Enum ImageMask 

#[non_exhaustive]
pub enum ImageMask {
    ColorKey(ColorKey),
    Alpha {
        width: u32,
        height: u32,
        alpha: Box<[u8]>,
        stencil: bool,
    },
}

An image’s alpha, however it was expressed.

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.

ColorKey(ColorKey)

A /Mask array naming transparent sample values.

Alpha

A separate grayscale image, /SMask or a /Mask stream, at its own resolution — masks are never resolution-reduced, so a 400×400 mask stays 400×400 even beside a 50×50 base image.

Fields

width: u32

Mask width in samples.

height: u32

Mask height in samples.

alpha: Box<[u8]>

One byte per sample; 255 is opaque.

stencil: bool

Whether the mask is a /Mask stencil rather than an /SMask, which inverts its sense.

Implementations

impl ImageMask

pub fn alpha_at(&self, x: u32, y: u32) -> u8

The alpha at (x, y), or 255 when the mask does not cover it.

Trait Implementations

impl Clone for ImageMask

fn clone(&self) -> ImageMask

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Debug for ImageMask

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

Formats the value using the given formatter.

impl PartialEq for ImageMask

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

Equality operator ==.

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

Inequality operator !=.

impl StructuralPartialEq for ImageMask