/*

 * Copyright © 2010  Red Hat, Inc.

 * Copyright © 2012  Google, Inc.

 *

 *  This is part of HarfBuzz, a text shaping library.

 *

 * Permission is hereby granted, without written agreement and without

 * license or royalty fees, to use, copy, modify, and distribute this

 * software and its documentation for any purpose, provided that the

 * above copyright notice and the following two paragraphs appear in

 * all copies of this software.

 *

 * IN NO EVENT SHALL THE COPYRIGHT HOLDER BE LIABLE TO ANY PARTY FOR

 * DIRECT, INDIRECT, SPECIAL, INCIDENTAL, OR CONSEQUENTIAL DAMAGES

 * ARISING OUT OF THE USE OF THIS SOFTWARE AND ITS DOCUMENTATION, EVEN

 * IF THE COPYRIGHT HOLDER HAS BEEN ADVISED OF THE POSSIBILITY OF SUCH

 * DAMAGE.

 *

 * THE COPYRIGHT HOLDER SPECIFICALLY DISCLAIMS ANY WARRANTIES, INCLUDING,

 * BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND

 * FITNESS FOR A PARTICULAR PURPOSE.  THE SOFTWARE PROVIDED HEREUNDER IS

 * ON AN "AS IS" BASIS, AND THE COPYRIGHT HOLDER HAS NO OBLIGATION TO

 * PROVIDE MAINTENANCE, SUPPORT, UPDATES, ENHANCEMENTS, OR MODIFICATIONS.

 *

 * Red Hat Author(s): Behdad Esfahbod

 * Google Author(s): Behdad Esfahbod

 */

#ifndef HB_OT_HEAD_TABLE_HH

#define HB_OT_HEAD_TABLE_HH

#include "hb-open-type-private.hh"

namespace OT {

/*

 * head -- Font Header

 */

#define HB_OT_TAG_head HB_TAG('h','e','a','d')

struct head

{

  static const hb_tag_t tableTag	= HB_OT_TAG_head;

  inline unsigned int get_upem (void) const

  {

    unsigned int upem = unitsPerEm;

    /* If no valid head table found, assume 1000, which matches typical Type1 usage. */

    return 16 <= upem && upem <= 16384 ? upem : 1000;

  }

  inline bool sanitize (hb_sanitize_context_t *c) const

  {

    TRACE_SANITIZE (this);

    return_trace (c->check_struct (this) &&

		  version.major == 1 &&

		  magicNumber == 0x5F0F3CF5u);

  }

  protected:

  FixedVersion<>version;		/* Version of the head table--currently

					 * 0x00010000u for version 1.0. */

  FixedVersion<>fontRevision;		/* Set by font manufacturer. */

  ULONG		checkSumAdjustment;	/* To compute: set it to 0, sum the

					 * entire font as ULONG, then store

					 * 0xB1B0AFBAu - sum. */

  ULONG		magicNumber;		/* Set to 0x5F0F3CF5u. */

  USHORT	flags;			/* Bit 0: Baseline for font at y=0;

					 * Bit 1: Left sidebearing point at x=0;

					 * Bit 2: Instructions may depend on point size;

					 * Bit 3: Force ppem to integer values for all

					 *   internal scaler math; may use fractional

					 *   ppem sizes if this bit is clear;

					 * Bit 4: Instructions may alter advance width

					 *   (the advance widths might not scale linearly);

					 * Bits 5-10: These should be set according to

					 *   Apple's specification. However, they are not

					 *   implemented in OpenType.

					 * Bit 5: This bit should be set in fonts that are

					 *   intended to e laid out vertically, and in

					 *   which the glyphs have been drawn such that an

					 *   x-coordinate of 0 corresponds to the desired

					 *   vertical baseline.

					 * Bit 6: This bit must be set to zero.

					 * Bit 7: This bit should be set if the font

					 *   requires layout for correct linguistic

					 *   rendering (e.g. Arabic fonts).

					 * Bit 8: This bit should be set for a GX font

					 *   which has one or more metamorphosis effects

					 *   designated as happening by default.

					 * Bit 9: This bit should be set if the font

					 *   contains any strong right-to-left glyphs.

					 * Bit 10: This bit should be set if the font

					 *   contains Indic-style rearrangement effects.

					 * Bit 11: Font data is 'lossless,' as a result

					 *   of having been compressed and decompressed

					 *   with the Agfa MicroType Express engine.

					 * Bit 12: Font converted (produce compatible metrics)

					 * Bit 13: Font optimized for ClearType™.

					 *   Note, fonts that rely on embedded bitmaps (EBDT)

					 *   for rendering should not be considered optimized

					 *   for ClearType, and therefore should keep this bit

					 *   cleared.

					 * Bit 14: Last Resort font. If set, indicates that

					 * the glyphs encoded in the cmap subtables are simply

					 * generic symbolic representations of code point

					 * ranges and don’t truly represent support for those

					 * code points. If unset, indicates that the glyphs

					 * encoded in the cmap subtables represent proper

					 * support for those code points.

					 * Bit 15: Reserved, set to 0. */

  USHORT	unitsPerEm;		/* Valid range is from 16 to 16384. This value

					 * should be a power of 2 for fonts that have

					 * TrueType outlines. */

  LONGDATETIME	created;		/* Number of seconds since 12:00 midnight,

					   January 1, 1904. 64-bit integer */

  LONGDATETIME	modified;		/* Number of seconds since 12:00 midnight,

					   January 1, 1904. 64-bit integer */

  SHORT		xMin;			/* For all glyph bounding boxes. */

  SHORT		yMin;			/* For all glyph bounding boxes. */

  SHORT		xMax;			/* For all glyph bounding boxes. */

  SHORT		yMax;			/* For all glyph bounding boxes. */

  USHORT	macStyle;		/* Bit 0: Bold (if set to 1);

					 * Bit 1: Italic (if set to 1)

					 * Bit 2: Underline (if set to 1)

					 * Bit 3: Outline (if set to 1)

					 * Bit 4: Shadow (if set to 1)

					 * Bit 5: Condensed (if set to 1)

					 * Bit 6: Extended (if set to 1)

					 * Bits 7-15: Reserved (set to 0). */

  USHORT	lowestRecPPEM;		/* Smallest readable size in pixels. */

  SHORT		fontDirectionHint;	/* Deprecated (Set to 2).

					 * 0: Fully mixed directional glyphs;

					 * 1: Only strongly left to right;

					 * 2: Like 1 but also contains neutrals;

					 * -1: Only strongly right to left;

					 * -2: Like -1 but also contains neutrals. */

  public:

  SHORT		indexToLocFormat;	/* 0 for short offsets, 1 for long. */

  SHORT		glyphDataFormat;	/* 0 for current format. */

  DEFINE_SIZE_STATIC (54);

};

} /* namespace OT */

#endif /* HB_OT_HEAD_TABLE_HH */