Struct Image

pub struct Image {
    pub data: Vec<u8>,
    pub texture_descriptor: TextureDescriptor<Option<&'static str>, &'static [TextureFormat]>,
    pub sampler: ImageSampler,
    pub texture_view_descriptor: Option<TextureViewDescriptor<'static>>,
    pub asset_usage: RenderAssetUsages,
}

Fields

data: Vec<u8>

texture_descriptor: TextureDescriptor<Option<&'static str>, &'static [TextureFormat]>

sampler: ImageSampler

The ImageSampler to use during rendering.

texture_view_descriptor: Option<TextureViewDescriptor<'static>>

asset_usage: RenderAssetUsages

Implementations

impl Image

pub fn new( size: Extent3d, dimension: TextureDimension, data: Vec<u8>, format: TextureFormat, asset_usage: RenderAssetUsages, ) -> Image

Creates a new image from raw binary data and the corresponding metadata.

Panics

Panics if the length of the data, volume of the size and the size of the format do not match.

pub fn transparent() -> Image

A transparent white 1x1x1 image.

Contrast to Image::default, which is opaque.

pub fn new_fill( size: Extent3d, dimension: TextureDimension, pixel: &[u8], format: TextureFormat, asset_usage: RenderAssetUsages, ) -> Image

Creates a new image from raw binary data and the corresponding metadata, by filling the image data with the pixel data repeated multiple times.

Panics

Panics if the size of the format is not a multiple of the length of the pixel data.

Examples found in repository

examples/3d/3d_shapes.rs (lines 169-179)

fn uv_debug_texture() -> Image {
    const TEXTURE_SIZE: usize = 8;

    let mut palette: [u8; 32] = [
        255, 102, 159, 255, 255, 159, 102, 255, 236, 255, 102, 255, 121, 255, 102, 255, 102, 255,
        198, 255, 102, 198, 255, 255, 121, 102, 255, 255, 236, 102, 255, 255,
    ];

    let mut texture_data = [0; TEXTURE_SIZE * TEXTURE_SIZE * 4];
    for y in 0..TEXTURE_SIZE {
        let offset = TEXTURE_SIZE * y * 4;
        texture_data[offset..(offset + TEXTURE_SIZE * 4)].copy_from_slice(&palette);
        palette.rotate_right(4);
    }

    Image::new_fill(
        Extent3d {
            width: TEXTURE_SIZE as u32,
            height: TEXTURE_SIZE as u32,
            depth_or_array_layers: 1,
        },
        TextureDimension::D2,
        &texture_data,
        TextureFormat::Rgba8UnormSrgb,
        RenderAssetUsages::RENDER_WORLD,
    )
}

examples/stress_tests/bevymark.rs (lines 574-584)

fn init_textures(textures: &mut Vec<Handle<Image>>, args: &Args, images: &mut Assets<Image>) {
    // We're seeding the PRNG here to make this example deterministic for testing purposes.
    // This isn't strictly required in practical use unless you need your app to be deterministic.
    let mut color_rng = ChaCha8Rng::seed_from_u64(42);
    while textures.len() < args.material_texture_count {
        let pixel = [color_rng.gen(), color_rng.gen(), color_rng.gen(), 255];
        textures.push(images.add(Image::new_fill(
            Extent3d {
                width: BIRD_TEXTURE_SIZE as u32,
                height: BIRD_TEXTURE_SIZE as u32,
                depth_or_array_layers: 1,
            },
            TextureDimension::D2,
            &pixel,
            TextureFormat::Rgba8UnormSrgb,
            RenderAssetUsages::RENDER_WORLD,
        )));
    }
}

examples/stress_tests/many_cubes.rs (lines 263-273)

fn init_textures(args: &Args, images: &mut Assets<Image>) -> Vec<Handle<Image>> {
    // We're seeding the PRNG here to make this example deterministic for testing purposes.
    // This isn't strictly required in practical use unless you need your app to be deterministic.
    let mut color_rng = ChaCha8Rng::seed_from_u64(42);
    let color_bytes: Vec<u8> = (0..(args.material_texture_count * 4))
        .map(|i| if (i % 4) == 3 { 255 } else { color_rng.gen() })
        .collect();
    color_bytes
        .chunks(4)
        .map(|pixel| {
            images.add(Image::new_fill(
                Extent3d {
                    width: 1,
                    height: 1,
                    depth_or_array_layers: 1,
                },
                TextureDimension::D2,
                pixel,
                TextureFormat::Rgba8UnormSrgb,
                RenderAssetUsages::RENDER_WORLD,
            ))
        })
        .collect()
}

examples/3d/anti_aliasing.rs (lines 362-372)

fn uv_debug_texture() -> Image {
    const TEXTURE_SIZE: usize = 8;

    let mut palette: [u8; 32] = [
        255, 102, 159, 255, 255, 159, 102, 255, 236, 255, 102, 255, 121, 255, 102, 255, 102, 255,
        198, 255, 102, 198, 255, 255, 121, 102, 255, 255, 236, 102, 255, 255,
    ];

    let mut texture_data = [0; TEXTURE_SIZE * TEXTURE_SIZE * 4];
    for y in 0..TEXTURE_SIZE {
        let offset = TEXTURE_SIZE * y * 4;
        texture_data[offset..(offset + TEXTURE_SIZE * 4)].copy_from_slice(&palette);
        palette.rotate_right(4);
    }

    let mut img = Image::new_fill(
        Extent3d {
            width: TEXTURE_SIZE as u32,
            height: TEXTURE_SIZE as u32,
            depth_or_array_layers: 1,
        },
        TextureDimension::D2,
        &texture_data,
        TextureFormat::Rgba8UnormSrgb,
        RenderAssetUsages::RENDER_WORLD,
    );
    img.sampler = ImageSampler::Descriptor(ImageSamplerDescriptor::default());
    img
}

examples/shader/compute_shader_game_of_life.rs (lines 54-64)

fn setup(mut commands: Commands, mut images: ResMut<Assets<Image>>) {
    let mut image = Image::new_fill(
        Extent3d {
            width: SIZE.0,
            height: SIZE.1,
            depth_or_array_layers: 1,
        },
        TextureDimension::D2,
        &[0, 0, 0, 255],
        TextureFormat::R32Float,
        RenderAssetUsages::RENDER_WORLD,
    );
    image.texture_descriptor.usage =
        TextureUsages::COPY_DST | TextureUsages::STORAGE_BINDING | TextureUsages::TEXTURE_BINDING;
    let image0 = images.add(image.clone());
    let image1 = images.add(image);

    commands.spawn((
        Sprite {
            image: image0.clone(),
            custom_size: Some(Vec2::new(SIZE.0 as f32, SIZE.1 as f32)),
            ..default()
        },
        Transform::from_scale(Vec3::splat(DISPLAY_FACTOR as f32)),
    ));
    commands.spawn(Camera2d);

    commands.insert_resource(GameOfLifeImages {
        texture_a: image0,
        texture_b: image1,
    });
}

examples/3d/motion_blur.rs (lines 373-383)

fn uv_debug_texture() -> Image {
    use bevy::render::{render_asset::RenderAssetUsages, render_resource::*};
    const TEXTURE_SIZE: usize = 7;

    let mut palette = [
        164, 164, 164, 255, 168, 168, 168, 255, 153, 153, 153, 255, 139, 139, 139, 255, 153, 153,
        153, 255, 177, 177, 177, 255, 159, 159, 159, 255,
    ];

    let mut texture_data = [0; TEXTURE_SIZE * TEXTURE_SIZE * 4];
    for y in 0..TEXTURE_SIZE {
        let offset = TEXTURE_SIZE * y * 4;
        texture_data[offset..(offset + TEXTURE_SIZE * 4)].copy_from_slice(&palette);
        palette.rotate_right(12);
    }

    let mut img = Image::new_fill(
        Extent3d {
            width: TEXTURE_SIZE as u32,
            height: TEXTURE_SIZE as u32,
            depth_or_array_layers: 1,
        },
        TextureDimension::D2,
        &texture_data,
        TextureFormat::Rgba8UnormSrgb,
        RenderAssetUsages::RENDER_WORLD,
    );
    img.sampler = ImageSampler::Descriptor(ImageSamplerDescriptor {
        address_mode_u: ImageAddressMode::Repeat,
        address_mode_v: ImageAddressMode::MirrorRepeat,
        mag_filter: ImageFilterMode::Nearest,
        ..ImageSamplerDescriptor::linear()
    });
    img
}

Additional examples can be found in:

• examples/app/headless_renderer.rs
• examples/2d/cpu_draw.rs
• examples/shader/gpu_readback.rs
• examples/ui/render_ui_to_texture.rs
• examples/3d/render_to_texture.rs

pub fn width(&self) -> u32

Returns the width of a 2D image.

Examples found in repository

examples/3d/skybox.rs (line 154)

fn asset_loaded(
    asset_server: Res<AssetServer>,
    mut images: ResMut<Assets<Image>>,
    mut cubemap: ResMut<Cubemap>,
    mut skyboxes: Query<&mut Skybox>,
) {
    if !cubemap.is_loaded && asset_server.load_state(&cubemap.image_handle).is_loaded() {
        info!("Swapping to {}...", CUBEMAPS[cubemap.index].0);
        let image = images.get_mut(&cubemap.image_handle).unwrap();
        // NOTE: PNGs do not have any metadata that could indicate they contain a cubemap texture,
        // so they appear as one texture. The following code reconfigures the texture as necessary.
        if image.texture_descriptor.array_layer_count() == 1 {
            image.reinterpret_stacked_2d_as_array(image.height() / image.width());
            image.texture_view_descriptor = Some(TextureViewDescriptor {
                dimension: Some(TextureViewDimension::Cube),
                ..default()
            });
        }

        for mut skybox in &mut skyboxes {
            skybox.image = cubemap.image_handle.clone();
        }

        cubemap.is_loaded = true;
    }
}

examples/app/headless_renderer.rs (line 499)

fn update(
    images_to_save: Query<&ImageToSave>,
    receiver: Res<MainWorldReceiver>,
    mut images: ResMut<Assets<Image>>,
    mut scene_controller: ResMut<SceneController>,
    mut app_exit_writer: EventWriter<AppExit>,
    mut file_number: Local<u32>,
) {
    if let SceneState::Render(n) = scene_controller.state {
        if n < 1 {
            // We don't want to block the main world on this,
            // so we use try_recv which attempts to receive without blocking
            let mut image_data = Vec::new();
            while let Ok(data) = receiver.try_recv() {
                // image generation could be faster than saving to fs,
                // that's why use only last of them
                image_data = data;
            }
            if !image_data.is_empty() {
                for image in images_to_save.iter() {
                    // Fill correct data from channel to image
                    let img_bytes = images.get_mut(image.id()).unwrap();

                    // We need to ensure that this works regardless of the image dimensions
                    // If the image became wider when copying from the texture to the buffer,
                    // then the data is reduced to its original size when copying from the buffer to the image.
                    let row_bytes = img_bytes.width() as usize
                        * img_bytes.texture_descriptor.format.pixel_size();
                    let aligned_row_bytes = RenderDevice::align_copy_bytes_per_row(row_bytes);
                    if row_bytes == aligned_row_bytes {
                        img_bytes.data.clone_from(&image_data);
                    } else {
                        // shrink data to original image size
                        img_bytes.data = image_data
                            .chunks(aligned_row_bytes)
                            .take(img_bytes.height() as usize)
                            .flat_map(|row| &row[..row_bytes.min(row.len())])
                            .cloned()
                            .collect();
                    }

                    // Create RGBA Image Buffer
                    let img = match img_bytes.clone().try_into_dynamic() {
                        Ok(img) => img.to_rgba8(),
                        Err(e) => panic!("Failed to create image buffer {e:?}"),
                    };

                    // Prepare directory for images, test_images in bevy folder is used here for example
                    // You should choose the path depending on your needs
                    let images_dir = PathBuf::from(env!("CARGO_MANIFEST_DIR")).join("test_images");
                    info!("Saving image to: {images_dir:?}");
                    std::fs::create_dir_all(&images_dir).unwrap();

                    // Choose filename starting from 000.png
                    let image_path = images_dir.join(format!("{:03}.png", file_number.deref()));
                    *file_number.deref_mut() += 1;

                    // Finally saving image to file, this heavy blocking operation is kept here
                    // for example simplicity, but in real app you should move it to a separate task
                    if let Err(e) = img.save(image_path) {
                        panic!("Failed to save image: {e}");
                    };
                }
                if scene_controller.single_image {
                    app_exit_writer.send(AppExit::Success);
                }
            }
        } else {
            // clears channel for skipped frames
            while receiver.try_recv().is_ok() {}
            scene_controller.state = SceneState::Render(n - 1);
        }
    }
}

pub fn height(&self) -> u32

Returns the height of a 2D image.

Examples found in repository

examples/3d/skybox.rs (line 154)

fn asset_loaded(
    asset_server: Res<AssetServer>,
    mut images: ResMut<Assets<Image>>,
    mut cubemap: ResMut<Cubemap>,
    mut skyboxes: Query<&mut Skybox>,
) {
    if !cubemap.is_loaded && asset_server.load_state(&cubemap.image_handle).is_loaded() {
        info!("Swapping to {}...", CUBEMAPS[cubemap.index].0);
        let image = images.get_mut(&cubemap.image_handle).unwrap();
        // NOTE: PNGs do not have any metadata that could indicate they contain a cubemap texture,
        // so they appear as one texture. The following code reconfigures the texture as necessary.
        if image.texture_descriptor.array_layer_count() == 1 {
            image.reinterpret_stacked_2d_as_array(image.height() / image.width());
            image.texture_view_descriptor = Some(TextureViewDescriptor {
                dimension: Some(TextureViewDimension::Cube),
                ..default()
            });
        }

        for mut skybox in &mut skyboxes {
            skybox.image = cubemap.image_handle.clone();
        }

        cubemap.is_loaded = true;
    }
}

examples/app/headless_renderer.rs (line 508)

fn update(
    images_to_save: Query<&ImageToSave>,
    receiver: Res<MainWorldReceiver>,
    mut images: ResMut<Assets<Image>>,
    mut scene_controller: ResMut<SceneController>,
    mut app_exit_writer: EventWriter<AppExit>,
    mut file_number: Local<u32>,
) {
    if let SceneState::Render(n) = scene_controller.state {
        if n < 1 {
            // We don't want to block the main world on this,
            // so we use try_recv which attempts to receive without blocking
            let mut image_data = Vec::new();
            while let Ok(data) = receiver.try_recv() {
                // image generation could be faster than saving to fs,
                // that's why use only last of them
                image_data = data;
            }
            if !image_data.is_empty() {
                for image in images_to_save.iter() {
                    // Fill correct data from channel to image
                    let img_bytes = images.get_mut(image.id()).unwrap();

                    // We need to ensure that this works regardless of the image dimensions
                    // If the image became wider when copying from the texture to the buffer,
                    // then the data is reduced to its original size when copying from the buffer to the image.
                    let row_bytes = img_bytes.width() as usize
                        * img_bytes.texture_descriptor.format.pixel_size();
                    let aligned_row_bytes = RenderDevice::align_copy_bytes_per_row(row_bytes);
                    if row_bytes == aligned_row_bytes {
                        img_bytes.data.clone_from(&image_data);
                    } else {
                        // shrink data to original image size
                        img_bytes.data = image_data
                            .chunks(aligned_row_bytes)
                            .take(img_bytes.height() as usize)
                            .flat_map(|row| &row[..row_bytes.min(row.len())])
                            .cloned()
                            .collect();
                    }

                    // Create RGBA Image Buffer
                    let img = match img_bytes.clone().try_into_dynamic() {
                        Ok(img) => img.to_rgba8(),
                        Err(e) => panic!("Failed to create image buffer {e:?}"),
                    };

                    // Prepare directory for images, test_images in bevy folder is used here for example
                    // You should choose the path depending on your needs
                    let images_dir = PathBuf::from(env!("CARGO_MANIFEST_DIR")).join("test_images");
                    info!("Saving image to: {images_dir:?}");
                    std::fs::create_dir_all(&images_dir).unwrap();

                    // Choose filename starting from 000.png
                    let image_path = images_dir.join(format!("{:03}.png", file_number.deref()));
                    *file_number.deref_mut() += 1;

                    // Finally saving image to file, this heavy blocking operation is kept here
                    // for example simplicity, but in real app you should move it to a separate task
                    if let Err(e) = img.save(image_path) {
                        panic!("Failed to save image: {e}");
                    };
                }
                if scene_controller.single_image {
                    app_exit_writer.send(AppExit::Success);
                }
            }
        } else {
            // clears channel for skipped frames
            while receiver.try_recv().is_ok() {}
            scene_controller.state = SceneState::Render(n - 1);
        }
    }
}

pub fn aspect_ratio(&self) -> AspectRatio

Returns the aspect ratio (width / height) of a 2D image.

pub fn size_f32(&self) -> Vec2

Returns the size of a 2D image as f32.

Examples found in repository

examples/3d/tonemapping.rs (line 251)

fn resize_image(
    image_mesh: Query<(&MeshMaterial3d<StandardMaterial>, &Mesh3d), With<HDRViewer>>,
    materials: Res<Assets<StandardMaterial>>,
    mut meshes: ResMut<Assets<Mesh>>,
    images: Res<Assets<Image>>,
    mut image_events: EventReader<AssetEvent<Image>>,
) {
    for event in image_events.read() {
        let (AssetEvent::Added { id } | AssetEvent::Modified { id }) = event else {
            continue;
        };

        for (mat_h, mesh_h) in &image_mesh {
            let Some(mat) = materials.get(mat_h) else {
                continue;
            };

            let Some(ref base_color_texture) = mat.base_color_texture else {
                continue;
            };

            if *id != base_color_texture.id() {
                continue;
            };

            let Some(image_changed) = images.get(*id) else {
                continue;
            };

            let size = image_changed.size_f32().normalize_or_zero() * 1.4;
            // Resize Mesh
            let quad = Mesh::from(Rectangle::from_size(size));
            meshes.insert(mesh_h, quad);
        }
    }
}

pub fn size(&self) -> UVec2

Returns the size of a 2D image.

pub fn resize(&mut self, size: Extent3d)

Resizes the image to the new size, by removing information or appending 0 to the data. Does not properly resize the contents of the image, but only its internal data buffer.

Examples found in repository

examples/2d/pixel_grid_snap.rs (line 110)

fn setup_camera(mut commands: Commands, mut images: ResMut<Assets<Image>>) {
    let canvas_size = Extent3d {
        width: RES_WIDTH,
        height: RES_HEIGHT,
        ..default()
    };

    // this Image serves as a canvas representing the low-resolution game screen
    let mut canvas = Image {
        texture_descriptor: TextureDescriptor {
            label: None,
            size: canvas_size,
            dimension: TextureDimension::D2,
            format: TextureFormat::Bgra8UnormSrgb,
            mip_level_count: 1,
            sample_count: 1,
            usage: TextureUsages::TEXTURE_BINDING
                | TextureUsages::COPY_DST
                | TextureUsages::RENDER_ATTACHMENT,
            view_formats: &[],
        },
        ..default()
    };

    // fill image.data with zeroes
    canvas.resize(canvas_size);

    let image_handle = images.add(canvas);

    // this camera renders whatever is on `PIXEL_PERFECT_LAYERS` to the canvas
    commands.spawn((
        Camera2d,
        Camera {
            // render before the "main pass" camera
            order: -1,
            target: RenderTarget::Image(image_handle.clone()),
            ..default()
        },
        Msaa::Off,
        InGameCamera,
        PIXEL_PERFECT_LAYERS,
    ));

    // spawn the canvas
    commands.spawn((Sprite::from_image(image_handle), Canvas, HIGH_RES_LAYERS));

    // the "outer" camera renders whatever is on `HIGH_RES_LAYERS` to the screen.
    // here, the canvas and one of the sample sprites will be rendered by this camera
    commands.spawn((Camera2d, Msaa::Off, OuterCamera, HIGH_RES_LAYERS));
}

pub fn reinterpret_size(&mut self, new_size: Extent3d)

Changes the size, asserting that the total number of data elements (pixels) remains the same.

Panics

Panics if the new_size does not have the same volume as to old one.

pub fn reinterpret_stacked_2d_as_array(&mut self, layers: u32)

Takes a 2D image containing vertically stacked images of the same size, and reinterprets it as a 2D array texture, where each of the stacked images becomes one layer of the array. This is primarily for use with the texture2DArray shader uniform type.

Panics

Panics if the texture is not 2D, has more than one layers or is not evenly dividable into the layers.

Examples found in repository

examples/3d/skybox.rs (line 154)

fn asset_loaded(
    asset_server: Res<AssetServer>,
    mut images: ResMut<Assets<Image>>,
    mut cubemap: ResMut<Cubemap>,
    mut skyboxes: Query<&mut Skybox>,
) {
    if !cubemap.is_loaded && asset_server.load_state(&cubemap.image_handle).is_loaded() {
        info!("Swapping to {}...", CUBEMAPS[cubemap.index].0);
        let image = images.get_mut(&cubemap.image_handle).unwrap();
        // NOTE: PNGs do not have any metadata that could indicate they contain a cubemap texture,
        // so they appear as one texture. The following code reconfigures the texture as necessary.
        if image.texture_descriptor.array_layer_count() == 1 {
            image.reinterpret_stacked_2d_as_array(image.height() / image.width());
            image.texture_view_descriptor = Some(TextureViewDescriptor {
                dimension: Some(TextureViewDimension::Cube),
                ..default()
            });
        }

        for mut skybox in &mut skyboxes {
            skybox.image = cubemap.image_handle.clone();
        }

        cubemap.is_loaded = true;
    }
}

examples/shader/array_texture.rs (line 70)

fn create_array_texture(
    mut commands: Commands,
    asset_server: Res<AssetServer>,
    mut loading_texture: ResMut<LoadingTexture>,
    mut images: ResMut<Assets<Image>>,
    mut meshes: ResMut<Assets<Mesh>>,
    mut materials: ResMut<Assets<ArrayTextureMaterial>>,
) {
    if loading_texture.is_loaded
        || !asset_server
            .load_state(loading_texture.handle.id())
            .is_loaded()
    {
        return;
    }
    loading_texture.is_loaded = true;
    let image = images.get_mut(&loading_texture.handle).unwrap();

    // Create a new array texture asset from the loaded texture.
    let array_layers = 4;
    image.reinterpret_stacked_2d_as_array(array_layers);

    // Spawn some cubes using the array texture
    let mesh_handle = meshes.add(Cuboid::default());
    let material_handle = materials.add(ArrayTextureMaterial {
        array_texture: loading_texture.handle.clone(),
    });
    for x in -5..=5 {
        commands.spawn((
            Mesh3d(mesh_handle.clone()),
            MeshMaterial3d(material_handle.clone()),
            Transform::from_xyz(x as f32 + 0.5, 0.0, 0.0),
        ));
    }
}

pub fn convert(&self, new_format: TextureFormat) -> Option<Image>

Convert a texture from a format to another. Only a few formats are supported as input and output:

• TextureFormat::R8Unorm
• TextureFormat::Rg8Unorm
• TextureFormat::Rgba8UnormSrgb

To get Image as a image::DynamicImage see: Image::try_into_dynamic.

pub fn from_buffer( name: String, buffer: &[u8], image_type: ImageType<'_>, supported_compressed_formats: CompressedImageFormats, is_srgb: bool, image_sampler: ImageSampler, asset_usage: RenderAssetUsages, ) -> Result<Image, TextureError>

Load a bytes buffer in a Image, according to type image_type, using the image crate

pub fn is_compressed(&self) -> bool

Whether the texture format is compressed or uncompressed

pub fn pixel_data_offset(&self, coords: UVec3) -> Option<usize>

Compute the byte offset where the data of a specific pixel is stored

Returns None if the provided coordinates are out of bounds.

For 2D textures, Z is ignored. For 1D textures, Y and Z are ignored.

pub fn pixel_bytes(&self, coords: UVec3) -> Option<&[u8]>

Get a reference to the data bytes where a specific pixel’s value is stored

pub fn pixel_bytes_mut(&mut self, coords: UVec3) -> Option<&mut [u8]>

Get a mutable reference to the data bytes where a specific pixel’s value is stored

Examples found in repository

examples/2d/cpu_draw.rs (line 69)

fn setup(mut commands: Commands, mut images: ResMut<Assets<Image>>) {
    // spawn a camera
    commands.spawn(Camera2d);

    // create an image that we are going to draw into
    let mut image = Image::new_fill(
        // 2D image of size 256x256
        Extent3d {
            width: IMAGE_WIDTH,
            height: IMAGE_HEIGHT,
            depth_or_array_layers: 1,
        },
        TextureDimension::D2,
        // Initialize it with a beige color
        &(css::BEIGE.to_u8_array()),
        // Use the same encoding as the color we set
        TextureFormat::Rgba8UnormSrgb,
        RenderAssetUsages::MAIN_WORLD | RenderAssetUsages::RENDER_WORLD,
    );

    // to make it extra fancy, we can set the Alpha of each pixel
    // so that it fades out in a circular fashion
    for y in 0..IMAGE_HEIGHT {
        for x in 0..IMAGE_WIDTH {
            let center = Vec2::new(IMAGE_WIDTH as f32 / 2.0, IMAGE_HEIGHT as f32 / 2.0);
            let max_radius = IMAGE_HEIGHT.min(IMAGE_WIDTH) as f32 / 2.0;
            let r = Vec2::new(x as f32, y as f32).distance(center);
            let a = 1.0 - (r / max_radius).clamp(0.0, 1.0);

            // here we will set the A value by accessing the raw data bytes
            // (it is the 4th byte of each pixel, as per our `TextureFormat`)

            // find our pixel by its coordinates
            let pixel_bytes = image.pixel_bytes_mut(UVec3::new(x, y, 0)).unwrap();
            // convert our f32 to u8
            pixel_bytes[3] = (a * u8::MAX as f32) as u8;
        }
    }

    // add it to Bevy's assets, so it can be used for rendering
    // this will give us a handle we can use
    // (to display it in a sprite, or as part of UI, etc.)
    let handle = images.add(image);

    // create a sprite entity using our image
    commands.spawn(Sprite::from_image(handle.clone()));
    commands.insert_resource(MyProcGenImage(handle));
}

pub fn get_color_at_1d(&self, x: u32) -> Result<Color, TextureAccessError>

Read the color of a specific pixel (1D texture).

See get_color_at for more details.

pub fn get_color_at(&self, x: u32, y: u32) -> Result<Color, TextureAccessError>

Read the color of a specific pixel (2D texture).

This function will find the raw byte data of a specific pixel and decode it into a user-friendly Color struct for you.

Supports many of the common TextureFormats:

• RGBA/BGRA 8-bit unsigned integer, both sRGB and Linear
• 16-bit and 32-bit unsigned integer
• 32-bit float

Be careful: as the data is converted to Color (which uses f32 internally), there may be issues with precision when using non-float TextureFormats. If you read a value you previously wrote using set_color_at, it will not match. If you are working with a 32-bit integer TextureFormat, the value will be inaccurate (as f32 does not have enough bits to represent it exactly).

Single channel (R) formats are assumed to represent grayscale, so the value will be copied to all three RGB channels in the resulting Color.

Other TextureFormats are unsupported, such as:

• block-compressed formats
• non-byte-aligned formats like 10-bit
• 16-bit float formats
• signed integer formats

Examples found in repository

examples/2d/cpu_draw.rs (line 115)

fn draw(
    my_handle: Res<MyProcGenImage>,
    mut images: ResMut<Assets<Image>>,
    // used to keep track of where we are
    mut i: Local<u32>,
    mut draw_color: Local<Color>,
) {
    let mut rng = rand::thread_rng();

    if *i == 0 {
        // Generate a random color on first run.
        *draw_color = Color::linear_rgb(rng.gen(), rng.gen(), rng.gen());
    }

    // Get the image from Bevy's asset storage.
    let image = images.get_mut(&my_handle.0).expect("Image not found");

    // Compute the position of the pixel to draw.

    let center = Vec2::new(IMAGE_WIDTH as f32 / 2.0, IMAGE_HEIGHT as f32 / 2.0);
    let max_radius = IMAGE_HEIGHT.min(IMAGE_WIDTH) as f32 / 2.0;
    let rot_speed = 0.0123;
    let period = 0.12345;

    let r = ops::sin(*i as f32 * period) * max_radius;
    let xy = Vec2::from_angle(*i as f32 * rot_speed) * r + center;
    let (x, y) = (xy.x as u32, xy.y as u32);

    // Get the old color of that pixel.
    let old_color = image.get_color_at(x, y).unwrap();

    // If the old color is our current color, change our drawing color.
    let tolerance = 1.0 / 255.0;
    if old_color.distance(&draw_color) <= tolerance {
        *draw_color = Color::linear_rgb(rng.gen(), rng.gen(), rng.gen());
    }

    // Set the new color, but keep old alpha value from image.
    image
        .set_color_at(x, y, draw_color.with_alpha(old_color.alpha()))
        .unwrap();

    *i += 1;
}

pub fn get_color_at_3d( &self, x: u32, y: u32, z: u32, ) -> Result<Color, TextureAccessError>

Read the color of a specific pixel (3D texture).

See get_color_at for more details.

pub fn set_color_at_1d( &mut self, x: u32, color: Color, ) -> Result<(), TextureAccessError>

Change the color of a specific pixel (1D texture).

See set_color_at for more details.

pub fn set_color_at( &mut self, x: u32, y: u32, color: Color, ) -> Result<(), TextureAccessError>

Change the color of a specific pixel (2D texture).

This function will find the raw byte data of a specific pixel and change it according to a Color you provide. The Color struct will be encoded into the Image’s TextureFormat.

Supports many of the common TextureFormats:

• RGBA/BGRA 8-bit unsigned integer, both sRGB and Linear
• 16-bit and 32-bit unsigned integer (with possibly-limited precision, as Color uses f32)
• 32-bit float

Be careful: writing to non-float TextureFormats is lossy! The data has to be converted, so if you read it back using get_color_at, the Color you get will not equal the value you used when writing it using this function.

For R and RG formats, only the respective values from the linear RGB Color will be used.

Other TextureFormats are unsupported, such as:

• block-compressed formats
• non-byte-aligned formats like 10-bit
• 16-bit float formats
• signed integer formats

Examples found in repository

examples/2d/cpu_draw.rs (line 125)

fn draw(
    my_handle: Res<MyProcGenImage>,
    mut images: ResMut<Assets<Image>>,
    // used to keep track of where we are
    mut i: Local<u32>,
    mut draw_color: Local<Color>,
) {
    let mut rng = rand::thread_rng();

    if *i == 0 {
        // Generate a random color on first run.
        *draw_color = Color::linear_rgb(rng.gen(), rng.gen(), rng.gen());
    }

    // Get the image from Bevy's asset storage.
    let image = images.get_mut(&my_handle.0).expect("Image not found");

    // Compute the position of the pixel to draw.

    let center = Vec2::new(IMAGE_WIDTH as f32 / 2.0, IMAGE_HEIGHT as f32 / 2.0);
    let max_radius = IMAGE_HEIGHT.min(IMAGE_WIDTH) as f32 / 2.0;
    let rot_speed = 0.0123;
    let period = 0.12345;

    let r = ops::sin(*i as f32 * period) * max_radius;
    let xy = Vec2::from_angle(*i as f32 * rot_speed) * r + center;
    let (x, y) = (xy.x as u32, xy.y as u32);

    // Get the old color of that pixel.
    let old_color = image.get_color_at(x, y).unwrap();

    // If the old color is our current color, change our drawing color.
    let tolerance = 1.0 / 255.0;
    if old_color.distance(&draw_color) <= tolerance {
        *draw_color = Color::linear_rgb(rng.gen(), rng.gen(), rng.gen());
    }

    // Set the new color, but keep old alpha value from image.
    image
        .set_color_at(x, y, draw_color.with_alpha(old_color.alpha()))
        .unwrap();

    *i += 1;
}

pub fn set_color_at_3d( &mut self, x: u32, y: u32, z: u32, color: Color, ) -> Result<(), TextureAccessError>

Change the color of a specific pixel (3D texture).

See set_color_at for more details.

impl Image

pub fn from_dynamic( dyn_img: DynamicImage, is_srgb: bool, asset_usage: RenderAssetUsages, ) -> Image

Converts a DynamicImage to an Image.

pub fn try_into_dynamic(self) -> Result<DynamicImage, IntoDynamicImageError>

Convert a Image to a DynamicImage. Useful for editing image data. Not all TextureFormat are covered, therefore it will return an error if the format is unsupported. Supported formats are:

• TextureFormat::R8Unorm
• TextureFormat::Rg8Unorm
• TextureFormat::Rgba8UnormSrgb
• TextureFormat::Bgra8UnormSrgb

To convert Image to a different format see: Image::convert.

Examples found in repository

examples/app/headless_renderer.rs (line 515)

fn update(
    images_to_save: Query<&ImageToSave>,
    receiver: Res<MainWorldReceiver>,
    mut images: ResMut<Assets<Image>>,
    mut scene_controller: ResMut<SceneController>,
    mut app_exit_writer: EventWriter<AppExit>,
    mut file_number: Local<u32>,
) {
    if let SceneState::Render(n) = scene_controller.state {
        if n < 1 {
            // We don't want to block the main world on this,
            // so we use try_recv which attempts to receive without blocking
            let mut image_data = Vec::new();
            while let Ok(data) = receiver.try_recv() {
                // image generation could be faster than saving to fs,
                // that's why use only last of them
                image_data = data;
            }
            if !image_data.is_empty() {
                for image in images_to_save.iter() {
                    // Fill correct data from channel to image
                    let img_bytes = images.get_mut(image.id()).unwrap();

                    // We need to ensure that this works regardless of the image dimensions
                    // If the image became wider when copying from the texture to the buffer,
                    // then the data is reduced to its original size when copying from the buffer to the image.
                    let row_bytes = img_bytes.width() as usize
                        * img_bytes.texture_descriptor.format.pixel_size();
                    let aligned_row_bytes = RenderDevice::align_copy_bytes_per_row(row_bytes);
                    if row_bytes == aligned_row_bytes {
                        img_bytes.data.clone_from(&image_data);
                    } else {
                        // shrink data to original image size
                        img_bytes.data = image_data
                            .chunks(aligned_row_bytes)
                            .take(img_bytes.height() as usize)
                            .flat_map(|row| &row[..row_bytes.min(row.len())])
                            .cloned()
                            .collect();
                    }

                    // Create RGBA Image Buffer
                    let img = match img_bytes.clone().try_into_dynamic() {
                        Ok(img) => img.to_rgba8(),
                        Err(e) => panic!("Failed to create image buffer {e:?}"),
                    };

                    // Prepare directory for images, test_images in bevy folder is used here for example
                    // You should choose the path depending on your needs
                    let images_dir = PathBuf::from(env!("CARGO_MANIFEST_DIR")).join("test_images");
                    info!("Saving image to: {images_dir:?}");
                    std::fs::create_dir_all(&images_dir).unwrap();

                    // Choose filename starting from 000.png
                    let image_path = images_dir.join(format!("{:03}.png", file_number.deref()));
                    *file_number.deref_mut() += 1;

                    // Finally saving image to file, this heavy blocking operation is kept here
                    // for example simplicity, but in real app you should move it to a separate task
                    if let Err(e) = img.save(image_path) {
                        panic!("Failed to save image: {e}");
                    };
                }
                if scene_controller.single_image {
                    app_exit_writer.send(AppExit::Success);
                }
            }
        } else {
            // clears channel for skipped frames
            while receiver.try_recv().is_ok() {}
            scene_controller.state = SceneState::Render(n - 1);
        }
    }
}

Trait Implementations

impl Clone for Image

fn clone(&self) -> Image

Returns a copy of the value.

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

Performs copy-assignment from source.

impl Debug for Image

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

Formats the value using the given formatter.

impl Default for Image

fn default() -> Image

default is a 1x1x1 all ‘1.0’ texture

impl FromArg for &'static Image

where Image: Any + Send + Sync,

type This<'from_arg> = &'from_arg Image

The type to convert into.

fn from_arg( arg: Arg<'_>, ) -> Result<<&'static Image as FromArg>::This<'_>, ArgError>

Creates an item from an argument.

impl FromArg for &'static mut Image

where Image: Any + Send + Sync,

type This<'from_arg> = &'from_arg mut Image

The type to convert into.

fn from_arg( arg: Arg<'_>, ) -> Result<<&'static mut Image as FromArg>::This<'_>, ArgError>

Creates an item from an argument.

impl FromArg for Image

where Image: Any + Send + Sync,

type This<'from_arg> = Image

The type to convert into.

fn from_arg(arg: Arg<'_>) -> Result<<Image as FromArg>::This<'_>, ArgError>

Creates an item from an argument.

impl FromReflect for Image

where Image: Any + Send + Sync,

fn from_reflect(reflect: &(dyn PartialReflect + 'static)) -> Option<Image>

Constructs a concrete instance of Self from a reflected value.

fn take_from_reflect( reflect: Box<dyn PartialReflect>, ) -> Result<Self, Box<dyn PartialReflect>>

Attempts to downcast the given value to Self using, constructing the value using from_reflect if that fails.

impl GetOwnership for &Image

where Image: Any + Send + Sync,

fn ownership() -> Ownership

Returns the ownership of Self.

impl GetOwnership for &mut Image

where Image: Any + Send + Sync,

fn ownership() -> Ownership

Returns the ownership of Self.

impl GetOwnership for Image

where Image: Any + Send + Sync,

fn ownership() -> Ownership

Returns the ownership of Self.

impl GetTypeRegistration for Image

where Image: Any + Send + Sync,

fn get_type_registration() -> TypeRegistration

Returns the default TypeRegistration for this type.

fn register_type_dependencies(registry: &mut TypeRegistry)

Registers other types needed by this type.

impl IntoReturn for &Image

where Image: Any + Send + Sync,

fn into_return<'into_return>(self) -> Return<'into_return>

where &Image: 'into_return,

Converts Self into a Return value.

impl IntoReturn for &mut Image

where Image: Any + Send + Sync,

fn into_return<'into_return>(self) -> Return<'into_return>

where &mut Image: 'into_return,

Converts Self into a Return value.

impl IntoReturn for Image

where Image: Any + Send + Sync,

fn into_return<'into_return>(self) -> Return<'into_return>

where Image: 'into_return,

Converts Self into a Return value.

impl PartialReflect for Image

where Image: Any + Send + Sync,

fn get_represented_type_info(&self) -> Option<&'static TypeInfo>

Returns the TypeInfo of the type represented by this value.

fn clone_value(&self) -> Box<dyn PartialReflect>

Clones the value as a Reflect trait object.

fn try_apply( &mut self, value: &(dyn PartialReflect + 'static), ) -> Result<(), ApplyError>

Tries to apply a reflected value to this value.

fn reflect_kind(&self) -> ReflectKind

Returns a zero-sized enumeration of “kinds” of type.

fn reflect_ref(&self) -> ReflectRef<'_>

Returns an immutable enumeration of “kinds” of type.

fn reflect_mut(&mut self) -> ReflectMut<'_>

Returns a mutable enumeration of “kinds” of type.

fn reflect_owned(self: Box<Image>) -> ReflectOwned

Returns an owned enumeration of “kinds” of type.

fn try_into_reflect( self: Box<Image>, ) -> Result<Box<dyn Reflect>, Box<dyn PartialReflect>>

Attempts to cast this type to a boxed, fully-reflected value.

fn try_as_reflect(&self) -> Option<&(dyn Reflect + 'static)>

Attempts to cast this type to a fully-reflected value.

fn try_as_reflect_mut(&mut self) -> Option<&mut (dyn Reflect + 'static)>

Attempts to cast this type to a mutable, fully-reflected value.

fn into_partial_reflect(self: Box<Image>) -> Box<dyn PartialReflect>

Casts this type to a boxed, reflected value.

fn as_partial_reflect(&self) -> &(dyn PartialReflect + 'static)

Casts this type to a reflected value.

fn as_partial_reflect_mut(&mut self) -> &mut (dyn PartialReflect + 'static)

Casts this type to a mutable, reflected value.

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

Debug formatter for the value.

fn apply(&mut self, value: &(dyn PartialReflect + 'static))

Applies a reflected value to this value.

fn reflect_hash(&self) -> Option<u64>

Returns a hash of the value (which includes the type).

fn reflect_partial_eq( &self, _value: &(dyn PartialReflect + 'static), ) -> Option<bool>

Returns a “partial equality” comparison result.

fn serializable(&self) -> Option<Serializable<'_>>

Returns a serializable version of the value.

fn is_dynamic(&self) -> bool

Indicates whether or not this type is a dynamic type.

impl Reflect for Image

where Image: Any + Send + Sync,

fn into_any(self: Box<Image>) -> Box<dyn Any>

Returns the value as a Box<dyn Any>.

fn as_any(&self) -> &(dyn Any + 'static)

Returns the value as a &dyn Any.

fn as_any_mut(&mut self) -> &mut (dyn Any + 'static)

Returns the value as a &mut dyn Any.

fn into_reflect(self: Box<Image>) -> Box<dyn Reflect>

Casts this type to a boxed, fully-reflected value.

fn as_reflect(&self) -> &(dyn Reflect + 'static)

Casts this type to a fully-reflected value.

fn as_reflect_mut(&mut self) -> &mut (dyn Reflect + 'static)

Casts this type to a mutable, fully-reflected value.

fn set(&mut self, value: Box<dyn Reflect>) -> Result<(), Box<dyn Reflect>>

Performs a type-checked assignment of a reflected value to this value.

impl TypePath for Image

where Image: Any + Send + Sync,

fn type_path() -> &'static str

Returns the fully qualified path of the underlying type.

fn short_type_path() -> &'static str

Returns a short, pretty-print enabled path to the type.

fn type_ident() -> Option<&'static str>

Returns the name of the type, or None if it is anonymous.

fn crate_name() -> Option<&'static str>

Returns the name of the crate the type is in, or None if it is anonymous.

fn module_path() -> Option<&'static str>

Returns the path to the module the type is in, or None if it is anonymous.

impl Typed for Image

where Image: Any + Send + Sync,

fn type_info() -> &'static TypeInfo

Returns the compile-time info for the underlying type.

impl VisitAssetDependencies for Image

fn visit_dependencies(&self, visit: &mut impl FnMut(UntypedAssetId))

impl Asset for Image