SDL::TTF - True Type Font functions (libfreetype)
TODO, TTF
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.
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.
Returns: a SDL::TTF::Font object. undef is returned on errors.
Example:
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.
Example:
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( $bool );
This function tells SDL_ttf whether UNICODE (2 bytes per character) text is generally byteswapped. A UNICODE_BOM_NATIVE or
UNICODE_BOM_SWAPPED character in a string will temporarily override this setting for the remainder of that string, however this setting
will be restored for the next one. The default mode is non-swapped, native endianness of the CPU.
SDL::TTF::get_font_style($font);
Returns: The style as a bitmask composed of the following masks:
Example:
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.
my $hinting = SDL::TTF::get_font_hinting($font);
Get the current hinting setting of the loaded font.
Note: at least SDL_ttf 2.0.10 needed
Returns the hinting type matching one of the following defined values:
SDL::TTF::set_font_hinting($font, $hinting);
Set the hinting of the loaded font. You should experiment with this setting if you know which font you are using beforehand, especially when using smaller sized fonts. If the user is selecting a font, you may wish to let them select the hinting mode for that font as well.
Note: at least SDL_ttf 2.0.10 needed
Example:
SDL::TTF::set_font_hinting($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).
Note: at least SDL_ttf 2.0.10 needed
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.
Note: at least SDL_ttf 2.0.10 needed
my $font_height = SDL::TTF::font_height($font);
my $font_ascent = SDL::TTF::font_ascent($font); like( $font_ascent, '/^[-]?\d+$/', "[font_ascent] offset from the baseline to the top of the font is $font_ascent" );
my $font_descent = SDL::TTF::font_descent($font); like( $font_descent, '/^[-]?\d+$/', "[font_descent] offset from the baseline to the bottom of the font is $font_descent" );
my $font_line_skip = SDL::TTF::font_line_skip($font); like( $font_line_skip, '/^[-]?\d+$/', "[font_line_skip] recommended spacing between lines of text is $font_line_skip" );
my $font_faces = SDL::TTF::font_faces($font); ok( $font_faces, "[font_faces] font has $font_faces faces" );
my $font_face_is_fixed_width = SDL::TTF::font_face_is_fixed_width($font); like( $font_face_is_fixed_width, '/^[01]$/', "[font_face_is_fixed_width] is $font_face_is_fixed_width" );
my $font_face_family_name = SDL::TTF::font_face_family_name($font); ok( $font_face_family_name, "[font_face_family_name] is $font_face_family_name" );
my $font_face_style_name = SDL::TTF::font_face_style_name($font); ok( $font_face_style_name, "[font_face_style_name] is $font_face_style_name" );
my @glyph_metrics = @{ SDL::TTF::glyph_metrics($font, 'M') };
is( scalar @glyph_metrics, 5, "[glyph_metrics] (minx, maxx, miny, maxy, advance) = (" . join(', ', @glyph_metrics) . ")" );
my ($width, $height) = @{ SDL::TTF::size_text($font, 'Hallo World!') };
my ($width, $height) = @{ SDL::TTF::size_utf8($font, 'Hallo World!') };
my ($width, $height) = @{ SDL::TTF::size_unicode($font, 'Hallo World!') };
Note: http://bugs.debian.org/cgi-bin/bugreport.cgi?bug=374062
Tobias Leich [FROGGS]