Struct epaint::image::ColorImage

pub struct ColorImage {
    pub size: [usize; 2],
    pub pixels: Vec<Color32>,
}

A 2D RGBA color image in RAM.

Fields

size: [usize; 2]

width, height.

pixels: Vec<Color32>

The pixels, row by row, from top to bottom.

Implementations

impl ColorImage

pub fn new(size: [usize; 2], color: Color32) -> Self

Create an image filled with the given color.

pub fn from_rgba_unmultiplied(size: [usize; 2], rgba: &[u8]) -> Self

Create a ColorImage from flat un-multiplied RGBA data.

This is usually what you want to use after having loaded an image file.

Panics if size[0] * size[1] * 4 != rgba.len().

Example using the image crate:

fn load_image_from_path(path: &std::path::Path) -> Result<egui::ColorImage, image::ImageError> {
    let image = image::io::Reader::open(path)?.decode()?;
    let size = [image.width() as _, image.height() as _];
    let image_buffer = image.to_rgba8();
    let pixels = image_buffer.as_flat_samples();
    Ok(egui::ColorImage::from_rgba_unmultiplied(
        size,
        pixels.as_slice(),
    ))
}

fn load_image_from_memory(image_data: &[u8]) -> Result<ColorImage, image::ImageError> {
    let image = image::load_from_memory(image_data)?;
    let size = [image.width() as _, image.height() as _];
    let image_buffer = image.to_rgba8();
    let pixels = image_buffer.as_flat_samples();
    Ok(ColorImage::from_rgba_unmultiplied(
        size,
        pixels.as_slice(),
    ))
}

pub fn from_rgba_premultiplied(size: [usize; 2], rgba: &[u8]) -> Self

pub fn from_gray(size: [usize; 2], gray: &[u8]) -> Self

Create a ColorImage from flat opaque gray data.

Panics if size[0] * size[1] != gray.len().

pub fn from_gray_iter( size: [usize; 2], gray_iter: impl Iterator<Item = u8>, ) -> Self

Alternative method to from_gray. Create a ColorImage from iterator over flat opaque gray data.

Panics if size[0] * size[1] != gray_iter.len().

pub fn as_raw(&self) -> &[u8]

A view of the underlying data as &[u8]

pub fn as_raw_mut(&mut self) -> &mut [u8]

A view of the underlying data as &mut [u8]

pub fn region(&self, region: &Rect, pixels_per_point: Option<f32>) -> Self

Create a new Image from a patch of the current image. This method is especially convenient for screenshotting a part of the app since region can be interpreted as screen coordinates of the entire screenshot if pixels_per_point is provided for the native application. The floats of emath::Rect are cast to usize, rounding them down in order to interpret them as indices to the image data.

Panics if region.min.x > region.max.x || region.min.y > region.max.y, or if a region larger than the image is passed.

pub fn from_rgb(size: [usize; 2], rgb: &[u8]) -> Self

Create a ColorImage from flat RGB data.

This is what you want to use after having loaded an image file (and if you are ignoring the alpha channel - considering it to always be 0xff)

Panics if size[0] * size[1] * 3 != rgb.len().

pub fn example() -> Self

An example color image, useful for tests.

pub fn width(&self) -> usize

pub fn height(&self) -> usize

Trait Implementations

impl Clone for ColorImage

fn clone(&self) -> ColorImage

Returns a copy of the value.

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

Performs copy-assignment from source.

impl Debug for ColorImage

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

Formats the value using the given formatter.

impl Default for ColorImage

fn default() -> ColorImage

Returns the “default value” for a type.

impl From<ColorImage> for ImageData

fn from(image: ColorImage) -> Self

Converts to this type from the input type.

impl Index<(usize, usize)> for ColorImage

type Output = Color32

The returned type after indexing.

fn index(&self, (x, y): (usize, usize)) -> &Color32

Performs the indexing (container[index]) operation.

impl IndexMut<(usize, usize)> for ColorImage

fn index_mut(&mut self, (x, y): (usize, usize)) -> &mut Color32

Performs the mutable indexing (container[index]) operation.

impl PartialEq for ColorImage

fn eq(&self, other: &ColorImage) -> 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 Eq for ColorImage

impl StructuralPartialEq for ColorImage