servo/components/script/dom/imagebitmap.rs
Bhuwan Pandit d7269c0f3b
refact: move create_image_bitmap to ImageBitmap Impl (#37348) (#37602)
This PR moves the `create_image_bitmap` method from `GlobalScope` to a
helper function within the `ImageBitmap` implementation in
`imagebitmap.rs`.

Moving this method improves code organization and maintainability. Given
that `globalscope.rs` is already quite large, relocating
`create_image_bitmap` to `imagebitmap.rs` places it closer to the
`ImageBitmap` struct it primarily operates on.

As mentioned in the issue description (No dedicated tests are required
for this change, as long as the project builds), which it does using
`./mach build`. Also ran `./mach fmt` and `./mach test-tidy` which both
didn't report any issue.

Closes #37348

Signed-off-by: Bhuwan Pandit <bhuwanpandit109@gmail.com>
2025-06-21 04:12:11 +00:00

793 lines
32 KiB
Rust

/* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this
* file, You can obtain one at https://mozilla.org/MPL/2.0/. */
use std::cell::{Cell, Ref};
use std::collections::HashMap;
use std::rc::Rc;
use base::id::{ImageBitmapId, ImageBitmapIndex};
use constellation_traits::SerializableImageBitmap;
use dom_struct::dom_struct;
use euclid::default::{Point2D, Rect, Size2D};
use pixels::{CorsStatus, PixelFormat, Snapshot, SnapshotAlphaMode, SnapshotPixelFormat};
use script_bindings::error::Error;
use script_bindings::realms::{AlreadyInRealm, InRealm};
use crate::dom::bindings::cell::DomRefCell;
use crate::dom::bindings::codegen::Bindings::ImageBitmapBinding::{
ImageBitmapMethods, ImageBitmapOptions, ImageBitmapSource, ImageOrientation, PremultiplyAlpha,
ResizeQuality,
};
use crate::dom::bindings::refcounted::Trusted;
use crate::dom::bindings::reflector::{Reflector, reflect_dom_object};
use crate::dom::bindings::root::DomRoot;
use crate::dom::bindings::serializable::Serializable;
use crate::dom::bindings::structuredclone::StructuredData;
use crate::dom::bindings::transferable::Transferable;
use crate::dom::globalscope::GlobalScope;
use crate::dom::types::Promise;
use crate::script_runtime::CanGc;
use crate::test::TrustedPromise;
#[dom_struct]
pub(crate) struct ImageBitmap {
reflector_: Reflector,
/// The actual pixel data of the bitmap
///
/// If this is `None`, then the bitmap data has been released by calling
/// [`close`](https://html.spec.whatwg.org/multipage/#dom-imagebitmap-close)
#[no_trace]
bitmap_data: DomRefCell<Option<Snapshot>>,
origin_clean: Cell<bool>,
}
impl ImageBitmap {
fn new_inherited(bitmap_data: Snapshot) -> ImageBitmap {
ImageBitmap {
reflector_: Reflector::new(),
bitmap_data: DomRefCell::new(Some(bitmap_data)),
origin_clean: Cell::new(true),
}
}
pub(crate) fn new(
global: &GlobalScope,
bitmap_data: Snapshot,
can_gc: CanGc,
) -> DomRoot<ImageBitmap> {
reflect_dom_object(
Box::new(ImageBitmap::new_inherited(bitmap_data)),
global,
can_gc,
)
}
#[allow(dead_code)]
pub(crate) fn bitmap_data(&self) -> Ref<Option<Snapshot>> {
self.bitmap_data.borrow()
}
pub(crate) fn origin_is_clean(&self) -> bool {
self.origin_clean.get()
}
pub(crate) fn set_origin_clean(&self, origin_is_clean: bool) {
self.origin_clean.set(origin_is_clean);
}
/// Return the value of the [`[[Detached]]`](https://html.spec.whatwg.org/multipage/#detached)
/// internal slot
pub(crate) fn is_detached(&self) -> bool {
self.bitmap_data.borrow().is_none()
}
/// <https://html.spec.whatwg.org/multipage/#cropped-to-the-source-rectangle-with-formatting>
pub(crate) fn crop_and_transform_bitmap_data(
input: Snapshot,
mut sx: i32,
mut sy: i32,
sw: Option<i32>,
sh: Option<i32>,
options: &ImageBitmapOptions,
) -> Option<Snapshot> {
let input_size = input.size().to_i32();
// Step 2. If sx, sy, sw and sh are specified, let sourceRectangle be a rectangle whose corners
// are the four points (sx, sy), (sx+sw, sy), (sx+sw, sy+sh), (sx, sy+sh). Otherwise,
// let sourceRectangle be a rectangle whose corners are the four points (0, 0), (width of input, 0),
// (width of input, height of input), (0, height of input). If either sw or sh are negative,
// then the top-left corner of this rectangle will be to the left or above the (sx, sy) point.
let sw = sw.map_or(input_size.width, |width| {
if width < 0 {
sx = sx.saturating_add(width);
width.saturating_abs()
} else {
width
}
});
let sh = sh.map_or(input_size.height, |height| {
if height < 0 {
sy = sy.saturating_add(height);
height.saturating_abs()
} else {
height
}
});
let source_rect = Rect::new(Point2D::new(sx, sy), Size2D::new(sw, sh));
// Whether the byte length of the source bitmap exceeds the supported range.
// In the case the source is too large, we should fail, and that is not defined.
// <https://github.com/whatwg/html/issues/3323>
let Some(source_byte_length) = pixels::compute_rgba8_byte_length_if_within_limit(
source_rect.size.width as usize,
source_rect.size.height as usize,
) else {
log::warn!(
"Failed to allocate bitmap of size {:?}, too large",
source_rect.size
);
return None;
};
// Step 3. Let outputWidth be determined as follows:
// Step 4. Let outputHeight be determined as follows:
let output_size = match (options.resizeWidth, options.resizeHeight) {
(Some(width), Some(height)) => Size2D::new(width, height),
(Some(width), None) => {
let height =
source_rect.size.height as f64 * width as f64 / source_rect.size.width as f64;
Size2D::new(width, height.round() as u32)
},
(None, Some(height)) => {
let width =
source_rect.size.width as f64 * height as f64 / source_rect.size.height as f64;
Size2D::new(width.round() as u32, height)
},
(None, None) => source_rect.size.to_u32(),
};
// Whether the byte length of the output bitmap exceeds the supported range.
// In the case the output is too large, we should fail, and that is not defined.
// <https://github.com/whatwg/html/issues/3323>
let Some(output_byte_length) = pixels::compute_rgba8_byte_length_if_within_limit(
output_size.width as usize,
output_size.height as usize,
) else {
log::warn!(
"Failed to allocate bitmap of size {:?}, too large",
output_size
);
return None;
};
// TODO: Take into account the image orientation (such as EXIF metadata).
// Step 5. Place input on an infinite transparent black grid plane, positioned so that
// its top left corner is at the origin of the plane, with the x-coordinate increasing to the right,
// and the y-coordinate increasing down, and with each pixel in the input image data occupying a cell
// on the plane's grid.
let input_rect = Rect::new(Point2D::zero(), input_size);
let input_rect_cropped = source_rect
.intersection(&input_rect)
.unwrap_or(Rect::zero());
// Early out for empty tranformations.
if input_rect_cropped.is_empty() {
return Some(Snapshot::cleared(output_size));
}
// Step 6. Let output be the rectangle on the plane denoted by sourceRectangle.
let mut source: Snapshot = Snapshot::from_vec(
source_rect.size.cast(),
input.format(),
input.alpha_mode(),
vec![0; source_byte_length],
);
let source_rect_cropped = Rect::new(
Point2D::new(
input_rect_cropped.origin.x - source_rect.origin.x,
input_rect_cropped.origin.y - source_rect.origin.y,
),
input_rect_cropped.size,
);
pixels::copy_rgba8_image(
input.size(),
input_rect_cropped.cast(),
input.data(),
source.size(),
source_rect_cropped.cast(),
source.data_mut(),
);
// Step 7. Scale output to the size specified by outputWidth and outputHeight.
let mut output = if source.size() != output_size {
let quality = match options.resizeQuality {
ResizeQuality::Pixelated => pixels::FilterQuality::None,
ResizeQuality::Low => pixels::FilterQuality::Low,
ResizeQuality::Medium => pixels::FilterQuality::Medium,
ResizeQuality::High => pixels::FilterQuality::High,
};
let Some(output_data) =
pixels::scale_rgba8_image(source.size(), source.data(), output_size, quality)
else {
log::warn!(
"Failed to scale the bitmap of size {:?} to required size {:?}",
source.size(),
output_size
);
return None;
};
debug_assert_eq!(output_data.len(), output_byte_length);
Snapshot::from_vec(
output_size,
source.format(),
source.alpha_mode(),
output_data,
)
} else {
source
};
// Step 8. If the value of the imageOrientation member of options is "flipY",
// output must be flipped vertically, disregarding any image orientation metadata
// of the source (such as EXIF metadata), if any.
if options.imageOrientation == ImageOrientation::FlipY {
pixels::flip_y_rgba8_image_inplace(output.size(), output.data_mut());
}
// TODO: Step 9. If image is an img element or a Blob object, let val be the value
// of the colorSpaceConversion member of options, and then run these substeps:
// Step 10. Let val be the value of premultiplyAlpha member of options,
// and then run these substeps:
// TODO: Preserve the original input pixel format and perform conversion on demand.
match options.premultiplyAlpha {
PremultiplyAlpha::Default | PremultiplyAlpha::Premultiply => {
output.transform(
SnapshotAlphaMode::Transparent {
premultiplied: true,
},
SnapshotPixelFormat::BGRA,
);
},
PremultiplyAlpha::None => {
output.transform(
SnapshotAlphaMode::Transparent {
premultiplied: false,
},
SnapshotPixelFormat::BGRA,
);
},
}
// Step 11. Return output.
Some(output)
}
/// <https://html.spec.whatwg.org/multipage/#dom-createimagebitmap>
#[allow(clippy::too_many_arguments)]
pub(crate) fn create_image_bitmap(
global_scope: &GlobalScope,
image: ImageBitmapSource,
sx: i32,
sy: i32,
sw: Option<i32>,
sh: Option<i32>,
options: &ImageBitmapOptions,
can_gc: CanGc,
) -> Rc<Promise> {
let in_realm_proof = AlreadyInRealm::assert::<crate::DomTypeHolder>();
let p = Promise::new_in_current_realm(InRealm::Already(&in_realm_proof), can_gc);
// Step 1. If either sw or sh is given and is 0, then return a promise rejected with a RangeError.
if sw.is_some_and(|w| w == 0) {
p.reject_error(
Error::Range("'sw' must be a non-zero value".to_owned()),
can_gc,
);
return p;
}
if sh.is_some_and(|h| h == 0) {
p.reject_error(
Error::Range("'sh' must be a non-zero value".to_owned()),
can_gc,
);
return p;
}
// Step 2. If either options's resizeWidth or options's resizeHeight is present and is 0,
// then return a promise rejected with an "InvalidStateError" DOMException.
if options.resizeWidth.is_some_and(|w| w == 0) {
p.reject_error(Error::InvalidState, can_gc);
return p;
}
if options.resizeHeight.is_some_and(|h| h == 0) {
p.reject_error(Error::InvalidState, can_gc);
return p;
}
// The promise with image bitmap should be fulfilled on the the bitmap task source.
let fullfill_promise_on_bitmap_task_source =
|promise: &Rc<Promise>, image_bitmap: &ImageBitmap| {
let trusted_promise = TrustedPromise::new(promise.clone());
let trusted_image_bitmap = Trusted::new(image_bitmap);
global_scope.task_manager().bitmap_task_source().queue(
task!(resolve_promise: move || {
let promise = trusted_promise.root();
let image_bitmap = trusted_image_bitmap.root();
promise.resolve_native(&image_bitmap, CanGc::note());
}),
);
};
// The promise with "InvalidStateError" DOMException should be rejected
// on the the bitmap task source.
let reject_promise_on_bitmap_task_source = |promise: &Rc<Promise>| {
let trusted_promise = TrustedPromise::new(promise.clone());
global_scope
.task_manager()
.bitmap_task_source()
.queue(task!(reject_promise: move || {
let promise = trusted_promise.root();
promise.reject_error(Error::InvalidState, CanGc::note());
}));
};
// Step 3. Check the usability of the image argument. If this throws an exception or returns bad,
// then return a promise rejected with an "InvalidStateError" DOMException.
// Step 6. Switch on image:
match image {
ImageBitmapSource::HTMLImageElement(ref image) => {
// <https://html.spec.whatwg.org/multipage/#check-the-usability-of-the-image-argument>
if !image.is_usable().is_ok_and(|u| u) {
p.reject_error(Error::InvalidState, can_gc);
return p;
}
// If no ImageBitmap object can be constructed, then the promise is rejected instead.
let Some(img) = image.image_data() else {
p.reject_error(Error::InvalidState, can_gc);
return p;
};
// TODO: Support vector HTMLImageElement.
let Some(img) = img.as_raster_image() else {
p.reject_error(Error::InvalidState, can_gc);
return p;
};
let size = Size2D::new(img.metadata.width, img.metadata.height);
let format = match img.format {
PixelFormat::BGRA8 => SnapshotPixelFormat::BGRA,
PixelFormat::RGBA8 => SnapshotPixelFormat::RGBA,
pixel_format => {
unimplemented!("unsupported pixel format ({:?})", pixel_format)
},
};
let alpha_mode = SnapshotAlphaMode::Transparent {
premultiplied: false,
};
let snapshot = Snapshot::from_vec(
size.cast(),
format,
alpha_mode,
img.first_frame().bytes.to_vec(),
);
// Step 6.3. Set imageBitmap's bitmap data to a copy of image's media data,
// cropped to the source rectangle with formatting.
let Some(bitmap_data) =
ImageBitmap::crop_and_transform_bitmap_data(snapshot, sx, sy, sw, sh, options)
else {
p.reject_error(Error::InvalidState, can_gc);
return p;
};
let image_bitmap = Self::new(global_scope, bitmap_data, can_gc);
// Step 6.4. If image is not origin-clean, then set the origin-clean flag
// of imageBitmap's bitmap to false.
image_bitmap.set_origin_clean(image.same_origin(GlobalScope::entry().origin()));
// Step 6.5. Queue a global task, using the bitmap task source,
// to resolve promise with imageBitmap.
fullfill_promise_on_bitmap_task_source(&p, &image_bitmap);
},
ImageBitmapSource::HTMLVideoElement(ref video) => {
// <https://html.spec.whatwg.org/multipage/#check-the-usability-of-the-image-argument>
if !video.is_usable() {
p.reject_error(Error::InvalidState, can_gc);
return p;
}
// Step 6.1. If image's networkState attribute is NETWORK_EMPTY, then return
// a promise rejected with an "InvalidStateError" DOMException.
if video.is_network_state_empty() {
p.reject_error(Error::InvalidState, can_gc);
return p;
}
// If no ImageBitmap object can be constructed, then the promise is rejected instead.
let Some(snapshot) = video.get_current_frame_data() else {
p.reject_error(Error::InvalidState, can_gc);
return p;
};
// Step 6.2. Set imageBitmap's bitmap data to a copy of the frame at the current
// playback position, at the media resource's natural width and natural height
// (i.e., after any aspect-ratio correction has been applied),
// cropped to the source rectangle with formatting.
let Some(bitmap_data) =
ImageBitmap::crop_and_transform_bitmap_data(snapshot, sx, sy, sw, sh, options)
else {
p.reject_error(Error::InvalidState, can_gc);
return p;
};
let image_bitmap = Self::new(global_scope, bitmap_data, can_gc);
// Step 6.3. If image is not origin-clean, then set the origin-clean flag
// of imageBitmap's bitmap to false.
image_bitmap.set_origin_clean(video.origin_is_clean());
// Step 6.4. Queue a global task, using the bitmap task source,
// to resolve promise with imageBitmap.
fullfill_promise_on_bitmap_task_source(&p, &image_bitmap);
},
ImageBitmapSource::HTMLCanvasElement(ref canvas) => {
// <https://html.spec.whatwg.org/multipage/#check-the-usability-of-the-image-argument>
if canvas.get_size().is_empty() {
p.reject_error(Error::InvalidState, can_gc);
return p;
}
// If no ImageBitmap object can be constructed, then the promise is rejected instead.
let Some(snapshot) = canvas.get_image_data() else {
p.reject_error(Error::InvalidState, can_gc);
return p;
};
// Step 6.1. Set imageBitmap's bitmap data to a copy of image's bitmap data,
// cropped to the source rectangle with formatting.
let Some(bitmap_data) =
ImageBitmap::crop_and_transform_bitmap_data(snapshot, sx, sy, sw, sh, options)
else {
p.reject_error(Error::InvalidState, can_gc);
return p;
};
let image_bitmap = Self::new(global_scope, bitmap_data, can_gc);
// Step 6.2. Set the origin-clean flag of the imageBitmap's bitmap to the same value
// as the origin-clean flag of image's bitmap.
image_bitmap.set_origin_clean(canvas.origin_is_clean());
// Step 6.3. Queue a global task, using the bitmap task source,
// to resolve promise with imageBitmap.
fullfill_promise_on_bitmap_task_source(&p, &image_bitmap);
},
ImageBitmapSource::ImageBitmap(ref bitmap) => {
// <https://html.spec.whatwg.org/multipage/#check-the-usability-of-the-image-argument>
if bitmap.is_detached() {
p.reject_error(Error::InvalidState, can_gc);
return p;
}
// If no ImageBitmap object can be constructed, then the promise is rejected instead.
let Some(snapshot) = bitmap.bitmap_data().clone() else {
p.reject_error(Error::InvalidState, can_gc);
return p;
};
// Step 6.1. Set imageBitmap's bitmap data to a copy of image's bitmap data,
// cropped to the source rectangle with formatting.
let Some(bitmap_data) =
ImageBitmap::crop_and_transform_bitmap_data(snapshot, sx, sy, sw, sh, options)
else {
p.reject_error(Error::InvalidState, can_gc);
return p;
};
let image_bitmap = Self::new(global_scope, bitmap_data, can_gc);
// Step 6.2. Set the origin-clean flag of imageBitmap's bitmap to the same value
// as the origin-clean flag of image's bitmap.
image_bitmap.set_origin_clean(bitmap.origin_is_clean());
// Step 6.3. Queue a global task, using the bitmap task source,
// to resolve promise with imageBitmap.
fullfill_promise_on_bitmap_task_source(&p, &image_bitmap);
},
ImageBitmapSource::OffscreenCanvas(ref canvas) => {
// <https://html.spec.whatwg.org/multipage/#check-the-usability-of-the-image-argument>
if canvas.get_size().is_empty() {
p.reject_error(Error::InvalidState, can_gc);
return p;
}
// If no ImageBitmap object can be constructed, then the promise is rejected instead.
let Some(snapshot) = canvas.get_image_data() else {
p.reject_error(Error::InvalidState, can_gc);
return p;
};
// Step 6.1. Set imageBitmap's bitmap data to a copy of image's bitmap data,
// cropped to the source rectangle with formatting.
let Some(bitmap_data) =
ImageBitmap::crop_and_transform_bitmap_data(snapshot, sx, sy, sw, sh, options)
else {
p.reject_error(Error::InvalidState, can_gc);
return p;
};
let image_bitmap = Self::new(global_scope, bitmap_data, can_gc);
// Step 6.2. Set the origin-clean flag of the imageBitmap's bitmap to the same value
// as the origin-clean flag of image's bitmap.
image_bitmap.set_origin_clean(canvas.origin_is_clean());
// Step 6.3. Queue a global task, using the bitmap task source,
// to resolve promise with imageBitmap.
fullfill_promise_on_bitmap_task_source(&p, &image_bitmap);
},
ImageBitmapSource::Blob(ref blob) => {
// Step 6.1. Let imageData be the result of reading image's data.
// If an error occurs during reading of the object, then queue
// a global task, using the bitmap task source, to reject promise
// with an "InvalidStateError" DOMException and abort these steps.
let Ok(bytes) = blob.get_bytes() else {
reject_promise_on_bitmap_task_source(&p);
return p;
};
// Step 6.2. Apply the image sniffing rules to determine the file
// format of imageData, with MIME type of image (as given by
// image's type attribute) giving the official type.
// Step 6.3. If imageData is not in a supported image file format
// (e.g., it's not an image at all), or if imageData is corrupted
// in some fatal way such that the image dimensions cannot be obtained
// (e.g., a vector graphic with no natural size), then queue
// a global task, using the bitmap task source, to reject promise
// with an "InvalidStateError" DOMException and abort these steps.
let Some(img) = pixels::load_from_memory(&bytes, CorsStatus::Safe) else {
reject_promise_on_bitmap_task_source(&p);
return p;
};
let size = Size2D::new(img.metadata.width, img.metadata.height);
let format = match img.format {
PixelFormat::BGRA8 => SnapshotPixelFormat::BGRA,
PixelFormat::RGBA8 => SnapshotPixelFormat::RGBA,
pixel_format => {
unimplemented!("unsupported pixel format ({:?})", pixel_format)
},
};
let alpha_mode = SnapshotAlphaMode::Transparent {
premultiplied: false,
};
let snapshot = Snapshot::from_vec(
size.cast(),
format,
alpha_mode,
img.first_frame().bytes.to_vec(),
);
// Step 6.4. Set imageBitmap's bitmap data to imageData, cropped
// to the source rectangle with formatting.
let Some(bitmap_data) =
ImageBitmap::crop_and_transform_bitmap_data(snapshot, sx, sy, sw, sh, options)
else {
reject_promise_on_bitmap_task_source(&p);
return p;
};
let image_bitmap = Self::new(global_scope, bitmap_data, can_gc);
// Step 6.5. Queue a global task, using the bitmap task source,
// to resolve promise with imageBitmap.
fullfill_promise_on_bitmap_task_source(&p, &image_bitmap);
},
ImageBitmapSource::ImageData(ref image_data) => {
// Step 6.1. Let buffer be image's data attribute value's [[ViewedArrayBuffer]] internal slot.
// Step 6.2. If IsDetachedBuffer(buffer) is true, then return a promise rejected
// with an "InvalidStateError" DOMException.
if image_data.is_detached() {
p.reject_error(Error::InvalidState, can_gc);
return p;
}
let alpha_mode = SnapshotAlphaMode::Transparent {
premultiplied: false,
};
let snapshot = Snapshot::from_vec(
image_data.get_size().cast(),
SnapshotPixelFormat::RGBA,
alpha_mode,
image_data.to_vec(),
);
// Step 6.3. Set imageBitmap's bitmap data to image's image data,
// cropped to the source rectangle with formatting.
let Some(bitmap_data) =
ImageBitmap::crop_and_transform_bitmap_data(snapshot, sx, sy, sw, sh, options)
else {
p.reject_error(Error::InvalidState, can_gc);
return p;
};
let image_bitmap = Self::new(global_scope, bitmap_data, can_gc);
// Step 6.4. Queue a global task, using the bitmap task source,
// to resolve promise with imageBitmap.
fullfill_promise_on_bitmap_task_source(&p, &image_bitmap);
},
ImageBitmapSource::CSSStyleValue(_) => {
// TODO: CSSStyleValue is not part of ImageBitmapSource
// <https://html.spec.whatwg.org/multipage/#imagebitmapsource>
p.reject_error(Error::NotSupported, can_gc);
},
}
// Step 7. Return promise.
p
}
}
impl Serializable for ImageBitmap {
type Index = ImageBitmapIndex;
type Data = SerializableImageBitmap;
/// <https://html.spec.whatwg.org/multipage/#the-imagebitmap-interface:serialization-steps>
fn serialize(&self) -> Result<(ImageBitmapId, Self::Data), ()> {
// Step 1. If value's origin-clean flag is not set, then throw a "DataCloneError" DOMException.
if !self.origin_is_clean() {
return Err(());
}
// If value has a [[Detached]] internal slot whose value is true,
// then throw a "DataCloneError" DOMException.
if self.is_detached() {
return Err(());
}
// Step 2. Set serialized.[[BitmapData]] to a copy of value's bitmap data.
let serialized = SerializableImageBitmap {
bitmap_data: self.bitmap_data.borrow().clone().unwrap(),
};
Ok((ImageBitmapId::new(), serialized))
}
/// <https://html.spec.whatwg.org/multipage/#the-imagebitmap-interface:deserialization-steps>
fn deserialize(
owner: &GlobalScope,
serialized: Self::Data,
can_gc: CanGc,
) -> Result<DomRoot<Self>, ()> {
// Step 1. Set value's bitmap data to serialized.[[BitmapData]].
Ok(ImageBitmap::new(owner, serialized.bitmap_data, can_gc))
}
fn serialized_storage<'a>(
data: StructuredData<'a, '_>,
) -> &'a mut Option<HashMap<ImageBitmapId, Self::Data>> {
match data {
StructuredData::Reader(r) => &mut r.image_bitmaps,
StructuredData::Writer(w) => &mut w.image_bitmaps,
}
}
}
impl Transferable for ImageBitmap {
type Index = ImageBitmapIndex;
type Data = SerializableImageBitmap;
fn can_transfer(&self) -> bool {
if !self.origin_is_clean() || self.is_detached() {
return false;
}
true
}
/// <https://html.spec.whatwg.org/multipage/#the-imagebitmap-interface:transfer-steps>
fn transfer(&self) -> Result<(ImageBitmapId, SerializableImageBitmap), ()> {
// Step 1. If value's origin-clean flag is not set, then throw a "DataCloneError" DOMException.
if !self.origin_is_clean() {
return Err(());
}
// If value has a [[Detached]] internal slot whose value is true,
// then throw a "DataCloneError" DOMException.
if self.is_detached() {
return Err(());
}
// Step 2. Set dataHolder.[[BitmapData]] to value's bitmap data.
// Step 3. Unset value's bitmap data.
let serialized = SerializableImageBitmap {
bitmap_data: self.bitmap_data.borrow_mut().take().unwrap(),
};
Ok((ImageBitmapId::new(), serialized))
}
/// <https://html.spec.whatwg.org/multipage/#the-imagebitmap-interface:transfer-receiving-steps>
fn transfer_receive(
owner: &GlobalScope,
_: ImageBitmapId,
serialized: SerializableImageBitmap,
) -> Result<DomRoot<Self>, ()> {
// Step 1. Set value's bitmap data to serialized.[[BitmapData]].
Ok(ImageBitmap::new(
owner,
serialized.bitmap_data,
CanGc::note(),
))
}
fn serialized_storage<'a>(
data: StructuredData<'a, '_>,
) -> &'a mut Option<HashMap<ImageBitmapId, Self::Data>> {
match data {
StructuredData::Reader(r) => &mut r.transferred_image_bitmaps,
StructuredData::Writer(w) => &mut w.transferred_image_bitmaps,
}
}
}
impl ImageBitmapMethods<crate::DomTypeHolder> for ImageBitmap {
/// <https://html.spec.whatwg.org/multipage/#dom-imagebitmap-height>
fn Height(&self) -> u32 {
// Step 1. If this's [[Detached]] internal slot's value is true, then return 0.
if self.is_detached() {
return 0;
}
// Step 2. Return this's height, in CSS pixels.
self.bitmap_data
.borrow()
.as_ref()
.unwrap()
.size()
.cast()
.height
}
/// <https://html.spec.whatwg.org/multipage/#dom-imagebitmap-width>
fn Width(&self) -> u32 {
// Step 1. If this's [[Detached]] internal slot's value is true, then return 0.
if self.is_detached() {
return 0;
}
// Step 2. Return this's width, in CSS pixels.
self.bitmap_data
.borrow()
.as_ref()
.unwrap()
.size()
.cast()
.width
}
/// <https://html.spec.whatwg.org/multipage/#dom-imagebitmap-close>
fn Close(&self) {
// Step 1. Set this's [[Detached]] internal slot value to true.
// Step 2. Unset this's bitmap data.
// NOTE: The existence of the bitmap data is the internal slot in our implementation
self.bitmap_data.borrow_mut().take();
}
}