Win32 Fonts and Rendering

## Win32 Fonts and Rendering Win32 Fonts and Rendering — Functions for shape engines to manipulate Win32 fonts |

## Synopsis

    #define     PANGO_RENDER_TYPE_WIN32
    PangoContext* pango_win32_get_context       (void);
    void        pango_win32_render              (HDC hdc,
                                                 PangoFont *font,
                                                 PangoGlyphString *glyphs,
                                                 gint x,
                                                 gint y);
    void        pango_win32_render_transformed  (HDC hdc,
                                                 const PangoMatrix *matrix,
                                                 PangoFont *font,
                                                 PangoGlyphString *glyphs,
                                                 int x,
                                                 int y);
    void        pango_win32_render_layout_line  (HDC hdc,
                                                 PangoLayoutLine *line,
                                                 int x,
                                                 int y);
    void        pango_win32_render_layout       (HDC hdc,
                                                 PangoLayout *layout,
                                                 int x,
                                                 int y);
    PangoGlyph  pango_win32_get_unknown_glyph   (PangoFont *font,
                                                 gunichar wc);
    gint        pango_win32_font_get_glyph_index
                                                (PangoFont *font,
                                                 gunichar wc);
    gboolean    pango_win32_font_select_font    (PangoFont *font,
                                                 HDC hdc);
    void        pango_win32_font_done_font      (PangoFont *font);
    double      pango_win32_font_get_metrics_factor
                                                (PangoFont *font);
    gboolean    pango_win32_get_debug_flag      (void);
    HDC         pango_win32_get_dc              (void);
                PangoWin32FontCache;
    PangoWin32FontCache* pango_win32_font_cache_new
                                                (void);
    void        pango_win32_font_cache_free     (PangoWin32FontCache *cache);
    HFONT       pango_win32_font_cache_load     (PangoWin32FontCache *cache,
                                                 const LOGFONT *logfont);
    void        pango_win32_font_cache_unload   (PangoWin32FontCache *cache,
                                                 HFONT hfont);
    PangoFontMap* pango_win32_font_map_for_display
                                                (void);
    void        pango_win32_shutdown_display    (void);
    PangoWin32FontCache* pango_win32_font_map_get_font_cache
                                                (PangoFontMap *font_map);
    LOGFONT*    pango_win32_font_logfont        (PangoFont *font);
    PangoFontDescription* pango_win32_font_description_from_logfont
                                                (const LOGFONT *lfp);

## Description

The macros and functions in this section are used to access fonts natively on Win32 systems and to render text in conjunction with Win32 APIs.

## Details

### PANGO_RENDER_TYPE_WIN32

    #define PANGO_RENDER_TYPE_WIN32 "PangoRenderWin32"

A string constant identifying the Win32 renderer. The associated quark (see `g_quark_from_string()`) is used to identify the renderer in `pango_find_map()`.

### pango_win32_get_context ()

    PangoContext* pango_win32_get_context       (void);

Retrieves a PangoContext appropriate for rendering with Windows fonts.

Returns : | the new PangoContext

### pango_win32_render ()

    void        pango_win32_render              (HDC hdc,
                                                 PangoFont *font,
                                                 PangoGlyphString *glyphs,
                                                 gint x,
                                                 gint y);

Render a PangoGlyphString onto a Windows DC

`hdc` : | the device context
`font` : | the font in which to draw the string
`glyphs` : | the glyph string to draw
`x` : | the x position of start of string (in pixels)
`y` : | the y position of baseline (in pixels)

### pango_win32_render_transformed ()

    void        pango_win32_render_transformed  (HDC hdc,
                                                 const PangoMatrix *matrix,
                                                 PangoFont *font,
                                                 PangoGlyphString *glyphs,
                                                 int x,
                                                 int y);

Renders a PangoGlyphString onto a windows DC, possibly transforming the layed-out coordinates through a transformation matrix. Note that the transformation matrix for `font` is not changed, so to produce correct rendering results, the `font` must have been loaded using a PangoContext with an identical transformation matrix to that passed in to this function.

`hdc` : | a windows device context
`matrix` : | a PangoMatrix, or `NULL` to use an identity transformation
`font` : | the font in which to draw the string
`glyphs` : | the glyph string to draw
`x` : | the x position of the start of the string (in Pango units in user space coordinates)
`y` : | the y position of the baseline (in Pango units in user space coordinates)

### pango_win32_render_layout_line ()

    void        pango_win32_render_layout_line  (HDC hdc,
                                                 PangoLayoutLine *line,
                                                 int x,
                                                 int y);

Render a PangoLayoutLine onto a device context. For underlining to work property the text alignment of the DC should have TA_BASELINE and TA_LEFT.

`hdc` : | DC to use for uncolored drawing
`line` : | a PangoLayoutLine
`x` : | the x position of start of string (in pixels)
`y` : | the y position of baseline (in pixels)

### pango_win32_render_layout ()

    void        pango_win32_render_layout       (HDC hdc,
                                                 PangoLayout *layout,
                                                 int x,
                                                 int y);

Render a PangoLayoutLine onto an X drawable

`hdc` : | HDC to use for uncolored drawing
`layout` : | a PangoLayout
`x` : | the X position of the left of the layout (in pixels)
`y` : | the Y position of the top of the layout (in pixels)

### pango_win32_get_unknown_glyph ()

    PangoGlyph  pango_win32_get_unknown_glyph   (PangoFont *font,
                                                 gunichar wc);

### Warning

`pango_win32_get_unknown_glyph` is deprecated and should not be used in newly-written code.

Returns the index of a glyph suitable for drawing `wc` as an unknown character.

Use `PANGO_GET_UNKNOWN_GLYPH()` instead.

`font` : | a PangoFont
`wc` : | the Unicode character for which a glyph is needed.
Returns : | a glyph index into `font`

### pango_win32_font_get_glyph_index ()

    gint        pango_win32_font_get_glyph_index
                                                (PangoFont *font,
                                                 gunichar wc);

Obtains the index of the glyph for `wc` in `font`, or 0, if not covered.

`font` : | a PangoFont.
`wc` : | a Unicode character.
Returns : | the glyph index for `wc`.

### pango_win32_font_select_font ()

    gboolean    pango_win32_font_select_font    (PangoFont *font,
                                                 HDC hdc);

Selects the font into the specified DC and changes the mapping mode and world transformation of the DC appropriately for the font. You may want to surround the use of this function with calls to SaveDC and RestoreDC. Call `pango_win32_font_done_font()` when you are done using the DC to release allocated resources.

See `pango_win32_font_get_metrics_factor()` for information about converting from the coordinate space used by this function into Pango units.

`font` : | a PangoFont from the Win32 backend
`hdc` : | a windows device context
Returns : | `TRUE` if the operation succeeded.

### pango_win32_font_done_font ()

    void        pango_win32_font_done_font      (PangoFont *font);

Releases any resources allocated by `pango_win32_font_done_font()`

`font` : | a PangoFont from the win32 backend

### pango_win32_font_get_metrics_factor ()

    double      pango_win32_font_get_metrics_factor
                                                (PangoFont *font);

Returns the scale factor from logical units in the coordinate space used by `pango_win32_font_select_font()` to Pango units in user space.

`font` : | a PangoFont from the win32 backend
Returns : | factor to multiply logical units by to get Pango units.

### pango_win32_get_debug_flag ()

    gboolean    pango_win32_get_debug_flag      (void);

Returns wether debugging is turned on.

Returns : | `TRUE` if debugging is turned on.

Since 1.2

### pango_win32_get_dc ()

    HDC         pango_win32_get_dc              (void);

Obtains a handle to the Windows device context that is used by Pango.

Returns : | A handle to the Windows device context that is used by Pango.

### PangoWin32FontCache

    typedef struct _PangoWin32FontCache PangoWin32FontCache;

A PangoWin32FontCache caches HFONTs by their LOGFONT descriptions.

### pango_win32_font_cache_new ()

    PangoWin32FontCache* pango_win32_font_cache_new
                                                (void);

Creates a font cache.

Returns : | The new font cache. This must be freed with `pango_win32_font_cache_free()`.

### pango_win32_font_cache_free ()

    void        pango_win32_font_cache_free     (PangoWin32FontCache *cache);

Frees a PangoWin32FontCache and all associated memory. All fonts loaded through this font cache will be freed along with the cache.

`cache` : | a PangoWin32FontCache

### pango_win32_font_cache_load ()

    HFONT       pango_win32_font_cache_load     (PangoWin32FontCache *cache,
                                                 const LOGFONT *logfont);

Creates a HFONT from a LOGFONT. The result may be newly loaded, or it may have been previously stored

`cache` : | a PangoWin32FontCache
`logfont` : | a pointer to a LOGFONT structure describing the font to load.
Returns : | The font structure, or `NULL` if the font could not be loaded. In order to free this structure, you must call `pango_win32_font_cache_unload()`.

### pango_win32_font_cache_unload ()

    void        pango_win32_font_cache_unload   (PangoWin32FontCache *cache,
                                                 HFONT hfont);

Frees a font structure previously loaded with `pango_win32_font_cache_load()`.

`cache` : | a PangoWin32FontCache
`hfont` : | the HFONT to unload

### pango_win32_font_map_for_display ()

    PangoFontMap* pango_win32_font_map_for_display
                                                (void);

Returns a PangoWin32FontMap. Font maps are cached and should not be freed. If the font map is no longer needed, it can be released with `pango_win32_shutdown_display()`.

Returns : | a PangoFontMap.

### pango_win32_shutdown_display ()

    void        pango_win32_shutdown_display    (void);

Free cached resources.

### pango_win32_font_map_get_font_cache ()

    PangoWin32FontCache* pango_win32_font_map_get_font_cache
                                                (PangoFontMap *font_map);

Obtains the font cache associated with the given font map.

`font_map` : | a PangoWin32FontMap.
Returns : | the PangoWin32FontCache of `font_map`.

### pango_win32_font_logfont ()

    LOGFONT*    pango_win32_font_logfont        (PangoFont *font);

Determine the LOGFONT struct for the specified bfont.

`font` : | a PangoFont which must be from the Win32 backend
Returns : | A newly allocated LOGFONT struct. It must be freed with `g_free()`.

### pango_win32_font_description_from_logfont ()

    PangoFontDescription* pango_win32_font_description_from_logfont
                                                (const LOGFONT *lfp);

Creates a PangoFontDescription that matches the specified LOGFONT.

The face name, italicness and weight fields in the LOGFONT are used to set up the resulting PangoFontDescription. If the face name in the LOGFONT contains non-ASCII characters the font is temporarily loaded (using CreateFontIndirect) and an ASCII (usually English) name for it is looked up from the font name tables in the font data. If that doesn't work, the face name is converted from the system codepage to UTF-8 and that is used.

`lfp` : | a LOGFONT
Returns : | the newly allocated PangoFontDescription, which should be freed using `pango_font_desciption_free()`

Since 1.12