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diff --git a/image/ClippedImage.cpp b/image/ClippedImage.cpp
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+++ b/image/ClippedImage.cpp
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+/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* 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 http://mozilla.org/MPL/2.0/. */
+
+#include "ClippedImage.h"
+
+#include <algorithm>
+#include <new> // Workaround for bug in VS10; see bug 981264.
+#include <cmath>
+#include <utility>
+
+#include "gfxDrawable.h"
+#include "gfxPlatform.h"
+#include "gfxUtils.h"
+#include "mozilla/gfx/2D.h"
+#include "mozilla/Move.h"
+#include "mozilla/RefPtr.h"
+#include "mozilla/Pair.h"
+#include "mozilla/Tuple.h"
+
+#include "ImageRegion.h"
+#include "Orientation.h"
+#include "SVGImageContext.h"
+
+namespace mozilla {
+
+using namespace gfx;
+using layers::LayerManager;
+using layers::ImageContainer;
+using std::make_pair;
+using std::max;
+using std::modf;
+using std::pair;
+
+namespace image {
+
+class ClippedImageCachedSurface
+{
+public:
+ ClippedImageCachedSurface(already_AddRefed<SourceSurface> aSurface,
+ const nsIntSize& aSize,
+ const Maybe<SVGImageContext>& aSVGContext,
+ float aFrame,
+ uint32_t aFlags,
+ DrawResult aDrawResult)
+ : mSurface(aSurface)
+ , mSize(aSize)
+ , mSVGContext(aSVGContext)
+ , mFrame(aFrame)
+ , mFlags(aFlags)
+ , mDrawResult(aDrawResult)
+ {
+ MOZ_ASSERT(mSurface, "Must have a valid surface");
+ }
+
+ bool Matches(const nsIntSize& aSize,
+ const Maybe<SVGImageContext>& aSVGContext,
+ float aFrame,
+ uint32_t aFlags) const
+ {
+ return mSize == aSize &&
+ mSVGContext == aSVGContext &&
+ mFrame == aFrame &&
+ mFlags == aFlags;
+ }
+
+ already_AddRefed<SourceSurface> Surface() const
+ {
+ RefPtr<SourceSurface> surf(mSurface);
+ return surf.forget();
+ }
+
+ DrawResult GetDrawResult() const
+ {
+ return mDrawResult;
+ }
+
+ bool NeedsRedraw() const
+ {
+ return mDrawResult != DrawResult::SUCCESS &&
+ mDrawResult != DrawResult::BAD_IMAGE;
+ }
+
+private:
+ RefPtr<SourceSurface> mSurface;
+ const nsIntSize mSize;
+ Maybe<SVGImageContext> mSVGContext;
+ const float mFrame;
+ const uint32_t mFlags;
+ const DrawResult mDrawResult;
+};
+
+class DrawSingleTileCallback : public gfxDrawingCallback
+{
+public:
+ DrawSingleTileCallback(ClippedImage* aImage,
+ const nsIntSize& aSize,
+ const Maybe<SVGImageContext>& aSVGContext,
+ uint32_t aWhichFrame,
+ uint32_t aFlags)
+ : mImage(aImage)
+ , mSize(aSize)
+ , mSVGContext(aSVGContext)
+ , mWhichFrame(aWhichFrame)
+ , mFlags(aFlags)
+ , mDrawResult(DrawResult::NOT_READY)
+ {
+ MOZ_ASSERT(mImage, "Must have an image to clip");
+ }
+
+ virtual bool operator()(gfxContext* aContext,
+ const gfxRect& aFillRect,
+ const SamplingFilter aSamplingFilter,
+ const gfxMatrix& aTransform)
+ {
+ MOZ_ASSERT(aTransform.IsIdentity(),
+ "Caller is probably CreateSamplingRestrictedDrawable, "
+ "which should not happen");
+
+ // Draw the image. |gfxCallbackDrawable| always calls this function with
+ // arguments that guarantee we never tile.
+ mDrawResult =
+ mImage->DrawSingleTile(aContext, mSize, ImageRegion::Create(aFillRect),
+ mWhichFrame, aSamplingFilter, mSVGContext, mFlags);
+
+ return true;
+ }
+
+ DrawResult GetDrawResult() { return mDrawResult; }
+
+private:
+ RefPtr<ClippedImage> mImage;
+ const nsIntSize mSize;
+ const Maybe<SVGImageContext>& mSVGContext;
+ const uint32_t mWhichFrame;
+ const uint32_t mFlags;
+ DrawResult mDrawResult;
+};
+
+ClippedImage::ClippedImage(Image* aImage,
+ nsIntRect aClip,
+ const Maybe<nsSize>& aSVGViewportSize)
+ : ImageWrapper(aImage)
+ , mClip(aClip)
+{
+ MOZ_ASSERT(aImage != nullptr, "ClippedImage requires an existing Image");
+ MOZ_ASSERT_IF(aSVGViewportSize,
+ aImage->GetType() == imgIContainer::TYPE_VECTOR);
+ if (aSVGViewportSize) {
+ mSVGViewportSize = Some(aSVGViewportSize->ToNearestPixels(
+ nsPresContext::AppUnitsPerCSSPixel()));
+ }
+}
+
+ClippedImage::~ClippedImage()
+{ }
+
+bool
+ClippedImage::ShouldClip()
+{
+ // We need to evaluate the clipping region against the image's width and
+ // height once they're available to determine if it's valid and whether we
+ // actually need to do any work. We may fail if the image's width and height
+ // aren't available yet, in which case we'll try again later.
+ if (mShouldClip.isNothing()) {
+ int32_t width, height;
+ RefPtr<ProgressTracker> progressTracker =
+ InnerImage()->GetProgressTracker();
+ if (InnerImage()->HasError()) {
+ // If there's a problem with the inner image we'll let it handle
+ // everything.
+ mShouldClip.emplace(false);
+ } else if (mSVGViewportSize && !mSVGViewportSize->IsEmpty()) {
+ // Clamp the clipping region to the size of the SVG viewport.
+ nsIntRect svgViewportRect(nsIntPoint(0,0), *mSVGViewportSize);
+
+ mClip = mClip.Intersect(svgViewportRect);
+
+ // If the clipping region is the same size as the SVG viewport size
+ // we don't have to do anything.
+ mShouldClip.emplace(!mClip.IsEqualInterior(svgViewportRect));
+ } else if (NS_SUCCEEDED(InnerImage()->GetWidth(&width)) && width > 0 &&
+ NS_SUCCEEDED(InnerImage()->GetHeight(&height)) && height > 0) {
+ // Clamp the clipping region to the size of the underlying image.
+ mClip = mClip.Intersect(nsIntRect(0, 0, width, height));
+
+ // If the clipping region is the same size as the underlying image we
+ // don't have to do anything.
+ mShouldClip.emplace(!mClip.IsEqualInterior(nsIntRect(0, 0, width,
+ height)));
+ } else if (progressTracker &&
+ !(progressTracker->GetProgress() & FLAG_LOAD_COMPLETE)) {
+ // The image just hasn't finished loading yet. We don't yet know whether
+ // clipping with be needed or not for now. Just return without memorizing
+ // anything.
+ return false;
+ } else {
+ // We have a fully loaded image without a clearly defined width and
+ // height. This can happen with SVG images.
+ mShouldClip.emplace(false);
+ }
+ }
+
+ MOZ_ASSERT(mShouldClip.isSome(), "Should have computed a result");
+ return *mShouldClip;
+}
+
+NS_IMPL_ISUPPORTS_INHERITED0(ClippedImage, ImageWrapper)
+
+NS_IMETHODIMP
+ClippedImage::GetWidth(int32_t* aWidth)
+{
+ if (!ShouldClip()) {
+ return InnerImage()->GetWidth(aWidth);
+ }
+
+ *aWidth = mClip.width;
+ return NS_OK;
+}
+
+NS_IMETHODIMP
+ClippedImage::GetHeight(int32_t* aHeight)
+{
+ if (!ShouldClip()) {
+ return InnerImage()->GetHeight(aHeight);
+ }
+
+ *aHeight = mClip.height;
+ return NS_OK;
+}
+
+NS_IMETHODIMP
+ClippedImage::GetIntrinsicSize(nsSize* aSize)
+{
+ if (!ShouldClip()) {
+ return InnerImage()->GetIntrinsicSize(aSize);
+ }
+
+ *aSize = nsSize(mClip.width, mClip.height);
+ return NS_OK;
+}
+
+NS_IMETHODIMP
+ClippedImage::GetIntrinsicRatio(nsSize* aRatio)
+{
+ if (!ShouldClip()) {
+ return InnerImage()->GetIntrinsicRatio(aRatio);
+ }
+
+ *aRatio = nsSize(mClip.width, mClip.height);
+ return NS_OK;
+}
+
+NS_IMETHODIMP_(already_AddRefed<SourceSurface>)
+ClippedImage::GetFrame(uint32_t aWhichFrame,
+ uint32_t aFlags)
+{
+ DrawResult result;
+ RefPtr<SourceSurface> surface;
+ Tie(result, surface) = GetFrameInternal(mClip.Size(), Nothing(), aWhichFrame, aFlags);
+ return surface.forget();
+}
+
+NS_IMETHODIMP_(already_AddRefed<SourceSurface>)
+ClippedImage::GetFrameAtSize(const IntSize& aSize,
+ uint32_t aWhichFrame,
+ uint32_t aFlags)
+{
+ // XXX(seth): It'd be nice to support downscale-during-decode for this case,
+ // but right now we just fall back to the intrinsic size.
+ return GetFrame(aWhichFrame, aFlags);
+}
+
+Pair<DrawResult, RefPtr<SourceSurface>>
+ClippedImage::GetFrameInternal(const nsIntSize& aSize,
+ const Maybe<SVGImageContext>& aSVGContext,
+ uint32_t aWhichFrame,
+ uint32_t aFlags)
+{
+ if (!ShouldClip()) {
+ RefPtr<SourceSurface> surface = InnerImage()->GetFrame(aWhichFrame, aFlags);
+ return MakePair(surface ? DrawResult::SUCCESS : DrawResult::NOT_READY,
+ Move(surface));
+ }
+
+ float frameToDraw = InnerImage()->GetFrameIndex(aWhichFrame);
+ if (!mCachedSurface ||
+ !mCachedSurface->Matches(aSize, aSVGContext, frameToDraw, aFlags) ||
+ mCachedSurface->NeedsRedraw()) {
+ // Create a surface to draw into.
+ RefPtr<DrawTarget> target = gfxPlatform::GetPlatform()->
+ CreateOffscreenContentDrawTarget(IntSize(aSize.width, aSize.height),
+ SurfaceFormat::B8G8R8A8);
+ if (!target || !target->IsValid()) {
+ NS_ERROR("Could not create a DrawTarget");
+ return MakePair(DrawResult::TEMPORARY_ERROR, RefPtr<SourceSurface>());
+ }
+
+ RefPtr<gfxContext> ctx = gfxContext::CreateOrNull(target);
+ MOZ_ASSERT(ctx); // already checked the draw target above
+
+ // Create our callback.
+ RefPtr<DrawSingleTileCallback> drawTileCallback =
+ new DrawSingleTileCallback(this, aSize, aSVGContext, aWhichFrame, aFlags);
+ RefPtr<gfxDrawable> drawable =
+ new gfxCallbackDrawable(drawTileCallback, aSize);
+
+ // Actually draw. The callback will end up invoking DrawSingleTile.
+ gfxUtils::DrawPixelSnapped(ctx, drawable, aSize,
+ ImageRegion::Create(aSize),
+ SurfaceFormat::B8G8R8A8,
+ SamplingFilter::LINEAR,
+ imgIContainer::FLAG_CLAMP);
+
+ // Cache the resulting surface.
+ mCachedSurface =
+ MakeUnique<ClippedImageCachedSurface>(target->Snapshot(), aSize, aSVGContext,
+ frameToDraw, aFlags,
+ drawTileCallback->GetDrawResult());
+ }
+
+ MOZ_ASSERT(mCachedSurface, "Should have a cached surface now");
+ RefPtr<SourceSurface> surface = mCachedSurface->Surface();
+ return MakePair(mCachedSurface->GetDrawResult(), Move(surface));
+}
+
+NS_IMETHODIMP_(bool)
+ClippedImage::IsImageContainerAvailable(LayerManager* aManager, uint32_t aFlags)
+{
+ if (!ShouldClip()) {
+ return InnerImage()->IsImageContainerAvailable(aManager, aFlags);
+ }
+ return false;
+}
+
+NS_IMETHODIMP_(already_AddRefed<ImageContainer>)
+ClippedImage::GetImageContainer(LayerManager* aManager, uint32_t aFlags)
+{
+ // XXX(seth): We currently don't have a way of clipping the result of
+ // GetImageContainer. We work around this by always returning null, but if it
+ // ever turns out that ClippedImage is widely used on codepaths that can
+ // actually benefit from GetImageContainer, it would be a good idea to fix
+ // that method for performance reasons.
+
+ if (!ShouldClip()) {
+ return InnerImage()->GetImageContainer(aManager, aFlags);
+ }
+
+ return nullptr;
+}
+
+static bool
+MustCreateSurface(gfxContext* aContext,
+ const nsIntSize& aSize,
+ const ImageRegion& aRegion,
+ const uint32_t aFlags)
+{
+ gfxRect imageRect(0, 0, aSize.width, aSize.height);
+ bool willTile = !imageRect.Contains(aRegion.Rect()) &&
+ !(aFlags & imgIContainer::FLAG_CLAMP);
+ bool willResample = aContext->CurrentMatrix().HasNonIntegerTranslation() &&
+ (willTile || !aRegion.RestrictionContains(imageRect));
+ return willTile || willResample;
+}
+
+NS_IMETHODIMP_(DrawResult)
+ClippedImage::Draw(gfxContext* aContext,
+ const nsIntSize& aSize,
+ const ImageRegion& aRegion,
+ uint32_t aWhichFrame,
+ SamplingFilter aSamplingFilter,
+ const Maybe<SVGImageContext>& aSVGContext,
+ uint32_t aFlags)
+{
+ if (!ShouldClip()) {
+ return InnerImage()->Draw(aContext, aSize, aRegion, aWhichFrame,
+ aSamplingFilter, aSVGContext, aFlags);
+ }
+
+ // Check for tiling. If we need to tile then we need to create a
+ // gfxCallbackDrawable to handle drawing for us.
+ if (MustCreateSurface(aContext, aSize, aRegion, aFlags)) {
+ // Create a temporary surface containing a single tile of this image.
+ // GetFrame will call DrawSingleTile internally.
+ DrawResult result;
+ RefPtr<SourceSurface> surface;
+ Tie(result, surface) =
+ GetFrameInternal(aSize, aSVGContext, aWhichFrame, aFlags);
+ if (!surface) {
+ MOZ_ASSERT(result != DrawResult::SUCCESS);
+ return result;
+ }
+
+ // Create a drawable from that surface.
+ RefPtr<gfxSurfaceDrawable> drawable =
+ new gfxSurfaceDrawable(surface, aSize);
+
+ // Draw.
+ gfxUtils::DrawPixelSnapped(aContext, drawable, aSize, aRegion,
+ SurfaceFormat::B8G8R8A8, aSamplingFilter);
+
+ return result;
+ }
+
+ return DrawSingleTile(aContext, aSize, aRegion, aWhichFrame,
+ aSamplingFilter, aSVGContext, aFlags);
+}
+
+DrawResult
+ClippedImage::DrawSingleTile(gfxContext* aContext,
+ const nsIntSize& aSize,
+ const ImageRegion& aRegion,
+ uint32_t aWhichFrame,
+ SamplingFilter aSamplingFilter,
+ const Maybe<SVGImageContext>& aSVGContext,
+ uint32_t aFlags)
+{
+ MOZ_ASSERT(!MustCreateSurface(aContext, aSize, aRegion, aFlags),
+ "Shouldn't need to create a surface");
+
+ gfxRect clip(mClip.x, mClip.y, mClip.width, mClip.height);
+ nsIntSize size(aSize), innerSize(aSize);
+ bool needScale = false;
+ if (mSVGViewportSize && !mSVGViewportSize->IsEmpty()) {
+ innerSize = *mSVGViewportSize;
+ needScale = true;
+ } else if (NS_SUCCEEDED(InnerImage()->GetWidth(&innerSize.width)) &&
+ NS_SUCCEEDED(InnerImage()->GetHeight(&innerSize.height))) {
+ needScale = true;
+ } else {
+ MOZ_ASSERT_UNREACHABLE(
+ "If ShouldClip() led us to draw then we should never get here");
+ }
+
+ if (needScale) {
+ double scaleX = aSize.width / clip.width;
+ double scaleY = aSize.height / clip.height;
+
+ // Map the clip and size to the scale requested by the caller.
+ clip.Scale(scaleX, scaleY);
+ size = innerSize;
+ size.Scale(scaleX, scaleY);
+ }
+
+ // We restrict our drawing to only the clipping region, and translate so that
+ // the clipping region is placed at the position the caller expects.
+ ImageRegion region(aRegion);
+ region.MoveBy(clip.x, clip.y);
+ region = region.Intersect(clip);
+
+ gfxContextMatrixAutoSaveRestore saveMatrix(aContext);
+ aContext->Multiply(gfxMatrix::Translation(-clip.x, -clip.y));
+
+ auto unclipViewport = [&](const SVGImageContext& aOldContext) {
+ // Map the viewport to the inner image. Note that we don't take the aSize
+ // parameter of imgIContainer::Draw into account, just the clipping region.
+ // The size in pixels at which the output will ultimately be drawn is
+ // irrelevant here since the purpose of the SVG viewport size is to
+ // determine what *region* of the SVG document will be drawn.
+ CSSIntSize vSize(aOldContext.GetViewportSize());
+ vSize.width = ceil(vSize.width * double(innerSize.width) / mClip.width);
+ vSize.height =
+ ceil(vSize.height * double(innerSize.height) / mClip.height);
+
+ return SVGImageContext(vSize,
+ aOldContext.GetPreserveAspectRatio());
+ };
+
+ return InnerImage()->Draw(aContext, size, region,
+ aWhichFrame, aSamplingFilter,
+ aSVGContext.map(unclipViewport),
+ aFlags);
+}
+
+NS_IMETHODIMP
+ClippedImage::RequestDiscard()
+{
+ // We're very aggressive about discarding.
+ mCachedSurface = nullptr;
+
+ return InnerImage()->RequestDiscard();
+}
+
+NS_IMETHODIMP_(Orientation)
+ClippedImage::GetOrientation()
+{
+ // XXX(seth): This should not actually be here; this is just to work around a
+ // what appears to be a bug in MSVC's linker.
+ return InnerImage()->GetOrientation();
+}
+
+nsIntSize
+ClippedImage::OptimalImageSizeForDest(const gfxSize& aDest,
+ uint32_t aWhichFrame,
+ SamplingFilter aSamplingFilter,
+ uint32_t aFlags)
+{
+ if (!ShouldClip()) {
+ return InnerImage()->OptimalImageSizeForDest(aDest, aWhichFrame,
+ aSamplingFilter, aFlags);
+ }
+
+ int32_t imgWidth, imgHeight;
+ bool needScale = false;
+ bool forceUniformScaling = false;
+ if (mSVGViewportSize && !mSVGViewportSize->IsEmpty()) {
+ imgWidth = mSVGViewportSize->width;
+ imgHeight = mSVGViewportSize->height;
+ needScale = true;
+ forceUniformScaling = (aFlags & imgIContainer::FLAG_FORCE_UNIFORM_SCALING);
+ } else if (NS_SUCCEEDED(InnerImage()->GetWidth(&imgWidth)) &&
+ NS_SUCCEEDED(InnerImage()->GetHeight(&imgHeight))) {
+ needScale = true;
+ }
+
+ if (needScale) {
+ // To avoid ugly sampling artifacts, ClippedImage needs the image size to
+ // be chosen such that the clipping region lies on pixel boundaries.
+
+ // First, we select a scale that's good for ClippedImage. An integer
+ // multiple of the size of the clipping region is always fine.
+ IntSize scale = IntSize::Ceil(aDest.width / mClip.width,
+ aDest.height / mClip.height);
+
+ if (forceUniformScaling) {
+ scale.width = scale.height = max(scale.height, scale.width);
+ }
+
+ // Determine the size we'd prefer to render the inner image at, and ask the
+ // inner image what size we should actually use.
+ gfxSize desiredSize(imgWidth * scale.width, imgHeight * scale.height);
+ nsIntSize innerDesiredSize =
+ InnerImage()->OptimalImageSizeForDest(desiredSize, aWhichFrame,
+ aSamplingFilter, aFlags);
+
+ // To get our final result, we take the inner image's desired size and
+ // determine how large the clipped region would be at that scale. (Again, we
+ // ensure an integer multiple of the size of the clipping region.)
+ IntSize finalScale = IntSize::Ceil(double(innerDesiredSize.width) / imgWidth,
+ double(innerDesiredSize.height) / imgHeight);
+ return mClip.Size() * finalScale;
+ }
+
+ MOZ_ASSERT(false,
+ "If ShouldClip() led us to draw then we should never get here");
+ return InnerImage()->OptimalImageSizeForDest(aDest, aWhichFrame,
+ aSamplingFilter, aFlags);
+}
+
+NS_IMETHODIMP_(nsIntRect)
+ClippedImage::GetImageSpaceInvalidationRect(const nsIntRect& aRect)
+{
+ if (!ShouldClip()) {
+ return InnerImage()->GetImageSpaceInvalidationRect(aRect);
+ }
+
+ nsIntRect rect(InnerImage()->GetImageSpaceInvalidationRect(aRect));
+ rect = rect.Intersect(mClip);
+ rect.MoveBy(-mClip.x, -mClip.y);
+ return rect;
+}
+
+} // namespace image
+} // namespace mozilla