SDL::TTF - True Type Font functions (libfreetype)
TTF
The constants are exported by default. You can avoid this by doing:
use SDL::TTF ();
and access them directly:
SDL::TTF::TTF_HINTING_NORMAL;
Available constants for "hinting":
TTF_HINTING_NORMAL
TTF_HINTING_LIGHT
TTF_HINTING_MONO
TTF_HINTING_NONE
Available constants for "style":
TTF_STYLE_NORMAL
TTF_STYLE_BOLD
TTF_STYLE_ITALIC
TTF_STYLE_UNDERLINE
TTF_STYLE_STRIKETHROUGH
my $version = SDL::TTF::linked_version();
This gives you the SDL::Version object which SDL_ttf lib is used on the system. No prior initialization needs to be done before these function is called.
Example:
use SDL::TTF; use SDL::Version; my $version = SDL::TTF::linked_version(); printf("got version: %d.%d.%d\n", $version->major, $version->minor, $version->patch);
my $version = SDL::TTF::compile_time_version();
This gives you the SDL::Version object which SDL_ttf was present at compile time.
my $success = SDL::TTF::init();
Initialize the truetype font API. This must be called before using other functions in this library, except SDL::TTF::was_init and SDL::TTF::linked_version. SDL does not have to be initialized before this call.
Returns: 0 on success, -1 on any error.
0
-1
my $was_init = SDL::TTF::was_init();
Query the initilization status of the truetype font API. You may, of course, use this before SDL::TTF::init to avoid initializing twice in a row. Or use this to determine if you need to call SDL::TTF::quit.
SDL::TTF::quit();
Shutdown and cleanup the truetype font API. After calling this the SDL::TTF functions should not be used, excepting SDL::TTF::was_init. You may, of course, use SDL::TTF::init to use the functionality again
my $font = SDL::TTF::open_font($font_file, $point_size);
Load file for use as a font, at the given size. This is actually SDL::TTF::open_font_index(..., ..., $index = 0). This can load TTF and FON files.
SDL::TTF::open_font_index(..., ..., $index = 0)
Returns: a SDL::TTF::Font object. undef is returned on errors.
undef
use SDL::TTF; use SDL::TTF::Font; my $font = SDL::TTF::open_font('arial.ttf', 24);
my $font = SDL::TTF::open_font($font_file, $point_size, $face_index);
This is the same as SDL::TTF::open_font, except you can specify the face index of a font file containing multiple faces. This can load TTF and FON files.
my $font = SDL::TTF::open_font_RW($rwops_object, $free, $point_size);
This is the same as SDL::TTF::open_font, except you can pass an SDL::RWOps-object. If you pass true as $free, the SDL::RWOps-object will be freed by SDL_ttf library. Don't do this, perl will free this object for you.
$free
my $font = SDL::TTF::open_font_RW(SDL::RWOps->new_file($font_file, 'r'), 0, 24);
my $font = SDL::TTF::open_font_index_RW($rwops_object, $free, $point_size, $face_index);
This is the same as SDL::TTF::open_font_index, except you can pass an SDL::RWOps-object. If you pass true as $free, the SDL::RWOps-object will be freed by SDL_ttf library. Don't do this, perl will free this object for you.
SDL::TTF::byte_swapped_unicode( $bool );
This function tells SDL_ttf whether UNICODE (2 bytes per character) text is generally byteswapped. A UNICODE_BOM_NATIVE or UNICODE_BOM_SWAPPED character in a string will temporarily override this setting for the remainder of that string, however this setting will be restored for the next one. The default mode is non-swapped, native endianness of the CPU.
UNICODE_BOM_NATIVE
UNICODE_BOM_SWAPPED
SDL::TTF::get_font_style($font);
Returns: The style as a bitmask composed of the following masks:
TTF_STYLE_STRIKETHROUGH (since SDL_ttf 2.0.10)
my $style = SDL::TTF::get_font_style($font); print("normal\n") if $style == TTF_STYLE_NORMAL; print("bold\n") if $style & TTF_STYLE_BOLD; print("italic\n") if $style & TTF_STYLE_ITALIC; print("underline\n") if $style & TTF_STYLE_UNDERLINE; print("strikethrough\n") if $style & TTF_STYLE_STRIKETHROUGH;
SDL::TTF::set_font_style($font, $style);
Set the rendering style of the loaded font.
Note: TTF_STYLE_UNDERLINE may cause surfaces created by SDL::TTF::render_glyph_* functions to be extended vertically, downward only, to encompass the underline if the original glyph metrics didn't allow for the underline to be drawn below. This does not change the math used to place a glyph using glyph metrics. On the other hand TTF_STYLE_STRIKETHROUGH doesn't extend the glyph, since this would invalidate the metrics used to position the glyph when blitting, because they would likely be extended vertically upward. There is perhaps a workaround, but it would require programs to be smarter about glyph blitting math than they are currently designed for. Still, sometimes the underline or strikethrough may be outside of the generated surface, and thus not visible when blitted to the screen. In this case, you should probably turn off these styles and draw your own strikethroughs and underlines.
SDL::TTF::render_glyph_*
my $outline = SDL::TTF::get_font_outline($font);
Get the current outline width of the font, in pixels.
Note: at least SDL_ttf 2.0.10 needed
SDL::TTF::get_font_outline($font, $outline);
Set the outline pixel width of the loaded font. Use 0(zero) to turn off outlining.
my $hinting = SDL::TTF::get_font_hinting($font);
Get the current hinting setting of the loaded font.
Returns the hinting type matching one of the following defined values:
SDL::TTF::set_font_hinting($font, $hinting);
Set the hinting of the loaded font. You should experiment with this setting if you know which font you are using beforehand, especially when using smaller sized fonts. If the user is selecting a font, you may wish to let them select the hinting mode for that font as well.
SDL::TTF::set_font_hinting($font, TTF_HINTING_LIGHT);
my $kerning_enabled = SDL::TTF::get_font_kerning($font);
Get the current kerning setting of the loaded font.
Returns: 0(zero) if kerning is disabled. A non-zero value is returned when enabled. The default for a newly loaded font is enabled(1).
1
Note: This function returns wrong values: See http://bugzilla.libsdl.org/show_bug.cgi?id=973
SDL::TTF::set_font_kerning($font, $kerning_enabled);
Set whether to use kerning when rendering the loaded font. This has no effect on individual glyphs, but rather when rendering whole strings of characters, at least a word at a time. Perhaps the only time to disable this is when kerning is not working for a specific font, resulting in overlapping glyphs or abnormal spacing within words.
Pass 0 to disable kerning, 1 to enable.
my $font_height = SDL::TTF::font_height($font);
Get the maximum pixel height of all glyphs of the loaded font. You may use this height for rendering text as close together vertically as possible, though adding at least one pixel height to it will space it so they can't touch. Remember that SDL_ttf doesn't handle multiline printing, so you are responsible for line spacing, see the SDL::TTF::font_line_skip as well.
my $font_ascent = SDL::TTF::font_ascent($font);
Get the maximum pixel ascent of all glyphs of the loaded font. This can also be interpreted as the distance from the top of the font to the baseline. It could be used when drawing an individual glyph relative to a top point, by combining it with the glyph's maxy metric to resolve the top of the rectangle used when blitting the glyph on the screen.
maxy
my ($minx, $maxx, $miny, $maxy, $advance) = @{ SDL::TTF::glyph_metrics($font, "\0M") }; $rect->y( $top + SDL::TTF::font_ascent($font) - $maxy );
my $font_descent = SDL::TTF::font_descent($font);
Get the maximum pixel descent of all glyphs of the loaded font. This can also be interpreted as the distance from the baseline to the bottom of the font. It could be used when drawing an individual glyph relative to a bottom point, by combining it with the glyph's maxy metric to resolve the top of the rectangle used when blitting the glyph on the screen.
my ($minx, $maxx, $miny, $maxy, $advance) = @{ SDL::TTF::glyph_metrics($font, "\0M") }; $rect->y( $bottom - SDL::TTF::font_descent($font) - $maxy );
my $font_line_skip = SDL::TTF::font_line_skip($font);
Get the recommended pixel height of a rendered line of text of the loaded font. This is usually larger than the SDL::TTF::font_height of the font.
my $font_faces = SDL::TTF::font_faces($font);
Get the number of faces ("sub-fonts") available in the loaded font. This is a count of the number of specific fonts (based on size and style and other typographical features perhaps) contained in the font itself.
my $font_face_is_fixed_width = SDL::TTF::font_face_is_fixed_width($font);
Test if the current font face of the loaded font is a fixed width font. Fixed width fonts are monospace, meaning every character that exists in the font is the same width, thus you can assume that a rendered string's width is going to be the result of glyph_width * string_length.
glyph_width * string_length
Returns: >0 if font is a fixed width font. 0 if not a fixed width font.
>0
my $font_face_family_name = SDL::TTF::font_face_family_name($font);
Get the current font face family name from the loaded font. This information is not for every font available.
my $font = SDL::TTF::open_font('arialuni.ttf', 8); printf("%s\n", SDL::TTF::font_face_family_name($font)); # will print "Arial Unicode MS"
my $font_face_style_name = SDL::TTF::font_face_style_name($font);
Get the current font face style name from the loaded font. This information is not for every font available.
my $font = SDL::TTF::open_font('arialuni.ttf', 8); printf("%s\n", SDL::TTF::font_face_style_name($font)); # will print "Regular"
my $glyph_is_provided = SDL::TTF::glyph_is_provided($font, $unicode_char);
Get the status of the availability of the glyph from the loaded font.
Returns: the index of the glyph in font, or 0 for an undefined character code.
Note: You have to pass this unicode character either as UTF16/UCS-2 big endian without BOM, or with BOM as UTF16/UCS-2 big/little endian.
print("We have this char!\n") if SDL::TTF::glyph_is_provided($font, "\0M");
my @glyph_metrics = @{ SDL::TTF::glyph_metrics($font, $unicode_char) };
Get desired glyph metrics of the UNICODE char from the loaded font.
See also: The FreeType2 Documentation Tutorial
my ($minx, $maxx, $miny, $maxy, $advance) = @{ SDL::TTF::glyph_metrics($font, "\0M") };
my ($width, $height) = @{ SDL::TTF::size_text($font, $text) };
Calculate the resulting surface size of the LATIN1 encoded text rendered using $font. No actual rendering is done, however correct kerning is done to get the actual width. The height returned is the same as you can get using SDL::TTF::font_height.
$font
my ($width, $height) = @{ SDL::TTF::size_utf8($font, $text) };
Calculate the resulting surface size of the UTF8 encoded text rendered using $font. No actual rendering is done, however correct kerning is done to get the actual width. The height returned in h is the same as you can get using SDL::TTF::font_height.
Note that the first example uses the same text as in the LATIN1 example, that is because plain ASCII is UTF8 compatible.
Examples:
($width, $height) = @{ SDL::TTF::size_utf8($font, 'Hallo World!') }; # plain text, if your script is in utf8 or ansi-format # or ($width, $height) = @{ SDL::TTF::size_utf8($font, "\xE4\xBB\x8A\xE6\x97\xA5\xE3\x81\xAF") }; # utf8 hex-data # or use Unicode::String; my $unicode = utf8($data_from_somwhere); ($width, $height) = @{ SDL::TTF::size_utf8($font, $unicode->utf8) }; # utf8 via Unicode::String
my ($width, $height) = @{ SDL::TTF::size_unicode($font, $text) };
Calculate the resulting surface size of the UNICODE encoded text rendered using $font. No actual rendering is done, however correct kerning is done to get the actual width. The height returned in h is the same as you can get using SDL::TTF::font_height.
$text has to be:
$text
"hallo" will look like "\0h\0a\0l\0l\0o"
"hallo" will look like "\xFE\xFF\0h\0a\0l\0l\0o"
"hallo" will look like "\xFF\xFEh\0a\0l\0l\0o\0"
You may use Unicode::String for this.
my $surface = SDL::TTF::render_glyph_solid($font, $char, $color);
Render the unicode encoded char onto a new surface, using the Solid mode. After that you can blit this surface to your display-surface.
Note: The unicode char has to be passed exactly like for SDL::TTF::size_unicode.
Note: See space-character bug. You have to upgrade libfreetype2 to at least version 2.3.5
my $surface = SDL::TTF::render_text_solid($font, $text, $color);
Render the LATIN1 encoded text onto a new surface, using the Solid mode. After that you can blit this surface to your display-surface.
use SDL; use SDL::Rect; use SDL::Video; use SDL::Color; use SDL::TTF; use SDL::TTF::Font; SDL::init(SDL_INIT_VIDEO); SDL::TTF::init(); my $display = SDL::Video::set_video_mode(640, 480, 32, SDL_SWSURFACE); my $font = SDL::TTF::open_font('test/data/aircut3.ttf', '24'); die 'Coudnt make font '. SDL::get_error if !$font; my $surface = SDL::TTF::render_text_solid($font, 'Hallo!', SDL::Color->new(0xFF,0xFF,0xFF)); SDL::Video::blit_surface($surface, SDL::Rect->new(0, 0, 640, 480), $display, SDL::Rect->new(10, 10, 640, 480)); SDL::Video::update_rect($display, 0, 0, 0, 0); SDL::delay(5000);
my $surface = SDL::TTF::render_utf8_solid($font, $text, $color);
Render the UTF8 encoded text onto a new surface, using the Solid mode. After that you can blit this surface to your display-surface.
my $surface = SDL::TTF::render_unicode_solid($font, $text, $color);
Render the unicode encoded text onto a new surface, using the Solid mode. After that you can blit this surface to your display-surface.
Note: The unicode test has to be passed exactly like for SDL::TTF::size_unicode.
my $surface = SDL::TTF::render_glyph_shaded($font, $char, $color, $background_color);
Render the unicode encoded char onto a new surface. The surface is filled with $background_color. After that you can blit this surface to your display-surface.
$background_color
my $surface = SDL::TTF::render_text_shaded($font, $text, $color, $background_color);
Render the LATIN1 encoded text onto a new surface. The surface is filled with $background_color. After that you can blit this surface to your display-surface.
use SDL; use SDL::Video; use SDL::Color; use SDL::TTF; use SDL::TTF::Font; SDL::init(SDL_INIT_VIDEO); SDL::TTF::init(); my $display = SDL::Video::set_video_mode(640, 480, 32, SDL_SWSURFACE); my $font = SDL::TTF::open_font('arial.ttf', '24'); my $white = SDL::Color->new(0xFF, 0xFF, 0xFF); my $black = SDL::Color->new(0x00, 0x00, 0x00); my $surface = SDL::TTF::render_text_solid($font, 'Hallo!', $white, $black); SDL::Video::blit_surface($surface, SDL::Rect->new(0, 0, 640, 480), $display, SDL::Rect->new(10, 10, 640, 480)); SDL::Video::update_rect($display, 0, 0, 0, 0); SDL::delay(5000);
my $surface = SDL::TTF::render_utf8_shaded($font, $text, $color, $background_color);
Render the UTF8 encoded text onto a new surface. The surface is filled with $background_color. After that you can blit this surface to your display-surface.
my $surface = SDL::TTF::render_unicode_shaded($font, $text, $color, $background_color);
Render the unicode encoded text onto a new surface. The surface is filled with $background_color. After that you can blit this surface to your display-surface.
Note: The unicode text has to be passed exactly like for SDL::TTF::size_unicode.
my $surface = SDL::TTF::render_glyph_blended($font, $char, $color);
Render the unicode encoded char onto a new surface. After that you can blit this surface to your display-surface.
my $surface = SDL::TTF::render_text_blended($font, $text, $color);
Render the LATIN1 encoded text onto a new surface. After that you can blit this surface to your display-surface.
use SDL; use SDL::Video; use SDL::Color; use SDL::TTF; use SDL::TTF::Font; SDL::init(SDL_INIT_VIDEO); SDL::TTF::init(); my $display = SDL::Video::set_video_mode(640, 480, 32, SDL_SWSURFACE); my $font = SDL::TTF::open_font('arial.ttf', '24'); my $surface = SDL::TTF::render_text_blended($font, 'Hallo!', SDL::Color->new(0xFF,0xFF,0xFF)); SDL::Video::blit_surface($surface, SDL::Rect->new(0, 0, 640, 480), $display, SDL::Rect->new(10, 10, 640, 480)); SDL::Video::update_rect($display, 0, 0, 0, 0); SDL::delay(5000);
my $surface = SDL::TTF::render_utf8_blended($font, $text, $color);
Render the UTF8 encoded text onto a new surface. After that you can blit this surface to your display-surface.
my $surface = SDL::TTF::render_unicode_blended($font, $text, $color);
Render the unicode encoded text onto a new surface. After that you can blit this surface to your display-surface.
See "AUTHORS" in SDL.
SDL::TTF::Font, Unicode::String, SDL::Video, SDL::Surface
To install SDL, copy and paste the appropriate command in to your terminal.
cpanm
cpanm SDL
CPAN shell
perl -MCPAN -e shell install SDL
For more information on module installation, please visit the detailed CPAN module installation guide.