Struct write_fonts::tables::head::Head

pub struct Head {

    pub font_revision: Fixed,
    pub checksum_adjustment: u32,
    pub magic_number: u32,
    pub flags: u16,
    pub units_per_em: u16,
    pub created: LongDateTime,
    pub modified: LongDateTime,
    pub x_min: i16,
    pub y_min: i16,
    pub x_max: i16,
    pub y_max: i16,
    pub mac_style: u16,
    pub lowest_rec_ppem: u16,
    pub font_direction_hint: i16,
    pub index_to_loc_format: i16,
}

https://docs.microsoft.com/en-us/typography/opentype/spec/head

Fields

font_revision: Fixed

Set by font manufacturer.

checksum_adjustment: u32

To compute: set it to 0, sum the entire font as uint32, then store 0xB1B0AFBA - sum. If the font is used as a component in a font collection file, the value of this field will be invalidated by changes to the file structure and font table directory, and must be ignored.

magic_number: u32

Set to 0x5F0F3CF5.

flags: u16

See the flags enum

units_per_em: u16

Set to a value from 16 to 16384. Any value in this range is valid. In fonts that have TrueType outlines, a power of 2 is recommended as this allows performance optimizations in some rasterizers.

created: LongDateTime

Number of seconds since 12:00 midnight that started January 1st 1904 in GMT/UTC time zone.

modified: LongDateTime

Number of seconds since 12:00 midnight that started January 1st 1904 in GMT/UTC time zone.

x_min: i16

Minimum x coordinate across all glyph bounding boxes.

y_min: i16

Minimum y coordinate across all glyph bounding boxes.

x_max: i16

Maximum x coordinate across all glyph bounding boxes.

y_max: i16

Maximum y coordinate across all glyph bounding boxes.

mac_style: u16

see somewhere else

lowest_rec_ppem: u16

Smallest readable size in pixels.

font_direction_hint: i16

Deprecated (Set to 2).

index_to_loc_format: i16

0 for short offsets (Offset16), 1 for long (Offset32).

Implementations

impl Head

pub fn new( font_revision: Fixed, checksum_adjustment: u32, flags: u16, units_per_em: u16, created: LongDateTime, modified: LongDateTime, x_min: i16, y_min: i16, x_max: i16, y_max: i16, mac_style: u16, lowest_rec_ppem: u16, index_to_loc_format: i16 ) -> Self

Construct a new Head

Trait Implementations

impl Clone for Head

fn clone(&self) -> Head

Returns a copy of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Debug for Head

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl Default for Head

fn default() -> Self

Returns the “default value” for a type.

impl<'a> FontRead<'a> for Head

fn read(data: FontData<'a>) -> Result<Self, ReadError>

Read an instace of Self from the provided data, performing validation.

impl FontWrite for Head

fn write_into(&self, writer: &mut TableWriter)

Write our data and information about offsets into this TableWriter.

impl TopLevelTable for Head

const TAG: Tag = _

The table’s tag.

impl Validate for Head

fn validate_impl(&self, _ctx: &mut ValidationCtx)

Validate this table.

fn validate(&self) -> Result<(), ValidationReport>

Ensure that this table is well-formed, reporting any errors.