Struct png::Transformations

pub struct Transformations { /* private fields */ }

Output transformations

Many flags from libpng are not yet supported. A PR discussing/adding them would be nice.

/// Discard the alpha channel
const STRIP_ALPHA         = 0x0002; // read only
/// Expand 1; 2 and 4-bit samples to bytes
const PACKING             = 0x0004; // read and write
/// Change order of packed pixels to LSB first
const PACKSWAP            = 0x0008; // read and write
/// Invert monochrome images
const INVERT_MONO         = 0x0020; // read and write
/// Normalize pixels to the sBIT depth
const SHIFT               = 0x0040; // read and write
/// Flip RGB to BGR; RGBA to BGRA
const BGR                 = 0x0080; // read and write
/// Flip RGBA to ARGB or GA to AG
const SWAP_ALPHA          = 0x0100; // read and write
/// Byte-swap 16-bit samples
const SWAP_ENDIAN         = 0x0200; // read and write
/// Change alpha from opacity to transparency
const INVERT_ALPHA        = 0x0400; // read and write
const STRIP_FILLER        = 0x0800; // write only
const STRIP_FILLER_BEFORE = 0x0800; // write only
const STRIP_FILLER_AFTER  = 0x1000; // write only
const GRAY_TO_RGB         = 0x2000; // read only
const EXPAND_16           = 0x4000; // read only
/// Similar to STRIP_16 but in libpng considering gamma?
/// Not entirely sure the documentation says it is more
/// accurate but doesn't say precisely how.
const SCALE_16            = 0x8000; // read only

Implementations

impl Transformations

pub const IDENTITY: Self = Self{bits: 0,}

No transformation

pub const STRIP_16: Self = Self{bits: 1,}

Strip 16-bit samples to 8 bits

pub const EXPAND: Self = Self{bits: 16,}

Expand paletted images to RGB; expand grayscale images of less than 8-bit depth to 8-bit depth; and expand tRNS chunks to alpha channels.

pub const fn empty() -> Self

Returns an empty set of flags.

pub const fn all() -> Self

Returns the set containing all flags.

pub const fn bits(&self) -> u32

Returns the raw value of the flags currently stored.

pub const fn from_bits(bits: u32) -> Option<Self>

Convert from underlying bit representation, unless that representation contains bits that do not correspond to a flag.

pub const fn from_bits_truncate(bits: u32) -> Self

Convert from underlying bit representation, dropping any bits that do not correspond to flags.

pub const unsafe fn from_bits_unchecked(bits: u32) -> Self

Convert from underlying bit representation, preserving all bits (even those not corresponding to a defined flag).

Safety

The caller of the bitflags! macro can chose to allow or disallow extra bits for their bitflags type.

The caller of from_bits_unchecked() has to ensure that all bits correspond to a defined flag or that extra bits are valid for this bitflags type.

pub const fn is_empty(&self) -> bool

Returns true if no flags are currently stored.

pub const fn is_all(&self) -> bool

Returns true if all flags are currently set.

pub const fn intersects(&self, other: Self) -> bool

Returns true if there are flags common to both self and other.

pub const fn contains(&self, other: Self) -> bool

Returns true if all of the flags in other are contained within self.

pub fn insert(&mut self, other: Self)

Inserts the specified flags in-place.

pub fn remove(&mut self, other: Self)

Removes the specified flags in-place.

pub fn toggle(&mut self, other: Self)

Toggles the specified flags in-place.

pub fn set(&mut self, other: Self, value: bool)

Inserts or removes the specified flags depending on the passed value.

pub const fn intersection(self, other: Self) -> Self

Returns the intersection between the flags in self and other.

Specifically, the returned set contains only the flags which are present in both self and other.

This is equivalent to using the & operator (e.g. ops::BitAnd), as in flags & other.

pub const fn union(self, other: Self) -> Self

Returns the union of between the flags in self and other.

Specifically, the returned set contains all flags which are present in either self or other, including any which are present in both (see Self::symmetric_difference if that is undesirable).

This is equivalent to using the | operator (e.g. ops::BitOr), as in flags | other.

pub const fn difference(self, other: Self) -> Self

Returns the difference between the flags in self and other.

Specifically, the returned set contains all flags present in self, except for the ones present in other.

It is also conceptually equivalent to the “bit-clear” operation: flags & !other (and this syntax is also supported).

This is equivalent to using the - operator (e.g. ops::Sub), as in flags - other.

pub const fn symmetric_difference(self, other: Self) -> Self

Returns the symmetric difference between the flags in self and other.

Specifically, the returned set contains the flags present which are present in self or other, but that are not present in both. Equivalently, it contains the flags present in exactly one of the sets self and other.

This is equivalent to using the ^ operator (e.g. ops::BitXor), as in flags ^ other.

pub const fn complement(self) -> Self

Returns the complement of this set of flags.

Specifically, the returned set contains all the flags which are not set in self, but which are allowed for this type.

Alternatively, it can be thought of as the set difference between Self::all() and self (e.g. Self::all() - self)

This is equivalent to using the ! operator (e.g. ops::Not), as in !flags.

impl Transformations

pub fn normalize_to_color8() -> Transformations

Transform every input to 8bit grayscale or color.

This sets EXPAND and STRIP_16 which is similar to the default transformation used by this library prior to 0.17.

Trait Implementations

impl Binary for Transformations

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

Formats the value using the given formatter.

impl BitAnd<Transformations> for Transformations

fn bitand(self, other: Self) -> Self

Returns the intersection between the two sets of flags.

type Output = Transformations

The resulting type after applying the & operator.

impl BitAndAssign<Transformations> for Transformations

fn bitand_assign(&mut self, other: Self)

Disables all flags disabled in the set.

impl BitOr<Transformations> for Transformations

fn bitor(self, other: Transformations) -> Self

Returns the union of the two sets of flags.

type Output = Transformations

The resulting type after applying the | operator.

impl BitOrAssign<Transformations> for Transformations

fn bitor_assign(&mut self, other: Self)

Adds the set of flags.

impl BitXor<Transformations> for Transformations

fn bitxor(self, other: Self) -> Self

Returns the left flags, but with all the right flags toggled.

type Output = Transformations

The resulting type after applying the ^ operator.

impl BitXorAssign<Transformations> for Transformations

fn bitxor_assign(&mut self, other: Self)

Toggles the set of flags.

impl Clone for Transformations

fn clone(&self) -> Transformations

Returns a copy of the value.

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

Performs copy-assignment from source.

impl Debug for Transformations

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

Formats the value using the given formatter.

impl Default for Transformations

Instantiate the default transformations, the identity transform.

fn default() -> Transformations

Returns the “default value” for a type.

impl Extend<Transformations> for Transformations

fn extend<T: IntoIterator<Item = Self>>(&mut self, iterator: T)

Extends a collection with the contents of an iterator.

fn extend_one(&mut self, item: A)

🔬 This is a nightly-only experimental API. (extend_one)

Extends a collection with exactly one element.

fn extend_reserve(&mut self, additional: usize)

🔬 This is a nightly-only experimental API. (extend_one)

Reserves capacity in a collection for the given number of additional elements.

impl FromIterator<Transformations> for Transformations

fn from_iter<T: IntoIterator<Item = Self>>(iterator: T) -> Self

Creates a value from an iterator.

impl Hash for Transformations

fn hash<__H: Hasher>(&self, state: &mut __H)

Feeds this value into the given Hasher.

fn hash_slice<H>(data: &[Self], state: &mut H) where
    H: Hasher, 

Feeds a slice of this type into the given Hasher.

impl LowerHex for Transformations

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

Formats the value using the given formatter.

impl Not for Transformations

fn not(self) -> Self

Returns the complement of this set of flags.

type Output = Transformations

The resulting type after applying the ! operator.

impl Octal for Transformations

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

Formats the value using the given formatter.

impl Ord for Transformations

fn cmp(&self, other: &Transformations) -> Ordering

This method returns an Ordering between self and other.

fn max(self, other: Self) -> Self

Compares and returns the maximum of two values.

fn min(self, other: Self) -> Self

Compares and returns the minimum of two values.

fn clamp(self, min: Self, max: Self) -> Self

Restrict a value to a certain interval.

impl PartialEq<Transformations> for Transformations

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

This method tests for self and other values to be equal, and is used by ==.

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

This method tests for !=.

impl PartialOrd<Transformations> for Transformations

fn partial_cmp(&self, other: &Transformations) -> Option<Ordering>

This method returns an ordering between self and other values if one exists.

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

This method tests less than (for self and other) and is used by the < operator.

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

This method tests less than or equal to (for self and other) and is used by the <= operator.

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

This method tests greater than (for self and other) and is used by the > operator.

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

This method tests greater than or equal to (for self and other) and is used by the >= operator.

impl Sub<Transformations> for Transformations

fn sub(self, other: Self) -> Self

Returns the set difference of the two sets of flags.

type Output = Transformations

The resulting type after applying the - operator.

impl SubAssign<Transformations> for Transformations

fn sub_assign(&mut self, other: Self)

Disables all flags enabled in the set.

impl UpperHex for Transformations

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

Formats the value using the given formatter.

impl Copy for Transformations

impl Eq for Transformations

impl StructuralEq for Transformations

impl StructuralPartialEq for Transformations