msapi_font.h

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#ifndef _MSAPI_FONT_H
#define	_MSAPI_FONT_H

#include "DataType.h"

#ifdef MSAPI_FONT_C
#define INTERFACE
#else
#define INTERFACE extern
#endif

// Tags to identify a valid font header
#define FONT_HEADER_TAG    0x466f4E74

// Font compression method
#define FONT_COMPRESSION_NONE               0x00
#define FONT_COMPRESSION_BOUND_RECTANGLE    0x01
#define FONT_COMPRESSION_RUN_LENGTH         0x02
//#define FONT_COMPRESSION_HUFFMAN            0x03

/// Font target bits per pixel  
typedef enum // for ATSC_TRUNK
{
    FONT_TARGET_BPP_NO_CHANGE,  ///< Target BPP is the same as source
    FONT_TARGET_BPP_I2_VARIANT  ///< Target BPP is converted from I2 to 3 I1. Used for blinking text that appears in closed caption.
} EN_FONT_TARGET_BPP;

/// Structure for a font table
typedef struct
{
    FONTHANDLE fHandle;         ///< Font handle
} FONT;

/// Font bin header
typedef struct {
    U32     u32Tag;                 ///< Default is 0x466f4E74
    U32     u32BPP;                 ///< Bits Per Pixel. I1: 0x01, I2: 0x02, I2 variant: 0x03 (for Saturn)
    U32     u32CharNum;             ///< Character count
    U32     u32Width;               ///< Width in pixels of a font
    U32     u32Height;              ///< Height in pixels of a font
    U32     u32Pitch;               ///< Font pitch in bytes
    U32     u32Compression;         ///< 0x00 for none compression, 0x01 for bounding rectangle
    // BBox (Bounding Box) describes the smallest rectangle that encloses the shape/outline of each glyph
    U32     u32BBoxOffset;          ///< Offset of BBox information
    U32     u32CodemapOffset;       ///< Offset of codemap block data. Each codemap block is a tuple of(start code, end code, start index)
    U32     u32CodemapBlockNum;     ///< Number of codemap block.
    U32     u32CharGlyphBytes;      ///< Size of one char glyph including possible paddings for alignment
    U32     u32FontGlyphOffset;     ///< Offset of glyph data
    U32     u32FontGlyphBytes;      ///< Length of all the glyph data, depending on u8Compression.
} FONT_BIN_HEADER;

INTERFACE bool msAPI_Font_ReadBinHeader(U16 u16FontBinID, FONT_BIN_HEADER *pFontBinHeader, U32 *pu32BinBaseAddr);
INTERFACE U8  msAPI_Font_GetLineBytes(const FONT_BIN_HEADER *pFontBinHeader);
INTERFACE U16 msAPI_Font_GetCharGlyphBytes(const FONT_BIN_HEADER *pFontBinHeader);
INTERFACE U32 msAPI_Font_GetFontGlyphBytes(const FONT_BIN_HEADER *pFontBinHeader);

#undef INTERFACE

#endif