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script/dom/canvas/
imagebitmap.rs

1/* This Source Code Form is subject to the terms of the Mozilla Public
2 * License, v. 2.0. If a copy of the MPL was not distributed with this
3 * file, You can obtain one at https://mozilla.org/MPL/2.0/. */
4
5use std::cell::{Cell, Ref};
6
7use dom_struct::dom_struct;
8use euclid::default::{Point2D, Rect, Size2D};
9use js::context::{JSContext, NoGC};
10use js::realm::CurrentRealm;
11use pixels::{CorsStatus, Snapshot, SnapshotAlphaMode, SnapshotPixelFormat};
12use rustc_hash::FxHashMap;
13use script_bindings::cell::DomRefCell;
14use script_bindings::error::{Error, Fallible};
15use script_bindings::reflector::{Reflector, reflect_dom_object};
16use servo_base::id::{ImageBitmapId, ImageBitmapIndex};
17use servo_constellation_traits::SerializableImageBitmap;
18
19use crate::dom::bindings::codegen::Bindings::ImageBitmapBinding::{
20    ImageBitmapMethods, ImageBitmapOptions, ImageBitmapSource, ImageOrientation, PremultiplyAlpha,
21    ResizeQuality,
22};
23use crate::dom::bindings::refcounted::{Trusted, TrustedPromise};
24use crate::dom::bindings::root::DomRoot;
25use crate::dom::bindings::serializable::Serializable;
26use crate::dom::bindings::structuredclone::StructuredData;
27use crate::dom::bindings::transferable::Transferable;
28use crate::dom::globalscope::GlobalScope;
29use crate::dom::promise::{Promise, RootedPromise};
30
31#[dom_struct]
32pub(crate) struct ImageBitmap {
33    reflector_: Reflector,
34    /// The actual pixel data of the bitmap
35    ///
36    /// If this is `None`, then the bitmap data has been released by calling
37    /// [`close`](https://html.spec.whatwg.org/multipage/#dom-imagebitmap-close)
38    #[no_trace]
39    bitmap_data: DomRefCell<Option<Snapshot>>,
40    origin_clean: Cell<bool>,
41}
42
43impl ImageBitmap {
44    fn new_inherited(bitmap_data: Snapshot) -> ImageBitmap {
45        ImageBitmap {
46            reflector_: Reflector::new(),
47            bitmap_data: DomRefCell::new(Some(bitmap_data)),
48            origin_clean: Cell::new(true),
49        }
50    }
51
52    pub(crate) fn new(
53        cx: &mut JSContext,
54        global: &GlobalScope,
55        bitmap_data: Snapshot,
56    ) -> DomRoot<ImageBitmap> {
57        reflect_dom_object(
58            cx,
59            Box::new(ImageBitmap::new_inherited(bitmap_data)),
60            global,
61        )
62    }
63
64    pub(crate) fn bitmap_data(&self) -> Ref<'_, Option<Snapshot>> {
65        self.bitmap_data.borrow()
66    }
67
68    pub(crate) fn origin_is_clean(&self) -> bool {
69        self.origin_clean.get()
70    }
71
72    pub(crate) fn set_origin_clean(&self, origin_is_clean: bool) {
73        self.origin_clean.set(origin_is_clean);
74    }
75
76    /// Return the value of the [`[[Detached]]`](https://html.spec.whatwg.org/multipage/#detached)
77    /// internal slot
78    pub(crate) fn is_detached(&self) -> bool {
79        self.bitmap_data.borrow().is_none()
80    }
81
82    /// <https://html.spec.whatwg.org/multipage/#cropped-to-the-source-rectangle-with-formatting>
83    pub(crate) fn crop_and_transform_bitmap_data(
84        input: Snapshot,
85        mut sx: i32,
86        mut sy: i32,
87        sw: Option<i32>,
88        sh: Option<i32>,
89        options: &ImageBitmapOptions,
90    ) -> Option<Snapshot> {
91        let input_size = input.size().to_i32();
92
93        // Step 2. If sx, sy, sw and sh are specified, let sourceRectangle be a rectangle whose corners
94        // are the four points (sx, sy), (sx+sw, sy), (sx+sw, sy+sh), (sx, sy+sh). Otherwise,
95        // let sourceRectangle be a rectangle whose corners are the four points (0, 0), (width of input, 0),
96        // (width of input, height of input), (0, height of input). If either sw or sh are negative,
97        // then the top-left corner of this rectangle will be to the left or above the (sx, sy) point.
98        let sw = sw.map_or(input_size.width, |width| {
99            if width < 0 {
100                sx = sx.saturating_add(width);
101                width.saturating_abs()
102            } else {
103                width
104            }
105        });
106
107        let sh = sh.map_or(input_size.height, |height| {
108            if height < 0 {
109                sy = sy.saturating_add(height);
110                height.saturating_abs()
111            } else {
112                height
113            }
114        });
115
116        let source_rect = Rect::new(Point2D::new(sx, sy), Size2D::new(sw, sh));
117
118        // Whether the byte length of the source bitmap exceeds the supported range.
119        // In the case the source is too large, we should fail, and that is not defined.
120        // <https://github.com/whatwg/html/issues/3323>
121        let Some(source_byte_length) = pixels::compute_rgba8_byte_length_if_within_limit(
122            source_rect.size.width as usize,
123            source_rect.size.height as usize,
124        ) else {
125            log::warn!(
126                "Failed to allocate bitmap of size {:?}, too large",
127                source_rect.size
128            );
129            return None;
130        };
131
132        // Step 3. Let outputWidth be determined as follows:
133        // Step 4. Let outputHeight be determined as follows:
134        let output_size = match (options.resizeWidth, options.resizeHeight) {
135            (Some(width), Some(height)) => Size2D::new(width, height),
136            (Some(width), None) => {
137                let height =
138                    source_rect.size.height as f64 * width as f64 / source_rect.size.width as f64;
139                Size2D::new(width, height.round() as u32)
140            },
141            (None, Some(height)) => {
142                let width =
143                    source_rect.size.width as f64 * height as f64 / source_rect.size.height as f64;
144                Size2D::new(width.round() as u32, height)
145            },
146            (None, None) => source_rect.size.to_u32(),
147        };
148
149        // Whether the byte length of the output bitmap exceeds the supported range.
150        // In the case the output is too large, we should fail, and that is not defined.
151        // <https://github.com/whatwg/html/issues/3323>
152        let Some(output_byte_length) = pixels::compute_rgba8_byte_length_if_within_limit(
153            output_size.width as usize,
154            output_size.height as usize,
155        ) else {
156            log::warn!(
157                "Failed to allocate bitmap of size {:?}, too large",
158                output_size
159            );
160            return None;
161        };
162
163        // TODO: Take into account the image orientation (such as EXIF metadata).
164
165        // Step 5. Place input on an infinite transparent black grid plane, positioned so that
166        // its top left corner is at the origin of the plane, with the x-coordinate increasing to the right,
167        // and the y-coordinate increasing down, and with each pixel in the input image data occupying a cell
168        // on the plane's grid.
169        let input_rect = Rect::new(Point2D::zero(), input_size);
170
171        let input_rect_cropped = source_rect
172            .intersection(&input_rect)
173            .unwrap_or(Rect::zero());
174
175        // Early out for empty tranformations.
176        if input_rect_cropped.is_empty() {
177            return Some(Snapshot::cleared(output_size));
178        }
179
180        // Step 6. Let output be the rectangle on the plane denoted by sourceRectangle.
181        let mut source: Snapshot = Snapshot::from_vec(
182            source_rect.size.cast(),
183            input.format(),
184            input.alpha_mode(),
185            vec![0; source_byte_length],
186        );
187
188        let source_rect_cropped = Rect::new(
189            Point2D::new(
190                input_rect_cropped.origin.x - source_rect.origin.x,
191                input_rect_cropped.origin.y - source_rect.origin.y,
192            ),
193            input_rect_cropped.size,
194        );
195
196        pixels::copy_rgba8_image(
197            input.size(),
198            input_rect_cropped.cast(),
199            input.as_raw_bytes(),
200            source.size(),
201            source_rect_cropped.cast(),
202            source.as_raw_bytes_mut(),
203        );
204
205        // Step 7. Scale output to the size specified by outputWidth and outputHeight.
206        let mut output = if source.size() != output_size {
207            let quality = match options.resizeQuality {
208                ResizeQuality::Pixelated => pixels::FilterQuality::None,
209                ResizeQuality::Low => pixels::FilterQuality::Low,
210                ResizeQuality::Medium => pixels::FilterQuality::Medium,
211                ResizeQuality::High => pixels::FilterQuality::High,
212            };
213
214            let Some(output_data) = pixels::scale_rgba8_image(
215                source.size(),
216                source.as_raw_bytes(),
217                output_size,
218                quality,
219            ) else {
220                log::warn!(
221                    "Failed to scale the bitmap of size {:?} to required size {:?}",
222                    source.size(),
223                    output_size
224                );
225                return None;
226            };
227
228            debug_assert_eq!(output_data.len(), output_byte_length);
229
230            Snapshot::from_vec(
231                output_size,
232                source.format(),
233                source.alpha_mode(),
234                output_data,
235            )
236        } else {
237            source
238        };
239
240        // Step 8. If the value of the imageOrientation member of options is "flipY",
241        // output must be flipped vertically, disregarding any image orientation metadata
242        // of the source (such as EXIF metadata), if any.
243        if options.imageOrientation == ImageOrientation::FlipY {
244            pixels::flip_y_rgba8_image_inplace(output.size(), output.as_raw_bytes_mut());
245        }
246
247        // TODO: Step 9. If image is an img element or a Blob object, let val be the value
248        // of the colorSpaceConversion member of options, and then run these substeps:
249
250        // Step 10. Let val be the value of premultiplyAlpha member of options,
251        // and then run these substeps:
252        // TODO: Preserve the original input pixel format and perform conversion on demand.
253        match options.premultiplyAlpha {
254            PremultiplyAlpha::Default | PremultiplyAlpha::Premultiply => {
255                output.transform(
256                    SnapshotAlphaMode::Transparent {
257                        premultiplied: true,
258                    },
259                    SnapshotPixelFormat::BGRA,
260                );
261            },
262            PremultiplyAlpha::None => {
263                output.transform(
264                    SnapshotAlphaMode::Transparent {
265                        premultiplied: false,
266                    },
267                    SnapshotPixelFormat::BGRA,
268                );
269            },
270        }
271
272        // Step 11. Return output.
273        Some(output)
274    }
275
276    /// <https://html.spec.whatwg.org/multipage/#dom-createimagebitmap>
277    #[allow(clippy::too_many_arguments)]
278    pub(crate) fn create_image_bitmap(
279        global_scope: &GlobalScope,
280        image: ImageBitmapSource,
281        sx: i32,
282        sy: i32,
283        sw: Option<i32>,
284        sh: Option<i32>,
285        options: &ImageBitmapOptions,
286        realm: &mut CurrentRealm,
287    ) -> RootedPromise {
288        let p = Promise::new_in_realm_rooted(realm);
289
290        // Step 1. If either sw or sh is given and is 0, then return a promise rejected with a RangeError.
291        if sw.is_some_and(|w| w == 0) {
292            p.reject_error(
293                realm,
294                Error::Range(c"'sw' must be a non-zero value".to_owned()),
295            );
296            return p;
297        }
298
299        if sh.is_some_and(|h| h == 0) {
300            p.reject_error(
301                realm,
302                Error::Range(c"'sh' must be a non-zero value".to_owned()),
303            );
304            return p;
305        }
306
307        // Step 2. If either options's resizeWidth or options's resizeHeight is present and is 0,
308        // then return a promise rejected with an "InvalidStateError" DOMException.
309        if options.resizeWidth.is_some_and(|w| w == 0) {
310            p.reject_error(realm, Error::InvalidState(None));
311            return p;
312        }
313
314        if options.resizeHeight.is_some_and(|h| h == 0) {
315            p.reject_error(realm, Error::InvalidState(None));
316            return p;
317        }
318
319        // The promise with image bitmap should be fulfilled on the bitmap task source.
320        let fullfill_promise_on_bitmap_task_source =
321            |promise: &RootedPromise, image_bitmap: &ImageBitmap| {
322                let trusted_promise = TrustedPromise::from(promise);
323                let trusted_image_bitmap = Trusted::new(image_bitmap);
324
325                global_scope.task_manager().bitmap_task_source().queue(
326                    task!(resolve_promise: move |cx| {
327                        let promise = trusted_promise.root(cx);
328                        let image_bitmap = trusted_image_bitmap.root();
329
330                        promise.resolve_native(cx, &image_bitmap);
331                    }),
332                );
333            };
334
335        // The promise with "InvalidStateError" DOMException should be rejected
336        // on the bitmap task source.
337        let reject_promise_on_bitmap_task_source = |promise: &RootedPromise| {
338            let trusted_promise = TrustedPromise::from(promise);
339
340            global_scope.task_manager().bitmap_task_source().queue(
341                task!(reject_promise: move |cx| {
342                    let promise = trusted_promise.root(cx);
343
344                    promise.reject_error(cx, Error::InvalidState(None));
345                }),
346            );
347        };
348
349        // Step 3. Check the usability of the image argument. If this throws an exception or returns bad,
350        // then return a promise rejected with an "InvalidStateError" DOMException.
351        // Step 6. Switch on image:
352        match image {
353            ImageBitmapSource::HTMLImageElement(ref image) => {
354                // <https://html.spec.whatwg.org/multipage/#check-the-usability-of-the-image-argument>
355                if !image.is_usable().is_ok_and(|u| u) {
356                    p.reject_error(realm, Error::InvalidState(None));
357                    return p;
358                }
359
360                // If no ImageBitmap object can be constructed, then the promise
361                // is rejected instead.
362                let Some(snapshot) = image.get_raster_image_data() else {
363                    p.reject_error(realm, Error::InvalidState(None));
364                    return p;
365                };
366
367                // Step 6.3. Set imageBitmap's bitmap data to a copy of image's media data,
368                // cropped to the source rectangle with formatting.
369                let Some(bitmap_data) =
370                    ImageBitmap::crop_and_transform_bitmap_data(snapshot, sx, sy, sw, sh, options)
371                else {
372                    p.reject_error(realm, Error::InvalidState(None));
373                    return p;
374                };
375
376                let image_bitmap = Self::new(realm, global_scope, bitmap_data);
377                // Step 6.4. If image is not origin-clean, then set the origin-clean flag
378                // of imageBitmap's bitmap to false.
379                image_bitmap.set_origin_clean(image.same_origin(&GlobalScope::entry().origin()));
380
381                // Step 6.5. Queue a global task, using the bitmap task source,
382                // to resolve promise with imageBitmap.
383                fullfill_promise_on_bitmap_task_source(&p, &image_bitmap);
384            },
385            ImageBitmapSource::HTMLVideoElement(ref video) => {
386                // <https://html.spec.whatwg.org/multipage/#check-the-usability-of-the-image-argument>
387                if !video.is_usable() {
388                    p.reject_error(realm, Error::InvalidState(None));
389                    return p;
390                }
391
392                // Step 6.1. If image's networkState attribute is NETWORK_EMPTY, then return
393                // a promise rejected with an "InvalidStateError" DOMException.
394                if video.is_network_state_empty() {
395                    p.reject_error(realm, Error::InvalidState(None));
396                    return p;
397                }
398
399                // If no ImageBitmap object can be constructed, then the promise is rejected instead.
400                let Some(snapshot) = video.get_current_frame_data() else {
401                    p.reject_error(realm, Error::InvalidState(None));
402                    return p;
403                };
404
405                // Step 6.2. Set imageBitmap's bitmap data to a copy of the frame at the current
406                // playback position, at the media resource's natural width and natural height
407                // (i.e., after any aspect-ratio correction has been applied),
408                // cropped to the source rectangle with formatting.
409                let Some(bitmap_data) =
410                    ImageBitmap::crop_and_transform_bitmap_data(snapshot, sx, sy, sw, sh, options)
411                else {
412                    p.reject_error(realm, Error::InvalidState(None));
413                    return p;
414                };
415
416                let image_bitmap = Self::new(realm, global_scope, bitmap_data);
417                // Step 6.3. If image is not origin-clean, then set the origin-clean flag
418                // of imageBitmap's bitmap to false.
419                image_bitmap.set_origin_clean(video.origin_is_clean());
420
421                // Step 6.4. Queue a global task, using the bitmap task source,
422                // to resolve promise with imageBitmap.
423                fullfill_promise_on_bitmap_task_source(&p, &image_bitmap);
424            },
425            ImageBitmapSource::HTMLCanvasElement(ref canvas) => {
426                // <https://html.spec.whatwg.org/multipage/#check-the-usability-of-the-image-argument>
427                if canvas.get_size().is_empty() {
428                    p.reject_error(realm, Error::InvalidState(None));
429                    return p;
430                }
431
432                // If no ImageBitmap object can be constructed, then the promise is rejected instead.
433                let Some(snapshot) = canvas.get_image_data() else {
434                    p.reject_error(realm, Error::InvalidState(None));
435                    return p;
436                };
437
438                // Step 6.1. Set imageBitmap's bitmap data to a copy of image's bitmap data,
439                // cropped to the source rectangle with formatting.
440                let Some(bitmap_data) =
441                    ImageBitmap::crop_and_transform_bitmap_data(snapshot, sx, sy, sw, sh, options)
442                else {
443                    p.reject_error(realm, Error::InvalidState(None));
444                    return p;
445                };
446
447                let image_bitmap = Self::new(realm, global_scope, bitmap_data);
448                // Step 6.2. Set the origin-clean flag of the imageBitmap's bitmap to the same value
449                // as the origin-clean flag of image's bitmap.
450                image_bitmap.set_origin_clean(canvas.origin_is_clean());
451
452                // Step 6.3. Queue a global task, using the bitmap task source,
453                // to resolve promise with imageBitmap.
454                fullfill_promise_on_bitmap_task_source(&p, &image_bitmap);
455            },
456            ImageBitmapSource::ImageBitmap(ref bitmap) => {
457                // <https://html.spec.whatwg.org/multipage/#check-the-usability-of-the-image-argument>
458                if bitmap.is_detached() {
459                    p.reject_error(realm, Error::InvalidState(None));
460                    return p;
461                }
462
463                // If no ImageBitmap object can be constructed, then the promise is rejected instead.
464                let Some(snapshot) = bitmap.bitmap_data().clone() else {
465                    p.reject_error(realm, Error::InvalidState(None));
466                    return p;
467                };
468
469                // Step 6.1. Set imageBitmap's bitmap data to a copy of image's bitmap data,
470                // cropped to the source rectangle with formatting.
471                let Some(bitmap_data) =
472                    ImageBitmap::crop_and_transform_bitmap_data(snapshot, sx, sy, sw, sh, options)
473                else {
474                    p.reject_error(realm, Error::InvalidState(None));
475                    return p;
476                };
477
478                let image_bitmap = Self::new(realm, global_scope, bitmap_data);
479                // Step 6.2. Set the origin-clean flag of imageBitmap's bitmap to the same value
480                // as the origin-clean flag of image's bitmap.
481                image_bitmap.set_origin_clean(bitmap.origin_is_clean());
482
483                // Step 6.3. Queue a global task, using the bitmap task source,
484                // to resolve promise with imageBitmap.
485                fullfill_promise_on_bitmap_task_source(&p, &image_bitmap);
486            },
487            ImageBitmapSource::OffscreenCanvas(ref canvas) => {
488                // <https://html.spec.whatwg.org/multipage/#check-the-usability-of-the-image-argument>
489                if canvas.get_size().is_empty() {
490                    p.reject_error(realm, Error::InvalidState(None));
491                    return p;
492                }
493
494                // If no ImageBitmap object can be constructed, then the promise is rejected instead.
495                let Some(snapshot) = canvas.get_image_data() else {
496                    p.reject_error(realm, Error::InvalidState(None));
497                    return p;
498                };
499
500                // Step 6.1. Set imageBitmap's bitmap data to a copy of image's bitmap data,
501                // cropped to the source rectangle with formatting.
502                let Some(bitmap_data) =
503                    ImageBitmap::crop_and_transform_bitmap_data(snapshot, sx, sy, sw, sh, options)
504                else {
505                    p.reject_error(realm, Error::InvalidState(None));
506                    return p;
507                };
508
509                let image_bitmap = Self::new(realm, global_scope, bitmap_data);
510                // Step 6.2. Set the origin-clean flag of the imageBitmap's bitmap to the same value
511                // as the origin-clean flag of image's bitmap.
512                image_bitmap.set_origin_clean(canvas.origin_is_clean());
513
514                // Step 6.3. Queue a global task, using the bitmap task source,
515                // to resolve promise with imageBitmap.
516                fullfill_promise_on_bitmap_task_source(&p, &image_bitmap);
517            },
518            ImageBitmapSource::Blob(ref blob) => {
519                // Step 6.1. Let imageData be the result of reading image's data.
520                // If an error occurs during reading of the object, then queue
521                // a global task, using the bitmap task source, to reject promise
522                // with an "InvalidStateError" DOMException and abort these steps.
523                let Ok(bytes) = blob.get_bytes() else {
524                    reject_promise_on_bitmap_task_source(&p);
525                    return p;
526                };
527
528                // Step 6.2. Apply the image sniffing rules to determine the file
529                // format of imageData, with MIME type of image (as given by
530                // image's type attribute) giving the official type.
531                // Step 6.3. If imageData is not in a supported image file format
532                // (e.g., it's not an image at all), or if imageData is corrupted
533                // in some fatal way such that the image dimensions cannot be obtained
534                // (e.g., a vector graphic with no natural size), then queue
535                // a global task, using the bitmap task source, to reject promise
536                // with an "InvalidStateError" DOMException and abort these steps.
537                let Some(raster_image) = pixels::load_from_memory(&bytes, CorsStatus::Safe) else {
538                    reject_promise_on_bitmap_task_source(&p);
539                    return p;
540                };
541
542                // Step 6.4. Set imageBitmap's bitmap data to imageData, cropped
543                // to the source rectangle with formatting.
544                let snapshot = raster_image.as_snapshot();
545                let Some(bitmap_data) =
546                    ImageBitmap::crop_and_transform_bitmap_data(snapshot, sx, sy, sw, sh, options)
547                else {
548                    reject_promise_on_bitmap_task_source(&p);
549                    return p;
550                };
551
552                let image_bitmap = Self::new(realm, global_scope, bitmap_data);
553
554                // Step 6.5. Queue a global task, using the bitmap task source,
555                // to resolve promise with imageBitmap.
556                fullfill_promise_on_bitmap_task_source(&p, &image_bitmap);
557            },
558            ImageBitmapSource::ImageData(ref image_data) => {
559                // Step 6.1. Let buffer be image's data attribute value's [[ViewedArrayBuffer]] internal slot.
560                // Step 6.2. If IsDetachedBuffer(buffer) is true, then return a promise rejected
561                // with an "InvalidStateError" DOMException.
562                if image_data.is_detached(realm) {
563                    p.reject_error(realm, Error::InvalidState(None));
564                    return p;
565                }
566
567                let alpha_mode = SnapshotAlphaMode::Transparent {
568                    premultiplied: false,
569                };
570
571                let snapshot = Snapshot::from_vec(
572                    image_data.get_size().cast(),
573                    SnapshotPixelFormat::RGBA,
574                    alpha_mode,
575                    image_data.to_vec(realm.no_gc()),
576                );
577
578                // Step 6.3. Set imageBitmap's bitmap data to image's image data,
579                // cropped to the source rectangle with formatting.
580                let Some(bitmap_data) =
581                    ImageBitmap::crop_and_transform_bitmap_data(snapshot, sx, sy, sw, sh, options)
582                else {
583                    p.reject_error(realm, Error::InvalidState(None));
584                    return p;
585                };
586
587                let image_bitmap = Self::new(realm, global_scope, bitmap_data);
588
589                // Step 6.4. Queue a global task, using the bitmap task source,
590                // to resolve promise with imageBitmap.
591                fullfill_promise_on_bitmap_task_source(&p, &image_bitmap);
592            },
593            ImageBitmapSource::CSSStyleValue(_) => {
594                // TODO: CSSStyleValue is not part of ImageBitmapSource
595                // <https://html.spec.whatwg.org/multipage/#imagebitmapsource>
596                p.reject_error(realm, Error::NotSupported(None));
597            },
598        }
599
600        // Step 7. Return promise.
601        p
602    }
603}
604
605impl Serializable for ImageBitmap {
606    type Index = ImageBitmapIndex;
607    type Data = SerializableImageBitmap;
608
609    /// <https://html.spec.whatwg.org/multipage/#the-imagebitmap-interface:serialization-steps>
610    fn serialize(&self, _no_gc: &NoGC) -> Result<(ImageBitmapId, Self::Data), ()> {
611        // <https://html.spec.whatwg.org/multipage/#structuredserializeinternal>
612        // Step 19.1. If value has a [[Detached]] internal slot whose value is
613        // true, then throw a "DataCloneError" DOMException.
614        if self.is_detached() {
615            return Err(());
616        }
617
618        // Step 1. If value's origin-clean flag is not set, then throw a
619        // "DataCloneError" DOMException.
620        if !self.origin_is_clean() {
621            return Err(());
622        }
623
624        let Some(bitmap_data) = &*self.bitmap_data.borrow() else {
625            return Err(());
626        };
627
628        // Step 2. Set serialized.[[BitmapData]] to a copy of value's bitmap data.
629        let serialized = SerializableImageBitmap {
630            bitmap_data: bitmap_data.to_shared(),
631        };
632
633        Ok((ImageBitmapId::new(), serialized))
634    }
635
636    /// <https://html.spec.whatwg.org/multipage/#the-imagebitmap-interface:deserialization-steps>
637    fn deserialize(
638        cx: &mut JSContext,
639        owner: &GlobalScope,
640        serialized: Self::Data,
641    ) -> Result<DomRoot<Self>, ()> {
642        // Step 1. Set value's bitmap data to serialized.[[BitmapData]].
643        Ok(ImageBitmap::new(
644            cx,
645            owner,
646            serialized.bitmap_data.to_owned(),
647        ))
648    }
649
650    fn serialized_storage<'a>(
651        data: StructuredData<'a, '_>,
652    ) -> &'a mut Option<FxHashMap<ImageBitmapId, Self::Data>> {
653        match data {
654            StructuredData::Reader(r) => &mut r.image_bitmaps,
655            StructuredData::Writer(w) => &mut w.image_bitmaps,
656        }
657    }
658}
659
660impl Transferable for ImageBitmap {
661    type Index = ImageBitmapIndex;
662    type Data = SerializableImageBitmap;
663
664    /// <https://html.spec.whatwg.org/multipage/#the-imagebitmap-interface:transfer-steps>
665    fn transfer(&self, _cx: &mut JSContext) -> Fallible<(ImageBitmapId, SerializableImageBitmap)> {
666        // <https://html.spec.whatwg.org/multipage/#structuredserializewithtransfer>
667        // Step 5.2. If transferable has a [[Detached]] internal slot and
668        // transferable.[[Detached]] is true, then throw a "DataCloneError"
669        // DOMException.
670        if self.is_detached() {
671            return Err(Error::DataClone(None));
672        }
673
674        // Step 1. If value's origin-clean flag is not set, then throw a
675        // "DataCloneError" DOMException.
676        if !self.origin_is_clean() {
677            return Err(Error::DataClone(None));
678        }
679
680        let Some(bitmap_data) = self.bitmap_data.borrow_mut().take() else {
681            return Err(Error::DataClone(None));
682        };
683
684        // Step 2. Set dataHolder.[[BitmapData]] to value's bitmap data.
685        // Step 3. Unset value's bitmap data.
686        let transferred = SerializableImageBitmap {
687            bitmap_data: bitmap_data.to_shared(),
688        };
689
690        Ok((ImageBitmapId::new(), transferred))
691    }
692
693    /// <https://html.spec.whatwg.org/multipage/#the-imagebitmap-interface:transfer-receiving-steps>
694    fn transfer_receive(
695        cx: &mut JSContext,
696        owner: &GlobalScope,
697        _: ImageBitmapId,
698        transferred: SerializableImageBitmap,
699    ) -> Result<DomRoot<Self>, ()> {
700        // Step 1. Set value's bitmap data to serialized.[[BitmapData]].
701        Ok(ImageBitmap::new(
702            cx,
703            owner,
704            transferred.bitmap_data.to_owned(),
705        ))
706    }
707
708    fn serialized_storage<'a>(
709        data: StructuredData<'a, '_>,
710    ) -> &'a mut Option<FxHashMap<ImageBitmapId, Self::Data>> {
711        match data {
712            StructuredData::Reader(r) => &mut r.transferred_image_bitmaps,
713            StructuredData::Writer(w) => &mut w.transferred_image_bitmaps,
714        }
715    }
716}
717
718impl ImageBitmapMethods<crate::DomTypeHolder> for ImageBitmap {
719    /// <https://html.spec.whatwg.org/multipage/#dom-imagebitmap-height>
720    fn Height(&self) -> u32 {
721        // Step 1. If this's [[Detached]] internal slot's value is true, then return 0.
722        if self.is_detached() {
723            return 0;
724        }
725
726        // Step 2. Return this's height, in CSS pixels.
727        self.bitmap_data
728            .borrow()
729            .as_ref()
730            .unwrap()
731            .size()
732            .cast()
733            .height
734    }
735
736    /// <https://html.spec.whatwg.org/multipage/#dom-imagebitmap-width>
737    fn Width(&self) -> u32 {
738        // Step 1. If this's [[Detached]] internal slot's value is true, then return 0.
739        if self.is_detached() {
740            return 0;
741        }
742
743        // Step 2. Return this's width, in CSS pixels.
744        self.bitmap_data
745            .borrow()
746            .as_ref()
747            .unwrap()
748            .size()
749            .cast()
750            .width
751    }
752
753    /// <https://html.spec.whatwg.org/multipage/#dom-imagebitmap-close>
754    fn Close(&self) {
755        // Step 1. Set this's [[Detached]] internal slot value to true.
756        // Step 2. Unset this's bitmap data.
757        // NOTE: The existence of the bitmap data is the internal slot in our implementation
758        self.bitmap_data.borrow_mut().take();
759    }
760}