| /* |
| * Copyright (C) 2017 Apple Inc. All rights reserved. |
| * |
| * Redistribution and use in source and binary forms, with or without |
| * modification, are permitted provided that the following conditions |
| * are met: |
| * 1. Redistributions of source code must retain the above copyright |
| * notice, this list of conditions and the following disclaimer. |
| * 2. Redistributions in binary form must reproduce the above copyright |
| * notice, this list of conditions and the following disclaimer in the |
| * documentation and/or other materials provided with the distribution. |
| * |
| * THIS SOFTWARE IS PROVIDED BY APPLE INC. AND ITS CONTRIBUTORS ``AS IS'' |
| * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, |
| * THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR |
| * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL APPLE INC. OR ITS CONTRIBUTORS |
| * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR |
| * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF |
| * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR 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. |
| */ |
| |
| #include "config.h" |
| #include "ImageBitmapRenderingContext.h" |
| |
| #include "ImageBitmap.h" |
| #include "ImageBuffer.h" |
| #include "InspectorInstrumentation.h" |
| |
| namespace WebCore { |
| |
| #if USE(IOSURFACE_CANVAS_BACKING_STORE) || ENABLE(ACCELERATED_2D_CANVAS) |
| static RenderingMode bufferRenderingMode = Accelerated; |
| #else |
| static RenderingMode bufferRenderingMode = Unaccelerated; |
| #endif |
| |
| std::unique_ptr<ImageBitmapRenderingContext> ImageBitmapRenderingContext::create(CanvasBase& canvas, ImageBitmapRenderingContextSettings&& settings) |
| { |
| auto renderingContext = std::unique_ptr<ImageBitmapRenderingContext>(new ImageBitmapRenderingContext(canvas, WTFMove(settings))); |
| |
| InspectorInstrumentation::didCreateCanvasRenderingContext(*renderingContext); |
| |
| return renderingContext; |
| } |
| |
| ImageBitmapRenderingContext::ImageBitmapRenderingContext(CanvasBase& canvas, ImageBitmapRenderingContextSettings&& settings) |
| : CanvasRenderingContext(canvas) |
| , m_settings(WTFMove(settings)) |
| { |
| setOutputBitmap(nullptr); |
| } |
| |
| ImageBitmapRenderingContext::~ImageBitmapRenderingContext() = default; |
| |
| HTMLCanvasElement* ImageBitmapRenderingContext::canvas() const |
| { |
| auto& base = canvasBase(); |
| if (!is<HTMLCanvasElement>(base)) |
| return nullptr; |
| return &downcast<HTMLCanvasElement>(base); |
| } |
| |
| bool ImageBitmapRenderingContext::isAccelerated() const |
| { |
| return bufferRenderingMode == Accelerated; |
| } |
| |
| void ImageBitmapRenderingContext::setOutputBitmap(RefPtr<ImageBitmap> imageBitmap) |
| { |
| // 1. If a bitmap argument was not provided, then: |
| |
| if (!imageBitmap) { |
| |
| // 1.1. Set context's bitmap mode to blank. |
| |
| m_bitmapMode = BitmapMode::Blank; |
| |
| // 1.2. Let canvas be the canvas element to which context is bound. |
| |
| // 1.3. Set context's output bitmap to be transparent black with an |
| // intrinsic width equal to the numeric value of canvas's width attribute |
| // and an intrinsic height equal to the numeric value of canvas's height |
| // attribute, those values being interpreted in CSS pixels. |
| |
| // FIXME: What is the point of creating a full size transparent buffer that |
| // can never be changed? Wouldn't a 1x1 buffer give the same rendering? The |
| // only reason I can think of is toDataURL(), but that doesn't seem like |
| // a good enough argument to waste memory. |
| |
| canvas()->setImageBufferAndMarkDirty(ImageBuffer::create(FloatSize(canvas()->width(), canvas()->height()), bufferRenderingMode)); |
| |
| // 1.4. Set the output bitmap's origin-clean flag to true. |
| |
| canvas()->setOriginClean(); |
| return; |
| } |
| |
| // 2. If a bitmap argument was provided, then: |
| |
| // 2.1. Set context's bitmap mode to valid. |
| |
| m_bitmapMode = BitmapMode::Valid; |
| |
| // 2.2. Set context's output bitmap to refer to the same underlying |
| // bitmap data as bitmap, without making a copy. |
| // Note: the origin-clean flag of bitmap is included in the |
| // bitmap data to be referenced by context's output bitmap. |
| |
| if (imageBitmap->originClean()) |
| canvas()->setOriginClean(); |
| else |
| canvas()->setOriginTainted(); |
| canvas()->setImageBufferAndMarkDirty(imageBitmap->transferOwnershipAndClose()); |
| } |
| |
| ExceptionOr<void> ImageBitmapRenderingContext::transferFromImageBitmap(RefPtr<ImageBitmap> imageBitmap) |
| { |
| // 1. Let bitmapContext be the ImageBitmapRenderingContext object on which |
| // the transferFromImageBitmap() method was called. |
| |
| // 2. If imageBitmap is null, then run the steps to set an ImageBitmapRenderingContext's |
| // output bitmap, with bitmapContext as the context argument and no bitmap argument, |
| // then abort these steps. |
| |
| if (!imageBitmap) { |
| setOutputBitmap(nullptr); |
| return { }; |
| } |
| |
| // 3. If the value of imageBitmap's [[Detached]] internal slot is set to true, |
| // then throw an "InvalidStateError" DOMException and abort these steps. |
| |
| if (imageBitmap->isDetached()) |
| return Exception { InvalidStateError }; |
| |
| // 4. Run the steps to set an ImageBitmapRenderingContext's output bitmap, |
| // with the context argument equal to bitmapContext, and the bitmap |
| // argument referring to imageBitmap's underlying bitmap data. |
| |
| setOutputBitmap(imageBitmap); |
| |
| // 5. Set the value of imageBitmap's [[Detached]] internal slot to true. |
| // 6. Unset imageBitmap's bitmap data. |
| |
| // Note that the algorithm in the specification is currently a bit |
| // muddy here. The setOutputBitmap step above had to transfer ownership |
| // from the imageBitmap to this object, which requires a detach and unset, |
| // so this step isn't necessary, but we'll do it anyway. |
| |
| imageBitmap->close(); |
| |
| return { }; |
| } |
| |
| } |