Font addons

These functions are declared in the following header file. Link with allegro_font.

     #include <allegro5/allegro_font.h>

# General font routines

## ALLEGRO_FONT

    typedef struct ALLEGRO_FONT ALLEGRO_FONT;

Source Code

A handle identifying any kind of font. Usually you will create it with al_load_font which supports loading all kinds of TrueType fonts supported by the FreeType library. If you instead pass the filename of a bitmap file, it will be loaded with al_load_bitmap and a font in Allegro’s bitmap font format will be created from it with al_grab_font_from_bitmap.

Examples:

- ex_disable_screensaver.c
- ex_font_justify.cpp
- ex_timedwait.c

## ALLEGRO_GLYPH

    typedef struct ALLEGRO_GLYPH ALLEGRO_GLYPH;

Source Code

A structure containing the properties of a character in a font.

    typedef struct ALLEGRO_GLYPH {
       ALLEGRO_BITMAP *bitmap;   // the bitmap the character is on
       int x;                    // the x position of the glyph on bitmap
       int y;                    // the y position of the glyph on bitmap
       int w;                    // the width of the glyph in pixels
       int h;                    // the height of the glyph in pixels
       int kerning;              // pixels of kerning (see below)
       int offset_x;             // x offset to draw the glyph at
       int offset_y;             // y offset to draw the glyph at
       int advance;              // number of pixels to advance after this character
    } ALLEGRO_GLYPH;

bitmap may be a sub-bitmap in the case of color fonts. Bitmap can also be NULL in which case nothing should be drawn (sometimes true for whitespace characters in TTF fonts).

kerning should be added to the x position you draw to if you want your text kerned and depends on which codepoints al_get_glyph was called with.

Glyphs are tightly packed onto the bitmap, so you need to add offset_x and offset_y to your draw position for the text to look right.

advance is the number of pixels to add to your x position to advance to the next character in a string and includes kerning.

Since: 5.2.1

> Unstable API: This API is new and subject to refinement.

See also: al_get_glyph

Examples:

- ex_ttf.c

## al_init_font_addon

    bool al_init_font_addon(void)

Source Code

Initialise the font addon.

Note that if you intend to load bitmap fonts, you will need to initialise allegro_image separately (unless you are using another library to load images).

Similarly, if you wish to load truetype-fonts, do not forget to also call al_init_ttf_addon.

Returns true on success, false on failure. On the 5.0 branch, this function has no return value. You may wish to avoid checking the return value if your code needs to be compatible with Allegro 5.0. Currently, the function will never return false.

See also: al_init_image_addon, al_init_ttf_addon, al_shutdown_font_addon

Examples:

- ex_disable_screensaver.c
- ex_font_justify.cpp
- ex_timedwait.c

## al_is_font_addon_initialized

    bool al_is_font_addon_initialized(void)

Source Code

Returns true if the font addon is initialized, otherwise returns false.

Since: 5.2.6

See also: al_init_font_addon, al_shutdown_font_addon

## al_shutdown_font_addon

    void al_shutdown_font_addon(void)

Source Code

Shut down the font addon. This is done automatically at program exit, but can be called any time the user wishes as well.

See also: al_init_font_addon

## al_load_font

    ALLEGRO_FONT *al_load_font(char const *filename, int size, int flags)

Source Code

Loads a font from disk. This will use al_load_bitmap_font_flags if you pass the name of a known bitmap format, or else al_load_ttf_font.

The flags parameter is passed through to either of those functions. Bitmap and TTF fonts are also affected by the current bitmap flags at the time the font is loaded.

See also: al_destroy_font, al_init_font_addon, al_register_font_loader, al_load_bitmap_font_flags, al_load_ttf_font

Examples:

- ex_font_justify.cpp
- ex_membmp.c
- ex_window_title.c

## al_destroy_font

    void al_destroy_font(ALLEGRO_FONT *f)

Source Code

Frees the memory being used by a font structure. Does nothing if passed NULL.

See also: al_load_font

Examples:

- ex_disable_screensaver.c
- ex_font_justify.cpp
- ex_cpu.c

## al_register_font_loader

    bool al_register_font_loader(char const *extension,
       ALLEGRO_FONT *(*load_font)(char const *filename, int size, int flags))

Source Code

Informs Allegro of a new font file type, telling it how to load files of this format.

The `extension` should include the leading dot (‘.’) character. It will be matched case-insensitively.

The `load_font` argument may be NULL to unregister an entry.

Returns true on success, false on error. Returns false if unregistering an entry that doesn’t exist.

See also: al_init_font_addon

## al_get_font_line_height

    int al_get_font_line_height(const ALLEGRO_FONT *f)

Source Code

Returns the usual height of a line of text in the specified font. For bitmap fonts this is simply the height of all glyph bitmaps. For truetype fonts it is whatever the font file specifies. In particular, some special glyphs may be higher than the height returned here.

If the X is the position you specify to draw text, the meaning of ascent and descent and the line height is like in the figure below.

    X------------------------
        /\         |        |
       /  \        |        |
      /____\       ascent   |
     /      \      |        |
    /        \     |        height
    ----------------        |
                   |        |
                   descent  |
                   |        |
    -------------------------

See also: al_get_text_width, al_get_text_dimensions

Examples:

- ex_font_justify.cpp
- ex_membmp.c
- ex_mouse_warp.c

## al_get_font_ascent

    int al_get_font_ascent(const ALLEGRO_FONT *f)

Source Code

Returns the ascent of the specified font.

See also: al_get_font_descent, al_get_font_line_height

Examples:

- ex_ttf.c

## al_get_font_descent

    int al_get_font_descent(const ALLEGRO_FONT *f)

Source Code

Returns the descent of the specified font.

See also: al_get_font_ascent, al_get_font_line_height

Examples:

- ex_ttf.c

## al_get_text_width

    int al_get_text_width(const ALLEGRO_FONT *f, const char *str)

Source Code

Calculates the length of a string in a particular font, in pixels.

See also: al_get_ustr_width, al_get_font_line_height, al_get_text_dimensions

Examples:

- ex_display_options.c
- ex_record_name.c
- ex_color_gradient.c

## al_get_ustr_width

    int al_get_ustr_width(const ALLEGRO_FONT *f, ALLEGRO_USTR const *ustr)

Source Code

Like al_get_text_width but expects an ALLEGRO_USTR.

See also: al_get_text_width, al_get_ustr_dimensions

Examples:

- nihgui.cpp

## al_draw_text

    void al_draw_text(const ALLEGRO_FONT *font,
       ALLEGRO_COLOR color, float x, float y, int flags,
       char const *text)

Source Code

Writes the NUL-terminated string `text` onto the target bitmap at position `x`, `y`, using the specified `font`.

The `flags` parameter can be 0 or one of the following flags:

- ALLEGRO_ALIGN_LEFT - Draw the text left-aligned (same as 0).
- ALLEGRO_ALIGN_CENTRE - Draw the text centered around the given position.
- ALLEGRO_ALIGN_RIGHT - Draw the text right-aligned to the given position.

It can also be combined with this flag:

- ALLEGRO_ALIGN_INTEGER - Always draw text aligned to an integer pixel position. This was formerly the default behaviour. Since: 5.0.8, 5.1.4

This function does not support newline characters (`\n`), but you can use al_draw_multiline_text for multi line text output.

See also: al_draw_ustr, al_draw_textf, al_draw_justified_text, al_draw_multiline_text.

Examples:

- ex_disable_screensaver.c
- ex_timedwait.c
- ex_display_events.c

## al_draw_ustr

    void al_draw_ustr(const ALLEGRO_FONT *font,
       ALLEGRO_COLOR color, float x, float y, int flags,
       const ALLEGRO_USTR *ustr)

Source Code

Like al_draw_text, except the text is passed as an ALLEGRO_USTR instead of a NUL-terminated char array.

See also: al_draw_text, al_draw_justified_ustr, al_draw_multiline_ustr

Examples:

- ex_font_multiline.cpp
- nihgui.cpp
- ex_blend.c

## al_draw_justified_text

    void al_draw_justified_text(const ALLEGRO_FONT *font,
       ALLEGRO_COLOR color, float x1, float x2,
       float y, float diff, int flags, const char *text)

Source Code

Like al_draw_text, but justifies the string to the region x1-x2.

The `diff` parameter is the maximum amount of horizontal space to allow between words. If justisfying the text would exceed `diff` pixels, or the string contains less than two words, then the string will be drawn left aligned.

The `flags` parameter can be 0 or one of the following flags:

- ALLEGRO_ALIGN_INTEGER - Draw text aligned to integer pixel positions. Since: 5.0.8, 5.1.5

See also: al_draw_justified_textf, al_draw_justified_ustr

Examples:

- ex_font_justify.cpp

## al_draw_justified_ustr

    void al_draw_justified_ustr(const ALLEGRO_FONT *font,
       ALLEGRO_COLOR color, float x1, float x2,
       float y, float diff, int flags, const ALLEGRO_USTR *ustr)

Source Code

Like al_draw_justified_text, except the text is passed as an ALLEGRO_USTR instead of a NUL-terminated char array.

See also: al_draw_justified_text, al_draw_justified_textf.

## al_draw_textf

    void al_draw_textf(const ALLEGRO_FONT *font, ALLEGRO_COLOR color,
       float x, float y, int flags,
       const char *format, ...)

Source Code

Formatted text output, using a printf() style format string. All parameters have the same meaning as with al_draw_text otherwise.

See also: al_draw_text, al_draw_ustr

Examples:

- ex_disable_screensaver.c
- ex_timedwait.c
- ex_display_events.c

## al_draw_justified_textf

    void al_draw_justified_textf(const ALLEGRO_FONT *f,
       ALLEGRO_COLOR color, float x1, float x2, float y,
       float diff, int flags, const char *format, ...)

Source Code

Formatted text output, using a printf() style format string. All parameters have the same meaning as with al_draw_justified_text otherwise.

See also: al_draw_justified_text, al_draw_justified_ustr.

## al_get_text_dimensions

    void al_get_text_dimensions(const ALLEGRO_FONT *f,
       char const *text,
       int *bbx, int *bby, int *bbw, int *bbh)

Source Code

Sometimes, the al_get_text_width and al_get_font_line_height functions are not enough for exact text placement, so this function returns some additional information.

Returned variables (all in pixels):

- x, y - Offset to upper left corner of bounding box.
- w, h - Dimensions of bounding box.

Note that glyphs may go to the left and upwards of the X, in which case x and y will have negative values.

See also: al_get_text_width, al_get_font_line_height, al_get_ustr_dimensions

Examples:

- ex_ttf.c
- ex_logo.c

## al_get_ustr_dimensions

    void al_get_ustr_dimensions(const ALLEGRO_FONT *f,
       ALLEGRO_USTR const *ustr,
       int *bbx, int *bby, int *bbw, int *bbh)

Source Code

Like al_get_text_dimensions, except the text is passed as an ALLEGRO_USTR instead of a NUL-terminated char array.

See also: al_get_text_dimensions

## al_get_allegro_font_version

    uint32_t al_get_allegro_font_version(void)

Source Code

Returns the (compiled) version of the addon, in the same format as al_get_allegro_version.

## al_get_font_ranges

    int al_get_font_ranges(ALLEGRO_FONT *f, int ranges_count, int *ranges)

Source Code

Gets information about all glyphs contained in a font, as a list of ranges. Ranges have the same format as with al_grab_font_from_bitmap.

`ranges_count` is the maximum number of ranges that will be returned.

`ranges` should be an array with room for `ranges_count` * 2 elements. The even integers are the first unicode point in a range, the odd integers the last unicode point in a range.

Returns the number of ranges contained in the font (even if it is bigger than `ranges_count`).

Since: 5.1.4

See also: al_grab_font_from_bitmap

Examples:

- ex_ttf.c

## al_set_fallback_font

    void al_set_fallback_font(ALLEGRO_FONT *font, ALLEGRO_FONT *fallback)

Source Code

Sets a font which is used instead if a character is not present. Can be chained, but make sure there is no loop as that would crash the application! Pass NULL to remove a fallback font again.

Since: 5.1.12

See also: al_get_fallback_font, al_draw_glyph, al_draw_text

Examples:

- ex_ttf.c

## al_get_fallback_font

    ALLEGRO_FONT *al_get_fallback_font(ALLEGRO_FONT *font)

Source Code

Retrieves the fallback font for this font or NULL.

Since: 5.1.12

See also: al_set_fallback_font

# Per glyph text handling

For some applications Allegro’s text drawing functions may not be sufficient. For example, you would like to give a different color to every letter in a word, or use different a font for a drop cap.

That is why Allegro supports drawing and getting the dimensions of the individual glyphs of a font. A glyph is a particular visual representation of a letter, character or symbol in a specific font.

And it’s also possible to get the kerning to use between two glyphs. These per glyph functions have less overhead than Allegro’s per string text drawing and dimensioning functions. So, with these functions you can write your own efficient and precise custom text drawing functions.

## al_draw_glyph

    void al_draw_glyph(const ALLEGRO_FONT *f, ALLEGRO_COLOR color, float x, float y,
       int codepoint)

Source Code

Draws the glyph that corresponds with `codepoint` in the given `color` using the given `font`. If `font` does not have such a glyph, nothing will be drawn.

To draw a string as left to right horizontal text you will need to use al_get_glyph_advance to determine the position of each glyph. For drawing strings in other directions, such as top to down, use al_get_glyph_dimensions to determine the size and position of each glyph.

If you have to draw many glyphs at the same time, use al_hold_bitmap_drawing with true as the parameter, before drawing the glyphs, and then call al_hold_bitmap_drawing again with false as a parameter when done drawing the glyphs to further enhance performance.

Since: 5.1.12

See also: al_get_glyph_width, al_get_glyph_dimensions, al_get_glyph_advance.

Examples:

- ex_font.c
- ex_ttf.c

## al_get_glyph_width

    int al_get_glyph_width(const ALLEGRO_FONT *f, int codepoint)

Source Code

This function returns the width in pixels of the glyph that corresponds with `codepoint` in the font `font`. Returns zero if the font does not have such a glyph.

Since: 5.1.12

See also: al_draw_glyph, al_get_glyph_dimensions, al_get_glyph_advance.

## al_get_glyph_dimensions

    bool al_get_glyph_dimensions(const ALLEGRO_FONT *f,
       int codepoint, int *bbx, int *bby, int *bbw, int *bbh)

Source Code

Sometimes, the al_get_glyph_width or al_get_glyph_advance functions are not enough for exact glyph placement, so this function returns some additional information, particularly if you want to draw the font vertically.

The function itself returns true if the character was present in `font` and false if the character was not present in `font`.

Returned variables (all in pixel):

- bbx, bby - Offset to upper left corner of bounding box.
- bbw, bbh - Dimensions of bounding box.

These values are the same as al_get_text_dimensions would return for a string of a single character equal to the glyph passed to this function. Note that glyphs may go to the left and upwards of the X, in which case x and y will have negative values.

If you want to draw a string verticallly, for Japanese or as a game effect, then you should leave bby + bbh space between the glyphs in the y direction for a regular placement.

If you want to draw a string horizontally in an extra compact way,
then you should leave bbx + bbw space between the glyphs in the x direction for a compact placement.

In the figure below is an example of what bbx and bby may be like for a `2` glyph, and a `g` glyph of the same font compared to the result of al_get_glyph_width().

       al_get_glyph_width()     al_get_glyph_width()
              __|___                   __|__
             /      \                 /     \
         bbx    bbw                 bbx   bbw
        <-->+<------>+           <-->+<----->+   X baseline
        ^   |        |           ^   |       |
    bby |   |        |       bby |   |       |
        v   |        |           |   |       |
        +---+--------+           |   |       |
        ^   | *****  |           |   |       |
        |   |*    ** |           v   |       |
    bbh |   |    **  |       bbh +---+-------+
        |   |  **    |           ^   | ***** |
        v   |********|           |   |*     *|
        +---+--------+           |   | ***** |
                                 |   |      *|
                                 |   | *    *|
                                 v   |  **** |
                                 +---+-------+

Since: 5.1.12

See also: al_draw_glyph, al_get_glyph_width, al_get_glyph_advance.

Examples:

- ex_ttf.c

## al_get_glyph_advance

    int al_get_glyph_advance(const ALLEGRO_FONT *f, int codepoint1, int codepoint2)

Source Code

This function returns by how much the x position should be advanced for left to right text drawing when the glyph that corresponds to codepoint1 has been drawn, and the glyph that corresponds to codepoint2 will be the next to be drawn. This takes into consideration the horizontal advance width of the glyph that corresponds with codepoint1 as well as the kerning between the glyphs of codepoint1 and codepoint2.

Kerning is the process of adjusting the spacing between glyphs in a font, to obtain a more visually pleasing result. Kerning adjusts the space between two individual glyphs with an offset determined by the author of the font.

If you pass ALLEGRO_NO_KERNING as codepoint1 then al_get_glyph_advance will return 0. this can be useful when drawing the first character of a string in a loop.

Pass ALLEGRO_NO_KERNING as codepoint2 to get the horizontal advance width of the glyph that corresponds to codepoint1 without taking any kerning into consideration. This can be used, for example, when drawing the last character of a string in a loop.

This function will return zero if the glyph of codepoint1 is not present in the `font`. If the glyph of codepoint2 is not present in the font, the horizontal advance width of the glyph that corresponds to codepoint1 without taking any kerning into consideration is returned.

When drawing a string one glyph at the time from the left to the right with kerning, the x position of the glyph should be incremented by the result of al_get_glyph_advance applied to the previous glyph drawn and the next glyph to draw.

Note that the return value of this function is a recommended advance for optimal readability for left to right text determined by the author of the font. However, if you like, you may want to draw the glyphs of the font narrower or wider to each other than what al_get_glyph_advance returns for style or effect.

In the figure below is an example of what the result of al_get_glyph_advance may be like for two glypphs `A` and `l` of the same font that has kerning for the “Al” pair, without and with the ALLEGRO_NO_KERNING flag.

    al_get_glyph_advance(font, 'A', 'l')
         ___|___
        /       \
        -------------
            /\   -|
           /  \   |
          /____\  |
         /      \ |
        /        \ \_
        -------------

    al_get_glyph_advance(font, 'A', ALLEGRO_NO_KERNING)
         ____|____
        /         \
        ---------------
            /\     -|
           /  \     |
          /____\    |
         /      \   |
        /        \   \_
        ---------------

Since: 5.1.12

See also: al_draw_glyph, al_get_glyph_width, al_get_glyph_dimensions.

Examples:

- ex_font.c
- ex_ttf.c

# Multiline text drawing

## al_draw_multiline_text

    void al_draw_multiline_text(const ALLEGRO_FONT *font,
         ALLEGRO_COLOR color, float x, float y, float max_width, float line_height,
         int flags, const char *text)

Source Code

Like al_draw_text, but this function supports drawing multiple lines of text. It will break `text` in lines based on its contents and the `max_width` parameter. The lines are then layed out vertically depending on the `line_height` parameter and drawn each as if al_draw_text was called on them.

A newline `\n` in the `text` will cause a “hard” line break after its occurrence in the string. The text after a hard break is placed on a new line. Carriage return `\r` is not supported, will not cause a line break, and will likely be drawn as a square or a space depending on the font.

The `max_width` parameter controls the maximum desired width of the lines. This function will try to introduce a “soft” line break after the longest possible series of words that will fit in `max_length` when drawn with the given `font`. A “soft” line break can occur either on a space or tab (`\t`) character.

However, it is possible that `max_width` is too small, or the words in `text` are too long to fit `max_width` when drawn with `font`. In that case, the word that is too wide will simply be drawn completely on a line by itself. If you don’t want the text that overflows `max_width` to be visible, then use al_set_clipping_rectangle to clip it off and hide it.

The lines `text` was split into will each be drawn using the `font`, `x`, `color` and `flags` parameters, vertically starting at `y` and with a distance of `line_height` between them. If `line_height` is zero (`0`), the value returned by calling al_get_font_line_height on `font` will be used as a default instead.

The `flags` ALLEGRO_ALIGN_LEFT, ALLEGRO_ALIGN_CENTRE, ALLEGRO_ALIGN_RIGHT and ALLEGRO_ALIGN_INTEGER will be honoured by this function.

If you want to calculate the size of what this function will draw without actually drawing it, or if you need a complex and/or custom layout, you can use al_do_multiline_text.

Since: 5.1.9

See also: al_do_multiline_text, al_draw_multiline_ustr, al_draw_multiline_textf

Examples:

- ex_font_multiline.cpp
- ex_resize2.c

## al_draw_multiline_ustr

    void al_draw_multiline_ustr(const ALLEGRO_FONT *font,
         ALLEGRO_COLOR color, float x, float y, float max_width, float line_height,
         int flags, const ALLEGRO_USTR *ustr)

Source Code

Like al_draw_multiline_text, except the text is passed as an ALLEGRO_USTR instead of a NUL-terminated char array.

Since: 5.1.9

See also: al_draw_multiline_text, al_draw_multiline_textf, al_do_multiline_text

## al_draw_multiline_textf

    void al_draw_multiline_textf(const ALLEGRO_FONT *font,
         ALLEGRO_COLOR color, float x, float y, float max_width, float line_height,
         int flags, const char *format, ...)

Source Code

Formatted text output, using a printf() style format string. All parameters have the same meaning as with al_draw_multiline_text otherwise.

Since: 5.1.9

See also: al_draw_multiline_text, al_draw_multiline_ustr, al_do_multiline_text

Examples:

- ex_resize2.c

## al_do_multiline_text

    void al_do_multiline_text(const ALLEGRO_FONT *font,
       float max_width, const char *text,
       bool (*cb)(int line_num, const char *line, int size, void *extra),
       void *extra)

Source Code

This function processes the `text` and splits it into lines as al_draw_multiline_text would, and then calls the callback `cb` once for every line. This is useful for custom drawing of multiline text, or for calculating the size of multiline text ahead of time. See the documentation on al_draw_multiline_text for an explanation of the splitting algorithm.

For every line that this function splits `text` into the callback `cb` will be called once with the following parameters:

- `line_num` - the number of the line starting from zero and counting up
- `line` - a pointer to the beginning character of the line (see below)
- `size` - the size of the line (0 for empty lines)
- `extra` - the same pointer that was passed to al_do_multiline_text

Note that `line` is not guaranteed to be a NUL-terminated string, but will merely point to a character within `text` or to an empty string in case of an empty line. If you need a NUL-terminated string, you will have to copy `line` to a buffer and NUL-terminate it yourself. You will also have to make your own copy if you need the contents of `line` after `cb` has returned, as `line` is not guaranteed to be valid after that.

If the callback `cb` returns false, al_do_multiline_text will stop immediately, otherwise it will continue on to the next line.

Since: 5.1.9

See also: al_draw_multiline_text

Examples:

- ex_font_multiline.cpp

## al_do_multiline_ustr

    void al_do_multiline_ustr(const ALLEGRO_FONT *font, float max_width,
       const ALLEGRO_USTR *ustr,
       bool (*cb)(int line_num, const ALLEGRO_USTR * line, void *extra),
       void *extra)

Source Code

Like al_do_multiline_text, but using ALLEGRO_USTR instead of a NUL-terminated char array for text.

Since: 5.1.9

See also: al_draw_multiline_ustr

# Bitmap fonts

## al_grab_font_from_bitmap

    ALLEGRO_FONT *al_grab_font_from_bitmap(ALLEGRO_BITMAP *bmp,
       int ranges_n, const int ranges[])

Source Code

Creates a new font from an Allegro bitmap. You can delete the bitmap after the function returns as the font will contain a copy for itself.

Parameters:

- bmp: The bitmap with the glyphs drawn onto it
- n: Number of unicode ranges in the bitmap.
- ranges: ‘n’ pairs of first and last unicode point to map glyphs to for each range.

The bitmap format is as in the following example, which contains three glyphs for 1, 2 and 3.

    .............
    . 1 .222.333.
    . 1 .  2.  3.
    . 1 .222.333.
    . 1 .2  .  3.
    . 1 .222.333.
    .............

In the above illustration, the dot is for pixels having the background color. It is determined by the color of the top left pixel in the bitmap. There should be a border of at least 1 pixel with this color to the bitmap edge and between all glyphs.

Each glyph is inside a rectangle of pixels not containing the background color. The height of all glyph rectangles should be the same, but the width can vary.

The placement of the rectangles does not matter, except that glyphs are scanned from left to right and top to bottom to match them to the specified unicode codepoints.

The glyphs will simply be drawn using al_draw_bitmap, so usually you will want the rectangles filled with full transparency and the glyphs drawn in opaque white.

Examples:

    int ranges[] = {32, 126};
    al_grab_font_from_bitmap(bitmap, 1, ranges)

    int ranges[] = {
        0x0020, 0x007F,  /* ASCII */
        0x00A1, 0x00FF,  /* Latin 1 */
        0x0100, 0x017F,  /* Extended-A */
        0x20AC, 0x20AC}; /* Euro */
    al_grab_font_from_bitmap(bitmap, 4, ranges)

The first example will grab glyphs for the 95 standard printable ASCII characters, beginning with the space character (32) and ending with the tilde character (126). The second example will map the first 96 glyphs found in the bitmap to ASCII range, the next 95 glyphs to Latin 1, the next 128 glyphs to Extended-A, and the last glyph to the Euro character. (This is just the characters found in the Allegro 4 font.)

See also: al_load_bitmap, al_grab_font_from_bitmap

Examples:

- ex_font.c
- ex_ttf.c

## al_load_bitmap_font

    ALLEGRO_FONT *al_load_bitmap_font(const char *fname)

Source Code

Load a bitmap font from a file. This is done by first calling al_load_bitmap_flags and then al_grab_font_from_bitmap.

If you wanted to load an old A4 font, for example, it would be better to load the bitmap yourself in order to call al_convert_mask_to_alpha on it before passing it to al_grab_font_from_bitmap.

See also: al_load_bitmap_font_flags, al_load_font, al_load_bitmap_flags

Examples:

- ex_bitmap_flip.c
- ex_mouse_cursor.c
- ex_record_name.c

## al_load_bitmap_font_flags

    ALLEGRO_FONT *al_load_bitmap_font_flags(const char *fname, int flags)

Source Code

Like al_load_bitmap_font but additionally takes a flags parameter which is a bitfield containing a combination of the following:

ALLEGRO_NO_PREMULTIPLIED_ALPHA
  The same meaning as for al_load_bitmap_flags.

See also: al_load_bitmap_font, al_load_bitmap_flags

## al_create_builtin_font

    ALLEGRO_FONT *al_create_builtin_font(void)

Source Code

Creates a monochrome bitmap font (8x8 pixels per character).

This font is primarily intended to be used for displaying information in environments or during early runtime states where no external font data is available or loaded (e.g. for debugging).

The builtin font contains the following unicode character ranges:

    0x0020 to 0x007F (ASCII)
    0x00A1 to 0x00FF (Latin 1)
    0x0100 to 0x017F (Extended A)
    0x20AC to 0x20AC (euro currency symbol)

Returns NULL on an error.

The font memory must be freed the same way as for any other font, using al_destroy_font.

Since: 5.0.8, 5.1.3

See also: al_load_bitmap_font, al_destroy_font

Examples:

- ex_disable_screensaver.c
- ex_timedwait.c
- ex_display_events.c

# TTF fonts

These functions are declared in the following header file. Link with allegro_ttf.

     #include <allegro5/allegro_ttf.h>

## al_init_ttf_addon

    bool al_init_ttf_addon(void)

Source Code

Call this after al_init_font_addon to make al_load_font recognize “.ttf” and other formats supported by al_load_ttf_font.

Returns true on success, false on failure.

Examples:

- ex_font_justify.cpp
- ex_font_multiline.cpp
- ex_color.cpp

## al_is_ttf_addon_initialized

    bool al_is_ttf_addon_initialized(void)

Source Code

Returns true if the TTF addon is initialized, otherwise returns false.

Since: 5.2.6

See also: al_init_ttf_addon, al_shutdown_ttf_addon

## al_shutdown_ttf_addon

    void al_shutdown_ttf_addon(void)

Source Code

Unloads the ttf addon again. You normally don’t need to call this.

## al_load_ttf_font

    ALLEGRO_FONT *al_load_ttf_font(char const *filename, int size, int flags)

Source Code

Loads a TrueType font from a file using the FreeType library. Quoting from the FreeType FAQ this means support for many different font formats:

TrueType, OpenType, Type1, CID, CFF, Windows FON/FNT, X11 PCF, and others

The `size` parameter determines the size the font will be rendered at, specified in pixels. The standard font size is measured in units per EM, if you instead want to specify the size as the total height of glyphs in pixels, pass it as a negative value.

> Note: If you want to display text at multiple sizes, load the font multiple times with different size parameters.

The following flags are supported:

- ALLEGRO_TTF_NO_KERNING - Do not use any kerning even if the font file supports it.

- ALLEGRO_TTF_MONOCHROME - Load as a monochrome font (which means no anti-aliasing of the font is done).

- ALLEGRO_TTF_NO_AUTOHINT - Disable the Auto Hinter which is enabled by default in newer versions of FreeType. Since: 5.0.6, 5.1.2

See also: al_init_ttf_addon, al_load_ttf_font_f

Examples:

- ex_bitmap_flip.c
- ex_synth.cpp
- ex_audio_chain.cpp

## al_load_ttf_font_f

    ALLEGRO_FONT *al_load_ttf_font_f(ALLEGRO_FILE *file,
        char const *filename, int size, int flags)

Source Code

Like al_load_ttf_font, but the font is read from the file handle. The filename is only used to find possible additional files next to a font file.

> Note: The file handle is owned by the returned ALLEGRO_FONT object and must not be freed by the caller, as FreeType expects to be able to read from it at a later time.

## al_load_ttf_font_stretch

    ALLEGRO_FONT *al_load_ttf_font_stretch(char const *filename, int w, int h,
       int flags)

Source Code

Like al_load_ttf_font, except it takes separate width and height parameters instead of a single size parameter.

If the height is a positive value, and the width zero or positive, then font will be stretched according to those parameters. The width must not be negative if the height is positive.

As with al_load_ttf_font, the height may be a negative value to specify the total height in pixels. Then the width must also be a negative value, or zero.

Returns `NULL` if the height is positive while width is negative, or if the height is negative while the width is positive.

Since: 5.0.6, 5.1.0

See also: al_load_ttf_font, al_load_ttf_font_stretch_f

## al_load_ttf_font_stretch_f

    ALLEGRO_FONT *al_load_ttf_font_stretch_f(ALLEGRO_FILE *file,
        char const *filename, int w, int h, int flags)

Source Code

Like al_load_ttf_font_stretch, but the font is read from the file handle. The filename is only used to find possible additional files next to a font file.

> Note: The file handle is owned by the returned ALLEGRO_FONT object and must not be freed by the caller, as FreeType expects to be able to read from it at a later time.

Since: 5.0.6, 5.1.0

See also: al_load_ttf_font_stretch

## al_get_allegro_ttf_version

    uint32_t al_get_allegro_ttf_version(void)

Source Code

Returns the (compiled) version of the addon, in the same format as al_get_allegro_version.

## al_get_glyph

    bool al_get_glyph(const ALLEGRO_FONT *f, int prev_codepoint, int codepoint, ALLEGRO_GLYPH *glyph)

Source Code

Gets all the information about a glyph, including the bitmap, needed to draw it yourself. prev_codepoint is the codepoint in the string before the one you want to draw and is used for kerning. codepoint is the character you want to get info about. You should clear the ‘glyph’ structure to 0 with memset before passing it to this function for future compatibility.

Since: 5.2.1

> Unstable API: This API is new and subject to refinement.

See also: ALLEGRO_GLYPH

Examples:

- ex_font.c
- ex_ttf.c

Allegro version 5.2.10 - Last updated: 2024-12-29 03:54:50 UTC