Implementation of 2D canvas context lost/restored events

Source/platform/graphics/ImageBuffer.cpp

 /*
  * Copyright (c) 2008, Google Inc. All rights reserved.
  * Copyright (C) 2009 Dirk Schulze <krit@webkit.org>
  * Copyright (C) 2010 Torch Mobile (Beijing) Co. Ltd. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions are
  * met:
  *
  *     * Redistributions of source code must retain the above copyright
@@ skipping 20 matching lines @@
  */
 
 #include "config.h"
 #include "platform/graphics/ImageBuffer.h"
 
 #include "platform/MIMETypeRegistry.h"
 #include "platform/geometry/IntRect.h"
 #include "platform/graphics/BitmapImage.h"
 #include "platform/graphics/GraphicsContext.h"
 #include "platform/graphics/GraphicsTypes3D.h"
+#include "platform/graphics/ImageBufferClient.h"
 #include "platform/graphics/UnacceleratedImageBufferSurface.h"
 #include "platform/graphics/gpu/DrawingBuffer.h"
 #include "platform/graphics/gpu/Extensions3DUtil.h"
 #include "platform/graphics/skia/NativeImageSkia.h"
 #include "platform/graphics/skia/SkiaUtils.h"
 #include "platform/image-encoders/skia/JPEGImageEncoder.h"
 #include "platform/image-encoders/skia/PNGImageEncoder.h"
 #include "platform/image-encoders/skia/WEBPImageEncoder.h"
 #include "public/platform/Platform.h"
 #include "public/platform/WebExternalTextureMailbox.h"
@@ skipping 18 matching lines @@
 PassOwnPtr<ImageBuffer> ImageBuffer::create(const IntSize& size, OpacityMode opacityMode)
 {
     OwnPtr<ImageBufferSurface> surface = adoptPtr(new UnacceleratedImageBufferSurface(size, opacityMode));
     if (!surface->isValid())
         return nullptr;
     return adoptPtr(new ImageBuffer(surface.release()));
 }
 
 ImageBuffer::ImageBuffer(PassOwnPtr<ImageBufferSurface> surface)
     : m_surface(surface)
+    , m_client(0)
 {
+    m_surface->setImageBuffer(this);
     if (m_surface->canvas()) {
         m_context = adoptPtr(new GraphicsContext(m_surface->canvas()));
         m_context->setCertainlyOpaque(m_surface->opacityMode() == Opaque);
         m_context->setAccelerated(m_surface->isAccelerated());
     }
 }
 
 ImageBuffer::~ImageBuffer()
 {
 }
 
 GraphicsContext* ImageBuffer::context() const
 {
+    if (!isSurfaceValid())
+        return 0;
     m_surface->willUse();
     ASSERT(m_context.get());
     return m_context.get();
 }
 
 const SkBitmap& ImageBuffer::bitmap() const
 {
     m_surface->willUse();
     return m_surface->bitmap();
 }
 
-bool ImageBuffer::isValid() const
+bool ImageBuffer::isSurfaceValid() const
 {
     return m_surface->isValid();
 }
 
+bool ImageBuffer::restoreSurface() const
+{
+    return m_surface->isValid() || m_surface->restore();
+}
+
+void ImageBuffer::notifySurfaceInvalid()
+{
+    if (m_client)
+        m_client->notifySurfaceInvalid();
+}
+
 static SkBitmap deepSkBitmapCopy(const SkBitmap& bitmap)
 {
     SkBitmap tmp;
     if (!bitmap.deepCopyTo(&tmp))
         bitmap.copyTo(&tmp, bitmap.colorType());
 
     return tmp;
 }
 
 PassRefPtr<Image> ImageBuffer::copyImage(BackingStoreCopy copyBehavior, ScaleBehavior) const
 {
-    if (!isValid())
+    if (!isSurfaceValid())
         return BitmapImage::create(NativeImageSkia::create());
 
     const SkBitmap& bitmap = m_surface->bitmap();
     return BitmapImage::create(NativeImageSkia::create(copyBehavior == CopyBackingStore ? deepSkBitmapCopy(bitmap) : bitmap));
 }
 
 BackingStoreCopy ImageBuffer::fastCopyImageMode()
 {
     return DontCopyBackingStore;
 }
 
 blink::WebLayer* ImageBuffer::platformLayer() const
 {
     return m_surface->layer();
 }
 
 bool ImageBuffer::copyToPlatformTexture(blink::WebGraphicsContext3D* context, Platform3DObject texture, GLenum internalFormat, GLenum destType, GLint level, bool premultiplyAlpha, bool flipY)
 {
-    if (!m_surface->isAccelerated() || !platformLayer() || !isValid())
+    if (!m_surface->isAccelerated() || !platformLayer() || !isSurfaceValid())
         return false;
 
     if (!Extensions3DUtil::canUseCopyTextureCHROMIUM(internalFormat, destType, level))
         return false;
 
     OwnPtr<blink::WebGraphicsContext3DProvider> provider = adoptPtr(blink::Platform::current()->createSharedOffscreenGraphicsContext3DProvider());
     if (!provider)
         return false;
     blink::WebGraphicsContext3D* sharedContext = provider->context3d();
     if (!sharedContext || !sharedContext->makeContextCurrent())
@@ skipping 60 matching lines @@
     Platform3DObject tex = m_surface->getBackingTexture();
     if (!context3D || !tex)
         return false;
     m_surface->invalidateCachedBitmap();
     return drawingBuffer->copyToPlatformTexture(context3D, tex, GL_RGBA,
         GL_UNSIGNED_BYTE, 0, true, false);
 }
 
 void ImageBuffer::draw(GraphicsContext* context, const FloatRect& destRect, const FloatRect& srcRect, CompositeOperator op, blink::WebBlendMode blendMode)
 {
-    if (!isValid())
+    if (!isSurfaceValid())
         return;
 
     SkBitmap bitmap = m_surface->bitmap();
     // For ImageBufferSurface that enables cachedBitmap, Use the cached Bitmap for CPU side usage
     // if it is available, otherwise generate and use it.
-    if (!context->isAccelerated() && m_surface->isAccelerated() && m_surface->cachedBitmapEnabled() && m_surface->isValid()) {
+    if (!context->isAccelerated() && m_surface->isAccelerated() && m_surface->cachedBitmapEnabled() && isSurfaceValid()) {
         m_surface->updateCachedBitmapIfNeeded();
         bitmap = m_surface->cachedBitmap();
     }
 
     RefPtr<Image> image = BitmapImage::create(NativeImageSkia::create(drawNeedsCopy(m_context.get(), context) ? deepSkBitmapCopy(bitmap) : bitmap));
 
     context->drawImage(image.get(), destRect, srcRect, op, blendMode, DoNotRespectImageOrientation);
 }
 
 void ImageBuffer::flush()
 {
     if (m_surface->canvas()) {
         m_surface->canvas()->flush();
     }
 }
 
 void ImageBuffer::drawPattern(GraphicsContext* context, const FloatRect& srcRect, const FloatSize& scale,
     const FloatPoint& phase, CompositeOperator op, const FloatRect& destRect, blink::WebBlendMode blendMode, const IntSize& repeatSpacing)
 {
-    if (!isValid())
+    if (!isSurfaceValid())
         return;
 
     const SkBitmap& bitmap = m_surface->bitmap();
     RefPtr<Image> image = BitmapImage::create(NativeImageSkia::create(drawNeedsCopy(m_context.get(), context) ? deepSkBitmapCopy(bitmap) : bitmap));
     image->drawPattern(context, srcRect, scale, phase, op, destRect, blendMode, repeatSpacing);
 }
 
 void ImageBuffer::transformColorSpace(ColorSpace srcColorSpace, ColorSpace dstColorSpace)
 {
     const uint8_t* lookUpTable = ColorSpaceUtilities::getConversionLUT(dstColorSpace, srcColorSpace);
     if (!lookUpTable)
         return;
 
     // FIXME: Disable color space conversions on accelerated canvases (for now).
-    if (context()->isAccelerated() || !isValid())
+    if (context()->isAccelerated() || !isSurfaceValid())
         return;
 
     const SkBitmap& bitmap = m_surface->bitmap();
     if (bitmap.isNull())
         return;
 
     ASSERT(bitmap.colorType() == kPMColor_SkColorType);
     IntSize size = m_surface->size();
     SkAutoLockPixels bitmapLock(bitmap);
     for (int y = 0; y < size.height(); ++y) {
@@ skipping 36 matching lines @@
 
     SkAlphaType alphaType = (multiplied == Premultiplied) ? kPremul_SkAlphaType : kUnpremul_SkAlphaType;
     SkImageInfo info = SkImageInfo::Make(rect.width(), rect.height(), kRGBA_8888_SkColorType, alphaType);
 
     context->readPixels(info, result->data(), 4 * rect.width(), rect.x(), rect.y());
     return result.release();
 }
 
 PassRefPtr<Uint8ClampedArray> ImageBuffer::getUnmultipliedImageData(const IntRect& rect) const
 {
-    if (!isValid())
+    if (!isSurfaceValid())
         return Uint8ClampedArray::create(rect.width() * rect.height() * 4);
     return getImageData<Unmultiplied>(rect, context(), m_surface->size());
 }
 
 PassRefPtr<Uint8ClampedArray> ImageBuffer::getPremultipliedImageData(const IntRect& rect) const
 {
-    if (!isValid())
+    if (!isSurfaceValid())
         return Uint8ClampedArray::create(rect.width() * rect.height() * 4);
     return getImageData<Premultiplied>(rect, context(), m_surface->size());
 }
 
 void ImageBuffer::putByteArray(Multiply multiplied, Uint8ClampedArray* source, const IntSize& sourceSize, const IntRect& sourceRect, const IntPoint& destPoint)
 {
-    if (!isValid())
+    if (!isSurfaceValid())
         return;
 
     ASSERT(sourceRect.width() > 0);
     ASSERT(sourceRect.height() > 0);
 
     int originX = sourceRect.x();
     int destX = destPoint.x() + sourceRect.x();
     ASSERT(destX >= 0);
     ASSERT(destX < m_surface->size().width());
     ASSERT(originX >= 0);
@@ skipping 38 matching lines @@
     }
 
     return true;
 }
 
 String ImageBuffer::toDataURL(const String& mimeType, const double* quality) const
 {
     ASSERT(MIMETypeRegistry::isSupportedImageMIMETypeForEncoding(mimeType));
 
     Vector<char> encodedImage;
-    if (!isValid() || !encodeImage(m_surface->bitmap(), mimeType, quality, &encodedImage))
+    if (!isSurfaceValid() || !encodeImage(m_surface->bitmap(), mimeType, quality, &encodedImage))
         return "data:,";
     Vector<char> base64Data;
     base64Encode(encodedImage, base64Data);
 
     return "data:" + mimeType + ";base64," + base64Data;
 }
 
 String ImageDataToDataURL(const ImageDataBuffer& imageData, const String& mimeType, const double* quality)
 {
     ASSERT(MIMETypeRegistry::isSupportedImageMIMETypeForEncoding(mimeType));
 
     Vector<char> encodedImage;
     if (!encodeImage(imageData, mimeType, quality, &encodedImage))
         return "data:,";
 
     Vector<char> base64Data;
     base64Encode(encodedImage, base64Data);
 
     return "data:" + mimeType + ";base64," + base64Data;
 }
 
 } // namespace WebCore