Struct TransferFunc 

pub struct TransferFunc {
    pub samples: Box<[[u8; 256]; 3]>,
    pub identity: bool,
}

Three 256-entry byte tables, one per channel.

Fields

samples: Box<[[u8; 256]; 3]>

The samples, indexed [channel][input] with channel 0 red, 1 green and 2 blue.

A consumer indexes by channel and nothing else. [oracle-bug] channel 0 holds /TR’s first element (table 58’s red), not its last; see the module note.

identity: bool

Whether every entry is its own index, in which case the function is a no-op and a renderer may skip it entirely.

Implementations

impl TransferFunc

pub fn load<R: Resolve>( obj: &Object, r: &R, cache: &mut FunctionCache, limits: &Limits, diags: &mut Diagnostics, ) -> Option<Self>

Sample a /TR or /TR2 object.

Returns None for every shape PDFium refuses: a name, a three-or-more-element array with a bad entry, or an object that is neither a function nor an array of them.

pub fn apply(&self, channel: usize, value: u8) -> u8

Apply the function to one colour byte on channel — 0 red, 1 green, 2 blue.

Trait Implementations

impl Clone for TransferFunc

fn clone(&self) -> TransferFunc

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Debug for TransferFunc

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

Formats the value using the given formatter.

impl PartialEq for TransferFunc

fn eq(&self, other: &TransferFunc) -> bool

Equality operator ==.

fn ne(&self, other: &Rhs) -> bool

Inequality operator !=.

impl StructuralPartialEq for TransferFunc