OffscreenCanvas.transferToImageBitmap() context specific code should …

…exist in the context

https://bugs.webkit.org/show_bug.cgi?id=275105
rdar://129217576

Reviewed by Antti Koivisto.

OffscreenCanvas::transferToImageBitmap() has code conditionalized to
different canvas rendering contexts. Move this code to
the contexts, into overrides of new virtual function
CanvasRenderingContext::transferToImageBuffer().

This way the contexts are able to manage the buffers themselves in
future commits.

Fix the error-case where the out-of-memory causes an exception instead
of null ImageBitmap for all backends. The exception should be
DOM UnknownError, that is used to signify out-of-memory.

* Source/WebCore/html/CanvasBase.h:
* Source/WebCore/html/OffscreenCanvas.cpp:
(WebCore::OffscreenCanvas::transferToImageBitmap):
* Source/WebCore/html/canvas/CanvasRenderingContext.cpp:
(WebCore::CanvasRenderingContext::transferToImageBuffer):
* Source/WebCore/html/canvas/CanvasRenderingContext.h:
* Source/WebCore/html/canvas/GPUCanvasContext.h:
* Source/WebCore/html/canvas/GPUCanvasContextCocoa.h:
* Source/WebCore/html/canvas/GPUCanvasContextCocoa.mm:
(WebCore::GPUCanvasContextCocoa::transferToImageBuffer):
(WebCore::GPUCanvasContextCocoa::getCurrentTextureAsImageBitmap): Deleted.
* Source/WebCore/html/canvas/ImageBitmapRenderingContext.cpp:
(WebCore::ImageBitmapRenderingContext::setOutputBitmap):
(WebCore::ImageBitmapRenderingContext::setBlank):
(WebCore::ImageBitmapRenderingContext::transferToImageBuffer):
* Source/WebCore/html/canvas/ImageBitmapRenderingContext.h:
* Source/WebCore/html/canvas/OffscreenCanvasRenderingContext2D.cpp:
(WebCore::OffscreenCanvasRenderingContext2D::transferToImageBuffer):
* Source/WebCore/html/canvas/OffscreenCanvasRenderingContext2D.h:
* Source/WebCore/html/canvas/WebGLRenderingContextBase.cpp:
(WebCore::WebGLRenderingContextBase::transferToImageBuffer):
(WebCore::WebGLRenderingContextBase::markDrawingBuffersDirtyAfterTransfer): Deleted.
* Source/WebCore/html/canvas/WebGLRenderingContextBase.h:

Canonical link: https://commits.webkit.org/279872@main

LayoutTests/fast/canvas/offscreen-giant-transfer-to-imagebitmap-expected.txt

@@ -1,2 +1,42 @@
 CONSOLE MESSAGE: Canvas area exceeds the maximum limit (width * height > 268435456).
+CONSOLE MESSAGE: Canvas area exceeds the maximum limit (width * height > 268435456).
+CONSOLE MESSAGE: Canvas area exceeds the maximum limit (width * height > 268435456).
+CONSOLE MESSAGE: Canvas area exceeds the maximum limit (width * height > 268435456).
+Testing height: 100 type: none
+Got exception: "InvalidStateError: The object is in an invalid state."
+Testing height: 100 type: 2d
+Got context: "[object OffscreenCanvasRenderingContext2D]"
+Got result with size: 100x100
+Testing height: 100 type: webgl
+Got context: "[object WebGLRenderingContext]"
+Got result with size: 100x100
+Testing height: 100 type: webgl2
+Got context: "[object WebGL2RenderingContext]"
+Got result with size: 100x100
+Testing height: 100 type: webgpu
+Got context: "null"
+Got exception: "InvalidStateError: The object is in an invalid state."
+Testing height: 100 type: bitmaprenderer
+Got context: "[object ImageBitmapRenderingContext]"
+Got result with size: 100x100
+Testing height: 100000000 type: none
+Got exception: "InvalidStateError: The object is in an invalid state."
+Testing height: 100000000 type: 2d
+Got context: "[object OffscreenCanvasRenderingContext2D]"
+Got exception: "UnknownError: The operation failed for an unknown transient reason (e.g. out of memory)."
+Testing height: 100000000 type: webgl
+Got context: "[object WebGLRenderingContext]"
+Got exception: "UnknownError: The operation failed for an unknown transient reason (e.g. out of memory)."
+Testing height: 100000000 type: webgl2
+Got context: "[object WebGL2RenderingContext]"
+Got exception: "UnknownError: The operation failed for an unknown transient reason (e.g. out of memory)."
+Testing height: 100000000 type: webgpu
+Got context: "null"
+Got exception: "InvalidStateError: The object is in an invalid state."
+Testing height: 100000000 type: bitmaprenderer
+Got context: "[object ImageBitmapRenderingContext]"
+Got exception: "UnknownError: The operation failed for an unknown transient reason (e.g. out of memory)."
+PASS successfullyParsed is true
+
+TEST COMPLETE
 

LayoutTests/fast/canvas/offscreen-giant-transfer-to-imagebitmap.html

@@ -1,11 +1,36 @@
+<body>
+<script src="../../resources/js-test.js"></script>
 <script>
-  onload = () => {
-    if (window.testRunner) {
-        testRunner.dumpAsText();
+function runTest() {
+    if (!window.OffscreenCanvas) {
+        debug("OffscreenCanvas not enabled");
+        return;
     }
-    let offscreenCanvas = new OffscreenCanvas(1, 100000000);
-    offscreenCanvas.getContext('2d');
-    offscreenCanvas.width = 100;
-    offscreenCanvas.transferToImageBitmap();
-  }
+    let types = ["none", "2d", "webgl", "webgl2", "webgpu", "bitmaprenderer"];
+    let heights = [100, 100000000];
+    for (let height of heights) {
+        for (let type of types) {
+            debug(`Testing height: ${height} type: ${type} `);
+            let canvas = new OffscreenCanvas(1, height);
+            if (type != "none") {
+                let ctx = canvas.getContext(type);
+                debug(`Got context: "${ctx}"`);
+            }
+            canvas.width = 100;
+            try {
+                let result = canvas.transferToImageBitmap();
+                if (result)
+                    debug(`Got result with size: ${result.width}x${result.height}`);
+                else
+                    debug(`Got result: "${result}"`);
+            } catch (e) {
+                debug(`Got exception: "${e}"`);
+            }
+            delete ctx;
+            delete canvas;
+        }
+    }
+}
+runTest();
 </script>
+</body>

LayoutTests/platform/ios/fast/canvas/offscreen-giant-transfer-to-imagebitmap-expected.txt

@@ -1,2 +1,43 @@
 CONSOLE MESSAGE: Canvas area exceeds the maximum limit (width * height > 67108864).
+CONSOLE MESSAGE: Canvas area exceeds the maximum limit (width * height > 67108864).
+CONSOLE MESSAGE: Canvas area exceeds the maximum limit (width * height > 67108864).
+CONSOLE MESSAGE: Canvas area exceeds the maximum limit (width * height > 67108864).
+CONSOLE MESSAGE: Canvas area exceeds the maximum limit (width * height > 67108864).
+Testing height: 100 type: none
+Got exception: "InvalidStateError: The object is in an invalid state."
+Testing height: 100 type: 2d
+Got context: "[object OffscreenCanvasRenderingContext2D]"
+Got result with size: 100x100
+Testing height: 100 type: webgl
+Got context: "[object WebGLRenderingContext]"
+Got result with size: 100x100
+Testing height: 100 type: webgl2
+Got context: "[object WebGL2RenderingContext]"
+Got result with size: 100x100
+Testing height: 100 type: webgpu
+Got context: "[object GPUCanvasContext]"
+Got result with size: 100x100
+Testing height: 100 type: bitmaprenderer
+Got context: "[object ImageBitmapRenderingContext]"
+Got result with size: 100x100
+Testing height: 100000000 type: none
+Got exception: "InvalidStateError: The object is in an invalid state."
+Testing height: 100000000 type: 2d
+Got context: "[object OffscreenCanvasRenderingContext2D]"
+Got exception: "UnknownError: The operation failed for an unknown transient reason (e.g. out of memory)."
+Testing height: 100000000 type: webgl
+Got context: "[object WebGLRenderingContext]"
+Got exception: "UnknownError: The operation failed for an unknown transient reason (e.g. out of memory)."
+Testing height: 100000000 type: webgl2
+Got context: "[object WebGL2RenderingContext]"
+Got exception: "UnknownError: The operation failed for an unknown transient reason (e.g. out of memory)."
+Testing height: 100000000 type: webgpu
+Got context: "[object GPUCanvasContext]"
+Got exception: "UnknownError: The operation failed for an unknown transient reason (e.g. out of memory)."
+Testing height: 100000000 type: bitmaprenderer
+Got context: "[object ImageBitmapRenderingContext]"
+Got exception: "UnknownError: The operation failed for an unknown transient reason (e.g. out of memory)."
+PASS successfullyParsed is true
+
+TEST COMPLETE
 

LayoutTests/platform/mac-wk2/fast/canvas/offscreen-giant-transfer-to-imagebitmap-expected.txt

@@ -0,0 +1,43 @@
+CONSOLE MESSAGE: Canvas area exceeds the maximum limit (width * height > 268435456).
+CONSOLE MESSAGE: Canvas area exceeds the maximum limit (width * height > 268435456).
+CONSOLE MESSAGE: Canvas area exceeds the maximum limit (width * height > 268435456).
+CONSOLE MESSAGE: Canvas area exceeds the maximum limit (width * height > 268435456).
+CONSOLE MESSAGE: Canvas area exceeds the maximum limit (width * height > 268435456).
+Testing height: 100 type: none
+Got exception: "InvalidStateError: The object is in an invalid state."
+Testing height: 100 type: 2d
+Got context: "[object OffscreenCanvasRenderingContext2D]"
+Got result with size: 100x100
+Testing height: 100 type: webgl
+Got context: "[object WebGLRenderingContext]"
+Got result with size: 100x100
+Testing height: 100 type: webgl2
+Got context: "[object WebGL2RenderingContext]"
+Got result with size: 100x100
+Testing height: 100 type: webgpu
+Got context: "[object GPUCanvasContext]"
+Got result with size: 100x100
+Testing height: 100 type: bitmaprenderer
+Got context: "[object ImageBitmapRenderingContext]"
+Got result with size: 100x100
+Testing height: 100000000 type: none
+Got exception: "InvalidStateError: The object is in an invalid state."
+Testing height: 100000000 type: 2d
+Got context: "[object OffscreenCanvasRenderingContext2D]"
+Got exception: "UnknownError: The operation failed for an unknown transient reason (e.g. out of memory)."
+Testing height: 100000000 type: webgl
+Got context: "[object WebGLRenderingContext]"
+Got exception: "UnknownError: The operation failed for an unknown transient reason (e.g. out of memory)."
+Testing height: 100000000 type: webgl2
+Got context: "[object WebGL2RenderingContext]"
+Got exception: "UnknownError: The operation failed for an unknown transient reason (e.g. out of memory)."
+Testing height: 100000000 type: webgpu
+Got context: "[object GPUCanvasContext]"
+Got exception: "UnknownError: The operation failed for an unknown transient reason (e.g. out of memory)."
+Testing height: 100000000 type: bitmaprenderer
+Got context: "[object ImageBitmapRenderingContext]"
+Got exception: "UnknownError: The operation failed for an unknown transient reason (e.g. out of memory)."
+PASS successfullyParsed is true
+
+TEST COMPLETE
+

Source/WebCore/html/CanvasBase.h

@@ -153,7 +153,9 @@ class CanvasBase {
     void setNoiseInjectionSalt(NoiseInjectionHashSalt salt) { m_canvasNoiseHashSalt = salt; }
     bool havePendingCanvasNoiseInjection() const { return m_canvasNoiseInjection.haveDirtyRects(); }
 
+    // FIXME(https://bugs.webkit.org/show_bug.cgi?id=275100): The image buffer from CanvasBase should be moved to CanvasRenderingContext2DBase.
     virtual bool hasCreatedImageBuffer() const { return false; }
+    RefPtr<ImageBuffer> allocateImageBuffer() const;
 
 protected:
     explicit CanvasBase(IntSize, const std::optional<NoiseInjectionHashSalt>&);
@@ -163,7 +165,6 @@ class CanvasBase {
     virtual void setSize(const IntSize&);
 
     RefPtr<ImageBuffer> setImageBuffer(RefPtr<ImageBuffer>&&) const;
-    RefPtr<ImageBuffer> allocateImageBuffer() const;
     String lastFillText() const { return m_lastFillText; }
     void addCanvasNeedingPreparationForDisplayOrFlush();
     void removeCanvasNeedingPreparationForDisplayOrFlush();

Source/WebCore/html/OffscreenCanvas.cpp

@@ -304,68 +304,13 @@ ExceptionOr<RefPtr<ImageBitmap>> OffscreenCanvas::transferToImageBitmap()
 {
     if (m_detached || !m_context)
         return Exception { ExceptionCode::InvalidStateError };
-
-    if (is<OffscreenCanvasRenderingContext2D>(*m_context) || is<ImageBitmapRenderingContext>(*m_context)) {
-        if (!width() || !height())
-            return { RefPtr<ImageBitmap> { nullptr } };
-
-        if (!m_hasCreatedImageBuffer) {
-            auto buffer = allocateImageBuffer();
-            if (!buffer)
-                return { RefPtr<ImageBitmap> { nullptr } };
-            return { ImageBitmap::create(buffer.releaseNonNull(), originClean()) };
-        }
-
-        if (!buffer())
-            return { RefPtr<ImageBitmap> { nullptr } };
-
-        RefPtr<ImageBuffer> bitmap;
-        if (RefPtr context = dynamicDowncast<OffscreenCanvasRenderingContext2D>(*m_context)) {
-            // As the canvas context state is stored in GraphicsContext, which is owned
-            // by buffer(), to avoid resetting the context state, we have to make a copy and
-            // clear the original buffer rather than returning the original buffer.
-            bitmap = buffer()->clone();
-            context->clearCanvas();
-        } else {
-            // ImageBitmapRenderingContext doesn't use the context state, so we can just take its
-            // buffer, and then call transferFromImageBitmap(nullptr) which will trigger it to allocate
-            // a new blank bitmap.
-            bitmap = buffer();
-            downcast<ImageBitmapRenderingContext>(*m_context).transferFromImageBitmap(nullptr);
-        }
-        clearCopiedImage();
-        if (!bitmap)
-            return { RefPtr<ImageBitmap> { nullptr } };
-        return { ImageBitmap::create(bitmap.releaseNonNull(), originClean(), false, false) };
-    }
-
-#if ENABLE(WEBGL)
-    if (auto* webGLContext = dynamicDowncast<WebGLRenderingContextBase>(*m_context)) {
-        // FIXME: We're supposed to create an ImageBitmap using the backing
-        // store from this canvas (or its context), but for now we'll just
-        // create a new bitmap and paint into it.
-        auto buffer = allocateImageBuffer();
-        if (!buffer)
-            return { RefPtr<ImageBitmap> { nullptr } };
-        if (webGLContext->compositingResultsNeedUpdating())
-            webGLContext->prepareForDisplay();
-        RefPtr gc3d = webGLContext->graphicsContextGL();
-        gc3d->drawSurfaceBufferToImageBuffer(GraphicsContextGL::SurfaceBuffer::DisplayBuffer, *buffer);
-        webGLContext->markDrawingBuffersDirtyAfterTransfer();
-        return { ImageBitmap::create(buffer.releaseNonNull(), originClean()) };
-    }
-#endif
-
-    if (auto* context = dynamicDowncast<GPUCanvasContext>(*m_context)) {
-        auto buffer = allocateImageBuffer();
-        if (!buffer)
-            return Exception { ExceptionCode::OutOfMemoryError };
-
-        Ref<ImageBuffer> bufferRef = buffer.releaseNonNull();
-        return context->getCurrentTextureAsImageBitmap(bufferRef, originClean());
-    }
-
-    return Exception { ExceptionCode::NotSupportedError };
+    if (size().isEmpty())
+        return { RefPtr<ImageBitmap> { nullptr } };
+    clearCopiedImage();
+    RefPtr buffer = m_context->transferToImageBuffer();
+    if (!buffer)
+        return Exception { ExceptionCode::UnknownError }; // UnknownError is used for DOM out-of-memory.
+    return { ImageBitmap::create(buffer.releaseNonNull(), originClean()) };
 }
 
 static String toEncodingMimeType(const String& mimeType)

Source/WebCore/html/canvas/CanvasRenderingContext.cpp

@@ -20,7 +20,7 @@
  * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY
  * OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 
+ * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  */
 
 #include "config.h"
@@ -108,6 +108,12 @@ void CanvasRenderingContext::setContentsToLayer(GraphicsLayer& layer)
     layer.setContentsDisplayDelegate(layerContentsDisplayDelegate(), GraphicsLayer::ContentsLayerPurpose::Canvas);
 }
 
+RefPtr<ImageBuffer> CanvasRenderingContext::transferToImageBuffer()
+{
+    ASSERT_NOT_REACHED(); // Implemented and called only for offscreen capable contexts.
+    return nullptr;
+}
+
 PixelFormat CanvasRenderingContext::pixelFormat() const
 {
     return PixelFormat::BGRA8;

Source/WebCore/html/canvas/CanvasRenderingContext.h

@@ -96,6 +96,9 @@ class CanvasRenderingContext : public ScriptWrappable, public CanMakeWeakPtr<Can
     virtual RefPtr<GraphicsLayerContentsDisplayDelegate> layerContentsDisplayDelegate();
     virtual void setContentsToLayer(GraphicsLayer&);
 
+    // Returns the drawing buffer and runs the compositing steps of transferToImageBitmap.
+    virtual RefPtr<ImageBuffer> transferToImageBuffer();
+
     bool hasActiveInspectorCanvasCallTracer() const { return m_hasActiveInspectorCanvasCallTracer; }
     void setHasActiveInspectorCanvasCallTracer(bool hasActiveInspectorCanvasCallTracer) { m_hasActiveInspectorCanvasCallTracer = hasActiveInspectorCanvasCallTracer; }
 

Source/WebCore/html/canvas/GPUCanvasContext.h

@@ -60,7 +60,6 @@ class GPUCanvasContext : public GPUBasedCanvasRenderingContext {
     virtual ExceptionOr<void> configure(GPUCanvasConfiguration&&) = 0;
     virtual void unconfigure() = 0;
     virtual ExceptionOr<RefPtr<GPUTexture>> getCurrentTexture() = 0;
-    virtual ExceptionOr<RefPtr<ImageBitmap>> getCurrentTextureAsImageBitmap(ImageBuffer&, bool originClean) = 0;
 
     bool isWebGPU() const override { return true; }
 

Source/WebCore/html/canvas/GPUCanvasContextCocoa.h

@@ -72,7 +72,7 @@ class GPUCanvasContextCocoa final : public GPUCanvasContext {
     ExceptionOr<void> configure(GPUCanvasConfiguration&&) override;
     void unconfigure() override;
     ExceptionOr<RefPtr<GPUTexture>> getCurrentTexture() override;
-    ExceptionOr<RefPtr<ImageBitmap>> getCurrentTextureAsImageBitmap(ImageBuffer&, bool originClean) override;
+    RefPtr<ImageBuffer> transferToImageBuffer() override;
 
     bool isWebGPU() const override { return true; }
 

Source/WebCore/html/canvas/GPUCanvasContextCocoa.mm

@@ -199,20 +199,20 @@ static GPUIntegerCoordinate getCanvasHeight(const GPUCanvasContext::CanvasType&
     return canvasBase().buffer();
 }
 
-ExceptionOr<RefPtr<ImageBitmap>> GPUCanvasContextCocoa::getCurrentTextureAsImageBitmap(ImageBuffer& buffer, bool originClean)
+RefPtr<ImageBuffer> GPUCanvasContextCocoa::transferToImageBuffer()
 {
+    auto buffer = canvasBase().allocateImageBuffer();
+    if (!buffer)
+        return nullptr;
+    Ref<ImageBuffer> bufferRef = buffer.releaseNonNull();
     if (m_configuration) {
-        buffer.flushDrawingContext();
         if (m_compositorIntegration)
-            m_compositorIntegration->paintCompositedResultsToCanvas(buffer, m_configuration->frameCount);
+            m_compositorIntegration->paintCompositedResultsToCanvas(bufferRef, m_configuration->frameCount);
         m_currentTexture = nullptr;
         if (m_presentationContext)
             m_presentationContext->present(true);
-
-        return { ImageBitmap::create(buffer, originClean) };
     }
-
-    return { ImageBitmap::create(buffer, originClean) };
+    return bufferRef;
 }
 
 GPUCanvasContext::CanvasType GPUCanvasContextCocoa::canvas()