Enum AlphaPolicy 

#[non_exhaustive]
pub enum AlphaPolicy {
    DiscardIfOpaque,
    DiscardUnchecked,
    CompositeOnto {
        r: u8,
        g: u8,
        b: u8,
    },
    Forbid,
}

Policy for alpha channel removal. Required when converting from a layout with alpha to one without.

Variants (Non-exhaustive)

Non-exhaustive enums could have additional variants added in future. Therefore, when matching against variants of non-exhaustive enums, an extra wildcard arm must be added to account for any future variants.

DiscardIfOpaque

Discard only if every pixel is fully opaque. Returns error otherwise.

DiscardUnchecked

Discard unconditionally. Caller acknowledges data loss.

CompositeOnto

Composite onto solid background (values in source range, 0–255 for U8).

Fields

r: u8

Red background value.

g: u8

Green background value.

b: u8

Blue background value.

Forbid

Return error rather than dropping alpha.

Trait Implementations

impl Clone for AlphaPolicy

fn clone(&self) -> AlphaPolicy

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Debug for AlphaPolicy

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

Formats the value using the given formatter.

impl Hash for AlphaPolicy

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, Self: Sized,

Feeds a slice of this type into the given Hasher.

impl PartialEq for AlphaPolicy

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

Tests for self and other values to be equal, and is used by ==.

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

Tests for !=. The default implementation is almost always sufficient, and should not be overridden without very good reason.

impl Copy for AlphaPolicy

impl Eq for AlphaPolicy

impl StructuralPartialEq for AlphaPolicy