slint/internal/core/graphics/image.rs
2023-06-16 10:55:08 +02:00

833 lines
31 KiB
Rust

// Copyright © SixtyFPS GmbH <info@slint.dev>
// SPDX-License-Identifier: GPL-3.0-only OR LicenseRef-Slint-Royalty-free-1.0 OR LicenseRef-Slint-commercial
/*!
This module contains image decoding and caching related types for the run-time library.
*/
use crate::lengths::PhysicalPx;
use crate::slice::Slice;
use crate::{SharedString, SharedVector};
use super::{IntRect, IntSize};
use crate::items::ImageFit;
#[cfg(feature = "image-decoders")]
pub mod cache;
#[cfg(target_arch = "wasm32")]
mod htmlimage;
#[cfg(feature = "svg")]
mod svg;
#[allow(missing_docs)]
#[vtable::vtable]
#[repr(C)]
pub struct OpaqueImageVTable {
drop_in_place: fn(VRefMut<OpaqueImageVTable>) -> Layout,
dealloc: fn(&OpaqueImageVTable, ptr: *mut u8, layout: Layout),
/// Returns the image size
size: fn(VRef<OpaqueImageVTable>) -> IntSize,
/// Returns a cache key
cache_key: fn(VRef<OpaqueImageVTable>) -> ImageCacheKey,
}
#[cfg(feature = "svg")]
OpaqueImageVTable_static! {
/// VTable for RC wrapped SVG helper struct.
pub static PARSED_SVG_VT for svg::ParsedSVG
}
#[cfg(target_arch = "wasm32")]
OpaqueImageVTable_static! {
/// VTable for RC wrapped HtmlImage helper struct.
pub static HTML_IMAGE_VT for htmlimage::HTMLImage
}
/// SharedPixelBuffer is a container for storing image data as pixels. It is
/// internally reference counted and cheap to clone.
///
/// You can construct a new empty shared pixel buffer with [`SharedPixelBuffer::new`],
/// or you can clone it from an existing contiguous buffer that you might already have, using
/// [`SharedPixelBuffer::clone_from_slice`].
///
/// See the documentation for [`Image`] for examples how to use this type to integrate
/// Slint with external rendering functions.
#[derive(Debug, Clone)]
#[repr(C)]
pub struct SharedPixelBuffer<Pixel> {
width: u32,
height: u32,
data: SharedVector<Pixel>,
}
impl<Pixel> SharedPixelBuffer<Pixel> {
/// Returns the width of the image in pixels.
pub fn width(&self) -> u32 {
self.width
}
/// Returns the height of the image in pixels.
pub fn height(&self) -> u32 {
self.height
}
/// Returns the size of the image in pixels.
pub fn size(&self) -> IntSize {
[self.width, self.height].into()
}
}
impl<Pixel: Clone> SharedPixelBuffer<Pixel> {
/// Return a mutable slice to the pixel data. If the SharedPixelBuffer was shared, this will make a copy of the buffer.
pub fn make_mut_slice(&mut self) -> &mut [Pixel] {
self.data.make_mut_slice()
}
}
impl<Pixel: Clone + rgb::Pod> SharedPixelBuffer<Pixel>
where
[Pixel]: rgb::ComponentBytes<u8>,
{
/// Returns the pixels interpreted as raw bytes.
pub fn as_bytes(&self) -> &[u8] {
use rgb::ComponentBytes;
self.data.as_slice().as_bytes()
}
/// Returns the pixels interpreted as raw bytes.
pub fn make_mut_bytes(&mut self) -> &mut [u8] {
use rgb::ComponentBytes;
self.data.make_mut_slice().as_bytes_mut()
}
}
impl<Pixel> SharedPixelBuffer<Pixel> {
/// Return a slice to the pixel data.
pub fn as_slice(&self) -> &[Pixel] {
self.data.as_slice()
}
}
impl<Pixel: Clone + Default> SharedPixelBuffer<Pixel> {
/// Creates a new SharedPixelBuffer with the given width and height. Each pixel will be initialized with the value
/// that [`Default::default()`] returns for the Pixel type.
pub fn new(width: u32, height: u32) -> Self {
Self {
width,
height,
data: core::iter::repeat(Pixel::default())
.take(width as usize * height as usize)
.collect(),
}
}
}
impl<Pixel: Clone> SharedPixelBuffer<Pixel> {
/// Creates a new SharedPixelBuffer by cloning and converting pixels from an existing
/// slice. This function is useful when another crate was used to allocate an image
/// and you would like to convert it for use in Slint.
pub fn clone_from_slice<SourcePixelType>(
pixel_slice: &[SourcePixelType],
width: u32,
height: u32,
) -> Self
where
[SourcePixelType]: rgb::AsPixels<Pixel>,
{
use rgb::AsPixels;
Self { width, height, data: pixel_slice.as_pixels().iter().cloned().collect() }
}
}
/// Convenience alias for a pixel with three color channels (red, green and blue), each
/// encoded as u8.
pub type Rgb8Pixel = rgb::RGB8;
/// Convenience alias for a pixel with four color channels (red, green, blue and alpha), each
/// encoded as u8.
pub type Rgba8Pixel = rgb::RGBA8;
/// SharedImageBuffer is a container for images that are stored in CPU accessible memory.
///
/// The SharedImageBuffer's variants represent the different common formats for encoding
/// images in pixels.
#[derive(Clone, Debug)]
#[repr(C)]
pub enum SharedImageBuffer {
/// This variant holds the data for an image where each pixel has three color channels (red, green,
/// and blue) and each channel is encoded as unsigned byte.
RGB8(SharedPixelBuffer<Rgb8Pixel>),
/// This variant holds the data for an image where each pixel has four color channels (red, green,
/// blue and alpha) and each channel is encoded as unsigned byte.
RGBA8(SharedPixelBuffer<Rgba8Pixel>),
/// This variant holds the data for an image where each pixel has four color channels (red, green,
/// blue and alpha) and each channel is encoded as unsigned byte. In contrast to [`Self::RGBA8`],
/// this variant assumes that the alpha channel is also already multiplied to each red, green and blue
/// component of each pixel.
/// Only construct this format if you know that your pixels are encoded this way. It is more efficient
/// for rendering.
RGBA8Premultiplied(SharedPixelBuffer<Rgba8Pixel>),
}
impl SharedImageBuffer {
/// Returns the width of the image in pixels.
#[inline]
pub fn width(&self) -> u32 {
match self {
Self::RGB8(buffer) => buffer.width(),
Self::RGBA8(buffer) => buffer.width(),
Self::RGBA8Premultiplied(buffer) => buffer.width(),
}
}
/// Returns the height of the image in pixels.
#[inline]
pub fn height(&self) -> u32 {
match self {
Self::RGB8(buffer) => buffer.height(),
Self::RGBA8(buffer) => buffer.height(),
Self::RGBA8Premultiplied(buffer) => buffer.height(),
}
}
/// Returns the size of the image in pixels.
#[inline]
pub fn size(&self) -> IntSize {
match self {
Self::RGB8(buffer) => buffer.size(),
Self::RGBA8(buffer) => buffer.size(),
Self::RGBA8Premultiplied(buffer) => buffer.size(),
}
}
}
impl PartialEq for SharedImageBuffer {
fn eq(&self, other: &Self) -> bool {
match self {
Self::RGB8(lhs_buffer) => {
matches!(other, Self::RGB8(rhs_buffer) if lhs_buffer.data.as_ptr().eq(&rhs_buffer.data.as_ptr()))
}
Self::RGBA8(lhs_buffer) => {
matches!(other, Self::RGBA8(rhs_buffer) if lhs_buffer.data.as_ptr().eq(&rhs_buffer.data.as_ptr()))
}
Self::RGBA8Premultiplied(lhs_buffer) => {
matches!(other, Self::RGBA8Premultiplied(rhs_buffer) if lhs_buffer.data.as_ptr().eq(&rhs_buffer.data.as_ptr()))
}
}
}
}
#[repr(u8)]
#[derive(Clone, PartialEq, Debug, Copy)]
/// The pixel format of a StaticTexture
pub enum PixelFormat {
/// red, green, blue. 24bits.
Rgb,
/// Red, green, blue, alpha. 32bits.
Rgba,
/// Red, green, blue, alpha. 32bits. The color are premultiplied by alpha
RgbaPremultiplied,
/// Alpha map. 8bits. Each pixel is an alpha value. The color is specified separately.
AlphaMap,
}
impl PixelFormat {
/// The number of bytes in a pixel
pub fn bpp(self) -> usize {
match self {
PixelFormat::Rgb => 3,
PixelFormat::Rgba => 4,
PixelFormat::RgbaPremultiplied => 4,
PixelFormat::AlphaMap => 1,
}
}
}
#[repr(C)]
#[derive(Clone, PartialEq, Debug)]
/// Some raw pixel data which is typically stored in the binary
pub struct StaticTexture {
/// The position and size of the texture within the image
pub rect: IntRect,
/// The pixel format of this texture
pub format: PixelFormat,
/// The color, for the alpha map ones
pub color: crate::Color,
/// index in the data array
pub index: usize,
}
#[repr(C)]
#[derive(Clone, PartialEq, Debug)]
/// A texture is stored in read-only memory and may be composed of sub-textures.
pub struct StaticTextures {
/// The total size of the image (this might not be the size of the full image
/// as some transparent part are not part of any texture)
pub size: IntSize,
/// The size of the image before the compiler applied any scaling
pub original_size: IntSize,
/// The pixel data referenced by the textures
pub data: Slice<'static, u8>,
/// The list of textures
pub textures: Slice<'static, StaticTexture>,
}
/// ImageCacheKey encapsulates the different ways of indexing images in the
/// cache of decoded images.
#[derive(PartialEq, Eq, Debug, Hash, Clone)]
#[repr(u8)]
pub enum ImageCacheKey {
/// This variant indicates that no image cache key can be created for the image.
/// For example this is the case for programmatically created images.
Invalid = 0,
/// The image is identified by its path on the file system.
Path(SharedString) = 1,
/// The image is identified by a URL.
#[cfg(target_arch = "wasm32")]
URL(SharedString) = 2,
/// The image is identified by the static address of its encoded data.
EmbeddedData(usize) = 3,
}
impl ImageCacheKey {
/// Returns a new cache key if decoded image data can be stored in image cache for
/// the given ImageInner.
pub fn new(resource: &ImageInner) -> Option<Self> {
let key = match resource {
ImageInner::None => return None,
ImageInner::EmbeddedImage { cache_key, .. } => cache_key.clone(),
ImageInner::StaticTextures(textures) => {
Self::from_embedded_image_data(textures.data.as_slice())
}
#[cfg(feature = "svg")]
ImageInner::Svg(parsed_svg) => parsed_svg.cache_key(),
#[cfg(target_arch = "wasm32")]
ImageInner::HTMLImage(htmlimage) => Self::URL(htmlimage.source().into()),
ImageInner::BackendStorage(x) => vtable::VRc::borrow(x).cache_key(),
#[cfg(not(target_arch = "wasm32"))]
ImageInner::BorrowedOpenGLTexture(..) => return None,
};
if matches!(key, ImageCacheKey::Invalid) {
None
} else {
Some(key)
}
}
/// Returns a cache key for static embedded image data.
pub fn from_embedded_image_data(data: &'static [u8]) -> Self {
Self::EmbeddedData(data.as_ptr() as usize)
}
}
/// A resource is a reference to binary data, for example images. They can be accessible on the file
/// system or embedded in the resulting binary. Or they might be URLs to a web server and a downloaded
/// is necessary before they can be used.
/// cbindgen:prefix-with-name
#[derive(Clone, Debug, Default)]
#[repr(u8)]
#[allow(missing_docs)]
pub enum ImageInner {
/// A resource that does not represent any data.
#[default]
None,
EmbeddedImage {
cache_key: ImageCacheKey,
buffer: SharedImageBuffer,
},
#[cfg(feature = "svg")]
Svg(vtable::VRc<OpaqueImageVTable, svg::ParsedSVG>),
StaticTextures(&'static StaticTextures),
#[cfg(target_arch = "wasm32")]
HTMLImage(vtable::VRc<OpaqueImageVTable, htmlimage::HTMLImage>),
BackendStorage(vtable::VRc<OpaqueImageVTable>),
#[cfg(not(target_arch = "wasm32"))]
BorrowedOpenGLTexture(BorrowedOpenGLTexture),
}
impl ImageInner {
/// Return or render the image into a buffer
///
/// `target_size_for_scalable_source` is the size to use if the image is scalable.
///
/// Returns None if the image can't be rendered in a buffer
pub fn render_to_buffer(
&self,
_target_size_for_scalable_source: Option<euclid::Size2D<u32, PhysicalPx>>,
) -> Option<SharedImageBuffer> {
match self {
ImageInner::EmbeddedImage { buffer, .. } => Some(buffer.clone()),
#[cfg(feature = "svg")]
ImageInner::Svg(svg) => {
match svg.render(_target_size_for_scalable_source.unwrap_or_default()) {
Ok(b) => Some(b),
Err(err) => {
eprintln!("Error rendering SVG: {}", err);
return None;
}
}
}
ImageInner::StaticTextures(ts) => {
let mut buffer =
SharedPixelBuffer::<Rgba8Pixel>::new(ts.size.width, ts.size.height);
let stride = buffer.width() as usize;
let slice = buffer.make_mut_slice();
for t in ts.textures.iter() {
let rect = t.rect.to_usize();
for y in 0..rect.height() {
let slice = &mut slice[(rect.min_y() + y) * stride..][rect.x_range()];
let source = &ts.data[t.index + y * rect.width() * t.format.bpp()..];
match t.format {
PixelFormat::Rgb => {
let mut iter = source.chunks_exact(3).map(|p| Rgba8Pixel {
r: p[0],
g: p[1],
b: p[2],
a: 255,
});
slice.fill_with(|| iter.next().unwrap());
}
PixelFormat::RgbaPremultiplied => {
let mut iter = source.chunks_exact(4).map(|p| Rgba8Pixel {
r: p[0],
g: p[1],
b: p[2],
a: p[3],
});
slice.fill_with(|| iter.next().unwrap());
}
PixelFormat::Rgba => {
let mut iter = source.chunks_exact(4).map(|p| {
let a = p[3];
Rgba8Pixel {
r: (p[0] as u16 * a as u16 / 255) as u8,
g: (p[1] as u16 * a as u16 / 255) as u8,
b: (p[2] as u16 * a as u16 / 255) as u8,
a,
}
});
slice.fill_with(|| iter.next().unwrap());
}
PixelFormat::AlphaMap => {
let col = t.color.to_argb_u8();
let mut iter = source.iter().map(|p| {
let a = *p as u32 * col.alpha as u32;
Rgba8Pixel {
r: (col.red as u32 * a / (255 * 255)) as u8,
g: (col.green as u32 * a / (255 * 255)) as u8,
b: (col.blue as u32 * a / (255 * 255)) as u8,
a: (a / 255) as u8,
}
});
slice.fill_with(|| iter.next().unwrap());
}
};
}
}
Some(SharedImageBuffer::RGBA8Premultiplied(buffer))
}
_ => None,
}
}
/// Returns true if the image is an SVG (either backed by resvg or HTML image wrapper).
pub fn is_svg(&self) -> bool {
match self {
#[cfg(feature = "svg")]
Self::Svg(_) => true,
#[cfg(target_arch = "wasm32")]
Self::HTMLImage(html_image) => html_image.is_svg(),
_ => false,
}
}
}
impl PartialEq for ImageInner {
fn eq(&self, other: &Self) -> bool {
match (self, other) {
(
Self::EmbeddedImage { cache_key: l_cache_key, buffer: l_buffer },
Self::EmbeddedImage { cache_key: r_cache_key, buffer: r_buffer },
) => l_cache_key == r_cache_key && l_buffer == r_buffer,
#[cfg(feature = "svg")]
(Self::Svg(l0), Self::Svg(r0)) => vtable::VRc::ptr_eq(l0, r0),
(Self::StaticTextures(l0), Self::StaticTextures(r0)) => l0 == r0,
#[cfg(target_arch = "wasm32")]
(Self::HTMLImage(l0), Self::HTMLImage(r0)) => vtable::VRc::ptr_eq(l0, r0),
#[cfg(not(target_arch = "wasm32"))]
(Self::BorrowedOpenGLTexture(l0), Self::BorrowedOpenGLTexture(r0)) => l0 == r0,
_ => core::mem::discriminant(self) == core::mem::discriminant(other),
}
}
}
impl<'a> From<&'a Image> for &'a ImageInner {
fn from(other: &'a Image) -> Self {
&other.0
}
}
/// Error generated if an image cannot be loaded for any reasons.
#[derive(Default, Debug, PartialEq)]
pub struct LoadImageError(());
/// An image type that can be displayed by the Image element. You can construct
/// Image objects from a path to an image file on disk, using [`Self::load_from_path`].
///
/// Another typical use-case is to render the image content with Rust code.
/// For this it's most efficient to create a new SharedPixelBuffer with the known dimensions
/// and pass the mutable slice to your rendering function. Afterwards you can create an
/// Image.
///
/// The following example creates a 320x200 RGB pixel buffer and calls an external
/// low_level_render() function to draw a shape into it. Finally the result is
/// stored in an Image with [`Self::from_rgb8()`]:
/// ```
/// # use i_slint_core::graphics::{SharedPixelBuffer, Image, Rgb8Pixel};
///
/// fn low_level_render(width: u32, height: u32, buffer: &mut [u8]) {
/// // render beautiful circle or other shapes here
/// }
///
/// let mut pixel_buffer = SharedPixelBuffer::<Rgb8Pixel>::new(320, 200);
///
/// low_level_render(pixel_buffer.width(), pixel_buffer.height(),
/// pixel_buffer.make_mut_bytes());
///
/// let image = Image::from_rgb8(pixel_buffer);
/// ```
///
/// Another use-case is to import existing image data into Slint, by
/// creating a new Image through cloning of another image type.
///
/// The following example uses the popular [image crate](https://docs.rs/image/) to
/// load a `.png` file from disk, apply brightening filter on it and then import
/// it into an [`Image`]:
/// ```no_run
/// # use i_slint_core::graphics::{SharedPixelBuffer, Image, Rgba8Pixel};
/// let mut cat_image = image::open("cat.png").expect("Error loading cat image").into_rgba8();
///
/// image::imageops::colorops::brighten_in_place(&mut cat_image, 20);
///
/// let buffer = SharedPixelBuffer::<Rgba8Pixel>::clone_from_slice(
/// cat_image.as_raw(),
/// cat_image.width(),
/// cat_image.height(),
/// );
/// let image = Image::from_rgba8(buffer);
/// ```
///
/// A popular software (CPU) rendering library in Rust is tiny-skia. The following example shows
/// how to use tiny-skia to render into a [`SharedPixelBuffer`]:
/// ```
/// # use i_slint_core::graphics::{SharedPixelBuffer, Image, Rgba8Pixel};
/// let mut pixel_buffer = SharedPixelBuffer::<Rgba8Pixel>::new(640, 480);
/// let width = pixel_buffer.width();
/// let height = pixel_buffer.height();
/// let mut pixmap = tiny_skia::PixmapMut::from_bytes(
/// pixel_buffer.make_mut_bytes(), width, height
/// ).unwrap();
/// pixmap.fill(tiny_skia::Color::TRANSPARENT);
///
/// let circle = tiny_skia::PathBuilder::from_circle(320., 240., 150.).unwrap();
///
/// let mut paint = tiny_skia::Paint::default();
/// paint.shader = tiny_skia::LinearGradient::new(
/// tiny_skia::Point::from_xy(100.0, 100.0),
/// tiny_skia::Point::from_xy(400.0, 400.0),
/// vec![
/// tiny_skia::GradientStop::new(0.0, tiny_skia::Color::from_rgba8(50, 127, 150, 200)),
/// tiny_skia::GradientStop::new(1.0, tiny_skia::Color::from_rgba8(220, 140, 75, 180)),
/// ],
/// tiny_skia::SpreadMode::Pad,
/// tiny_skia::Transform::identity(),
/// ).unwrap();
///
/// pixmap.fill_path(&circle, &paint, tiny_skia::FillRule::Winding, Default::default(), None);
///
/// let image = Image::from_rgba8_premultiplied(pixel_buffer);
/// ```
///
/// ### Sending Image to a thread
///
/// `Image` is not [`Send`], because it uses internal cache that are local to the Slint thread.
/// If you want to create image data in a thread and send that to slint, construct the
/// [`SharedPixelBuffer`] in a thread, and send that to Slint's UI thread.
///
/// ```rust,no_run
/// # use i_slint_core::graphics::{SharedPixelBuffer, Image, Rgba8Pixel};
/// std::thread::spawn(move || {
/// let mut pixel_buffer = SharedPixelBuffer::<Rgba8Pixel>::new(640, 480);
/// // ... fill the pixel_buffer with data as shown in the previous example ...
/// slint::invoke_from_event_loop(move || {
/// // this will run in the Slint's UI thread
/// let image = Image::from_rgba8_premultiplied(pixel_buffer);
/// // ... use the image, eg:
/// // my_ui_handle.upgrade().unwrap().set_image(image);
/// });
/// });
/// ```
#[repr(transparent)]
#[derive(Default, Clone, Debug, PartialEq, derive_more::From)]
pub struct Image(ImageInner);
impl Image {
#[cfg(feature = "image-decoders")]
/// Load an Image from a path to a file containing an image
pub fn load_from_path(path: &std::path::Path) -> Result<Self, LoadImageError> {
self::cache::IMAGE_CACHE.with(|global_cache| {
let path: SharedString = path.to_str().ok_or(LoadImageError(()))?.into();
global_cache.borrow_mut().load_image_from_path(&path).ok_or(LoadImageError(()))
})
}
/// Creates a new Image from the specified shared pixel buffer, where each pixel has three color
/// channels (red, green and blue) encoded as u8.
pub fn from_rgb8(buffer: SharedPixelBuffer<Rgb8Pixel>) -> Self {
Image(ImageInner::EmbeddedImage {
cache_key: ImageCacheKey::Invalid,
buffer: SharedImageBuffer::RGB8(buffer),
})
}
/// Creates a new Image from the specified shared pixel buffer, where each pixel has four color
/// channels (red, green, blue and alpha) encoded as u8.
pub fn from_rgba8(buffer: SharedPixelBuffer<Rgba8Pixel>) -> Self {
Image(ImageInner::EmbeddedImage {
cache_key: ImageCacheKey::Invalid,
buffer: SharedImageBuffer::RGBA8(buffer),
})
}
/// Creates a new Image from the specified shared pixel buffer, where each pixel has four color
/// channels (red, green, blue and alpha) encoded as u8 and, in contrast to [`Self::from_rgba8`],
/// the alpha channel is also assumed to be multiplied to the red, green and blue channels.
///
/// Only construct an Image with this function if you know that your pixels are encoded this way.
pub fn from_rgba8_premultiplied(buffer: SharedPixelBuffer<Rgba8Pixel>) -> Self {
Image(ImageInner::EmbeddedImage {
cache_key: ImageCacheKey::Invalid,
buffer: SharedImageBuffer::RGBA8Premultiplied(buffer),
})
}
/// Creates a new Image from an existing OpenGL texture. The texture remains borrowed by Slint
/// for the duration of being used for rendering, such as when assigned as source property to
/// an `Image` element. It's the application's responsibility to delete the texture when it is
/// not used anymore.
///
/// The texture must be bindable against the `GL_TEXTURE_2D` target, have `GL_RGBA` as format
/// for the pixel data.
///
/// Safety: This method is marked as unsafe as passing invalid texture ids may result in
/// undefined behavior in OpenGL drivers.
#[allow(unsafe_code)]
#[cfg(not(target_arch = "wasm32"))]
pub unsafe fn from_borrowed_gl_2d_rgba_texture(
texture_id: core::num::NonZeroU32,
size: IntSize,
) -> Self {
Image(ImageInner::BorrowedOpenGLTexture(BorrowedOpenGLTexture { texture_id, size }))
}
/// Creates a new Image from the specified buffer, which contains SVG raw data.
#[cfg(feature = "svg")]
pub fn load_from_svg_data(buffer: &[u8]) -> Result<Self, LoadImageError> {
let cache_key = ImageCacheKey::Invalid;
Ok(Image(ImageInner::Svg(vtable::VRc::new(
svg::load_from_data(buffer, cache_key).map_err(|_| LoadImageError(()))?,
))))
}
/// Returns the size of the Image in pixels.
pub fn size(&self) -> IntSize {
match &self.0 {
ImageInner::None => Default::default(),
ImageInner::EmbeddedImage { buffer, .. } => buffer.size(),
ImageInner::StaticTextures(StaticTextures { original_size, .. }) => *original_size,
#[cfg(feature = "svg")]
ImageInner::Svg(svg) => svg.size(),
#[cfg(target_arch = "wasm32")]
ImageInner::HTMLImage(htmlimage) => htmlimage.size().unwrap_or_default(),
ImageInner::BackendStorage(x) => vtable::VRc::borrow(x).size(),
#[cfg(not(target_arch = "wasm32"))]
ImageInner::BorrowedOpenGLTexture(BorrowedOpenGLTexture { size, .. }) => *size,
}
}
#[cfg(feature = "std")]
/// Returns the path of the image on disk, if it was constructed via [`Self::load_from_path`].
///
/// For example:
/// ```
/// # use std::path::Path;
/// # use i_slint_core::graphics::*;
/// let path_buf = Path::new(env!("CARGO_MANIFEST_DIR"))
/// .join("../../examples/printerdemo/ui/images/cat.jpg");
/// let image = Image::load_from_path(&path_buf).unwrap();
/// assert_eq!(image.path(), Some(path_buf.as_path()));
/// ```
pub fn path(&self) -> Option<&std::path::Path> {
match &self.0 {
ImageInner::EmbeddedImage { cache_key, .. } => match cache_key {
ImageCacheKey::Path(path) => Some(std::path::Path::new(path.as_str())),
_ => None,
},
_ => None,
}
}
}
/// Load an image from an image embedded in the binary.
/// This is called by the generated code.
#[cfg(feature = "image-decoders")]
pub fn load_image_from_embedded_data(data: Slice<'static, u8>, format: Slice<'_, u8>) -> Image {
self::cache::IMAGE_CACHE.with(|global_cache| {
global_cache.borrow_mut().load_image_from_embedded_data(data, format).unwrap_or_else(|| {
panic!("internal error: embedded image data is not supported by run-time library",)
})
})
}
#[test]
fn test_image_size_from_buffer_without_backend() {
{
assert_eq!(Image::default().size(), Default::default());
}
{
let buffer = SharedPixelBuffer::<Rgb8Pixel>::new(320, 200);
let image = Image::from_rgb8(buffer);
assert_eq!(image.size(), [320, 200].into())
}
}
#[cfg(feature = "svg")]
#[test]
fn test_image_size_from_svg() {
let simple_svg = r#"<svg width="320" height="200" xmlns="http://www.w3.org/2000/svg"></svg>"#;
let image = Image::load_from_svg_data(simple_svg.as_bytes()).unwrap();
assert_eq!(image.size(), [320, 200].into());
}
#[cfg(feature = "svg")]
#[test]
fn test_image_invalid_svg() {
let invalid_svg = r#"AaBbCcDd"#;
let result = Image::load_from_svg_data(invalid_svg.as_bytes());
assert!(result.is_err());
}
/// Return an size that can be used to render an image in a buffer that matches a given ImageFit
pub fn fit_size(
image_fit: ImageFit,
target: euclid::Size2D<f32, PhysicalPx>,
origin: IntSize,
) -> euclid::Size2D<f32, PhysicalPx> {
let o = origin.cast::<f32>();
let ratio = match image_fit {
ImageFit::Fill => return target,
ImageFit::Contain => f32::min(target.width / o.width, target.height / o.height),
ImageFit::Cover => f32::max(target.width / o.width, target.height / o.height),
};
euclid::Size2D::from_untyped(o * ratio)
}
#[cfg(feature = "ffi")]
pub(crate) mod ffi {
#![allow(unsafe_code)]
use super::super::IntSize;
use super::*;
// Expand Rgb8Pixel so that cbindgen can see it. (is in fact rgb::RGB<u8>)
/// Represents an RGB pixel.
#[cfg(cbindgen)]
#[repr(C)]
struct Rgb8Pixel {
/// red value (between 0 and 255)
r: u8,
/// green value (between 0 and 255)
g: u8,
/// blue value (between 0 and 255)
b: u8,
}
// Expand Rgba8Pixel so that cbindgen can see it. (is in fact rgb::RGBA<u8>)
/// Represents an RGBA pixel.
#[cfg(cbindgen)]
#[repr(C)]
struct Rgba8Pixel {
/// red value (between 0 and 255)
r: u8,
/// green value (between 0 and 255)
g: u8,
/// blue value (between 0 and 255)
b: u8,
/// alpha value (between 0 and 255)
a: u8,
}
#[no_mangle]
pub unsafe extern "C" fn slint_image_load_from_path(path: &SharedString, image: *mut Image) {
std::ptr::write(
image,
Image::load_from_path(std::path::Path::new(path.as_str())).unwrap_or(Image::default()),
)
}
#[no_mangle]
pub unsafe extern "C" fn slint_image_load_from_embedded_data(
data: Slice<'static, u8>,
format: Slice<'static, u8>,
image: *mut Image,
) {
std::ptr::write(image, super::load_image_from_embedded_data(data, format));
}
#[no_mangle]
pub unsafe extern "C" fn slint_image_size(image: &Image) -> IntSize {
image.size()
}
#[no_mangle]
pub unsafe extern "C" fn slint_image_path(image: &Image) -> Option<&SharedString> {
match &image.0 {
ImageInner::EmbeddedImage { cache_key, .. } => match cache_key {
ImageCacheKey::Path(path) => Some(path),
_ => None,
},
_ => None,
}
}
#[no_mangle]
pub unsafe extern "C" fn slint_image_from_embedded_textures(
textures: &'static StaticTextures,
image: *mut Image,
) {
core::ptr::write(image, Image::from(ImageInner::StaticTextures(textures)));
}
#[no_mangle]
pub unsafe extern "C" fn slint_image_compare_equal(image1: &Image, image2: &Image) -> bool {
return image1.eq(image2);
}
}
/// This structure contains fields to identify and render an OpenGL texture that Slint borrows from the application code.
/// Use this to embed a native OpenGL texture into a Slint scene.
///
/// The ownership of the texture remains with the application. It is the application's responsibility to delete the texture
/// when it is not used anymore.
///
/// Note that only 2D RGBA textures are supported.
#[derive(Clone, Debug, PartialEq)]
#[non_exhaustive]
#[cfg(not(target_arch = "wasm32"))]
#[repr(C)]
pub struct BorrowedOpenGLTexture {
/// The id or name of the texture, as created by [`glGenTextures`](https://registry.khronos.org/OpenGL-Refpages/gl4/html/glGenTextures.xhtml).
pub texture_id: core::num::NonZeroU32,
/// The size of the texture in pixels.
pub size: IntSize,
}