gasp can be used to query a TrueType or OpenType

   *   font for specific entries in their `gasp' table, if any.  This is

   *   mainly useful when implementing native TrueType hinting with the

   *   bytecode interpreter to duplicate the Windows text rendering results.

   */

  /*************************************************************************

   *

   * @enum:

   *   FT_GASP_XXX

   *

   * @description:

   *   A list of values and/or bit-flags returned by the @FT_Get_Gasp

   *   function.

   *

   * @values:

   *   FT_GASP_NO_TABLE ::

   *     This special value means that there is no GASP table in this face.

   *     It is up to the client to decide what to do.

   *

   *   FT_GASP_DO_GRIDFIT ::

   *     Grid-fitting and hinting should be performed at the specified ppem.

   *     This *really* means TrueType bytecode interpretation.

   *

   *   FT_GASP_DO_GRAY ::

   *     Anti-aliased rendering should be performed at the specified ppem.

   *

   *   FT_GASP_SYMMETRIC_SMOOTHING ::

   *     Smoothing along multiple axes must be used with ClearType.

   *

   *   FT_GASP_SYMMETRIC_GRIDFIT ::

   *     Grid-fitting must be used with ClearType's symmetric smoothing.

   *

   * @note:

   *   `ClearType' is Microsoft's implementation of LCD rendering, partly

   *   protected by patents.

   *

   * @since:

   *   2.3.0

   */

#define FT_GASP_NO_TABLE               -1

#define FT_GASP_DO_GRIDFIT           0x01

#define FT_GASP_DO_GRAY              0x02

#define FT_GASP_SYMMETRIC_SMOOTHING  0x08

#define FT_GASP_SYMMETRIC_GRIDFIT    0x10

  /*************************************************************************

   *

   * @func:

   *   FT_Get_Gasp

   *

   * @description:

   *   Read the `gasp' table from a TrueType or OpenType font file and

   *   return the entry corresponding to a given character pixel size.

   *

   * @input:

   *   face :: The source face handle.

   *   ppem :: The vertical character pixel size.

   *

   * @return:

   *   Bit flags (see @FT_GASP_XXX), or @FT_GASP_NO_TABLE is there is no

   *   `gasp' table in the face.

   *

   * @since:

   *   2.3.0

   */

  FT_EXPORT( FT_Int )

  FT_Get_Gasp( FT_Face  face,

               FT_UInt  ppem );

/* */

#endif /* _FT_GASP_H_ */

/* END */