gecko-dev/layout/generic/nsImageFrame.h

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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/. */
/* rendering object for replaced elements with image data */
#ifndef nsImageFrame_h___
#define nsImageFrame_h___
#include "nsAtomicContainerFrame.h"
#include "nsIIOService.h"
#include "nsIObserver.h"
#include "imgINotificationObserver.h"
#include "nsDisplayList.h"
#include "imgIContainer.h"
#include "mozilla/Attributes.h"
#include "mozilla/DebugOnly.h"
#include "nsIReflowCallback.h"
#include "nsTObserverArray.h"
class nsFontMetrics;
class nsImageMap;
class nsIURI;
class nsILoadGroup;
class nsDisplayImage;
class nsPresContext;
class nsImageFrame;
class nsTransform2D;
class nsImageLoadingContent;
namespace mozilla {
class PresShell;
namespace layers {
class ImageContainer;
class ImageLayer;
class LayerManager;
} // namespace layers
} // namespace mozilla
class nsImageListener : public imgINotificationObserver
{
protected:
virtual ~nsImageListener();
public:
explicit nsImageListener(nsImageFrame *aFrame);
NS_DECL_ISUPPORTS
NS_DECL_IMGINOTIFICATIONOBSERVER
void SetFrame(nsImageFrame *frame) { mFrame = frame; }
private:
nsImageFrame *mFrame;
};
class nsImageFrame : public nsAtomicContainerFrame
, public nsIReflowCallback {
public:
template <typename T> using Maybe = mozilla::Maybe<T>;
using Nothing = mozilla::Nothing;
using Visibility = mozilla::Visibility;
typedef mozilla::image::DrawResult DrawResult;
typedef mozilla::layers::ImageContainer ImageContainer;
typedef mozilla::layers::ImageLayer ImageLayer;
typedef mozilla::layers::LayerManager LayerManager;
NS_DECL_FRAMEARENA_HELPERS
explicit nsImageFrame(nsStyleContext* aContext);
NS_DECL_QUERYFRAME_TARGET(nsImageFrame)
NS_DECL_QUERYFRAME
virtual void DestroyFrom(nsIFrame* aDestructRoot) override;
virtual void DidSetStyleContext(nsStyleContext* aOldStyleContext) override;
virtual void Init(nsIContent* aContent,
nsContainerFrame* aParent,
nsIFrame* aPrevInFlow) override;
virtual void BuildDisplayList(nsDisplayListBuilder* aBuilder,
const nsRect& aDirtyRect,
const nsDisplayListSet& aLists) override;
virtual nscoord GetMinISize(nsRenderingContext *aRenderingContext) override;
virtual nscoord GetPrefISize(nsRenderingContext *aRenderingContext) override;
virtual mozilla::IntrinsicSize GetIntrinsicSize() override;
virtual nsSize GetIntrinsicRatio() override;
virtual void Reflow(nsPresContext* aPresContext,
ReflowOutput& aDesiredSize,
const ReflowInput& aReflowInput,
nsReflowStatus& aStatus) override;
virtual nsresult GetContentForEvent(mozilla::WidgetEvent* aEvent,
nsIContent** aContent) override;
virtual nsresult HandleEvent(nsPresContext* aPresContext,
mozilla::WidgetGUIEvent* aEvent,
nsEventStatus* aEventStatus) override;
virtual nsresult GetCursor(const nsPoint& aPoint,
nsIFrame::Cursor& aCursor) override;
virtual nsresult AttributeChanged(int32_t aNameSpaceID,
nsIAtom* aAttribute,
int32_t aModType) override;
void OnVisibilityChange(Visibility aNewVisibility,
const Maybe<OnNonvisible>& aNonvisibleAction = Nothing()) override;
#ifdef ACCESSIBILITY
virtual mozilla::a11y::AccType AccessibleType() override;
#endif
virtual nsIAtom* GetType() const override;
virtual bool IsFrameOfType(uint32_t aFlags) const override
{
return nsAtomicContainerFrame::IsFrameOfType(aFlags &
~(nsIFrame::eReplaced | nsIFrame::eReplacedSizing));
}
#ifdef DEBUG_FRAME_DUMP
virtual nsresult GetFrameName(nsAString& aResult) const override;
void List(FILE* out = stderr, const char* aPrefix = "",
uint32_t aFlags = 0) const override;
#endif
nsSplittableType GetSplittableType() const override
{
return NS_FRAME_SPLITTABLE;
}
virtual LogicalSides GetLogicalSkipSides(const ReflowInput* aReflowInput = nullptr) const override;
nsresult GetIntrinsicImageSize(nsSize& aSize);
static void ReleaseGlobals() {
if (gIconLoad) {
gIconLoad->Shutdown();
NS_RELEASE(gIconLoad);
}
NS_IF_RELEASE(sIOService);
}
nsresult Notify(imgIRequest *aRequest, int32_t aType, const nsIntRect* aData);
/**
* Function to test whether aContent, which has aStyleContext as its style,
* should get an image frame. Note that this method is only used by the
* frame constructor; it's only here because it uses gIconLoad for now.
*/
static bool ShouldCreateImageFrameFor(mozilla::dom::Element* aElement,
nsStyleContext* aStyleContext);
DrawResult DisplayAltFeedback(nsRenderingContext& aRenderingContext,
const nsRect& aDirtyRect,
nsPoint aPt,
uint32_t aFlags);
nsRect GetInnerArea() const;
/**
* Return a map element associated with this image.
*/
mozilla::dom::Element* GetMapElement() const;
/**
* Return true if the image has associated image map.
*/
bool HasImageMap() const { return mImageMap || GetMapElement(); }
nsImageMap* GetImageMap();
nsImageMap* GetExistingImageMap() const { return mImageMap; }
virtual void AddInlineMinISize(nsRenderingContext *aRenderingContext,
InlineMinISizeData *aData) override;
void DisconnectMap();
// nsIReflowCallback
virtual bool ReflowFinished() override;
virtual void ReflowCallbackCanceled() override;
protected:
virtual ~nsImageFrame();
void EnsureIntrinsicSizeAndRatio();
virtual mozilla::LogicalSize
ComputeSize(nsRenderingContext *aRenderingContext,
mozilla::WritingMode aWritingMode,
const mozilla::LogicalSize& aCBSize,
nscoord aAvailableISize,
const mozilla::LogicalSize& aMargin,
const mozilla::LogicalSize& aBorder,
const mozilla::LogicalSize& aPadding,
ComputeSizeFlags aFlags) override;
bool IsServerImageMap();
void TranslateEventCoords(const nsPoint& aPoint,
nsIntPoint& aResult);
bool GetAnchorHREFTargetAndNode(nsIURI** aHref, nsString& aTarget,
nsIContent** aNode);
/**
* Computes the width of the string that fits into the available space
*
* @param in aLength total length of the string in PRUnichars
* @param in aMaxWidth width not to be exceeded
* @param out aMaxFit length of the string that fits within aMaxWidth
* in PRUnichars
* @return width of the string that fits within aMaxWidth
*/
nscoord MeasureString(const char16_t* aString,
int32_t aLength,
nscoord aMaxWidth,
uint32_t& aMaxFit,
nsRenderingContext& aContext,
nsFontMetrics& aFontMetrics);
void DisplayAltText(nsPresContext* aPresContext,
nsRenderingContext& aRenderingContext,
const nsString& aAltText,
const nsRect& aRect);
DrawResult PaintImage(nsRenderingContext& aRenderingContext, nsPoint aPt,
const nsRect& aDirtyRect, imgIContainer* aImage,
uint32_t aFlags);
/**
* If we're ready to decode - that is, if our current request's image is
* available and our decoding heuristics are satisfied - then trigger a decode
* for our image at the size we predict it will be drawn next time it's
* painted.
*/
void MaybeDecodeForPredictedSize();
protected:
friend class nsImageListener;
friend class nsImageLoadingContent;
friend class mozilla::PresShell;
nsresult OnSizeAvailable(imgIRequest* aRequest, imgIContainer* aImage);
nsresult OnFrameUpdate(imgIRequest* aRequest, const nsIntRect* aRect);
nsresult OnLoadComplete(imgIRequest* aRequest, nsresult aStatus);
/**
* Notification that aRequest will now be the current request.
*/
void NotifyNewCurrentRequest(imgIRequest *aRequest, nsresult aStatus);
/// Always sync decode our image when painting if @aForce is true.
void SetForceSyncDecoding(bool aForce) { mForceSyncDecoding = aForce; }
/**
* Computes the predicted dest rect that we'll draw into, in app units, based
* upon the provided frame content box. (The content box is what
* nsDisplayImage::GetBounds() returns.)
* The result is not necessarily contained in the frame content box.
*/
nsRect PredictedDestRect(const nsRect& aFrameContentBox);
private:
// random helpers
inline void SpecToURI(const nsAString& aSpec, nsIIOService *aIOService,
nsIURI **aURI);
inline void GetLoadGroup(nsPresContext *aPresContext,
nsILoadGroup **aLoadGroup);
nscoord GetContinuationOffset() const;
void GetDocumentCharacterSet(nsACString& aCharset) const;
bool ShouldDisplaySelection();
/**
* Recalculate mIntrinsicSize from the image.
*
* @return whether aImage's size did _not_
* match our previous intrinsic size.
*/
bool UpdateIntrinsicSize(imgIContainer* aImage);
/**
* Recalculate mIntrinsicRatio from the image.
*
* @return whether aImage's ratio did _not_
* match our previous intrinsic ratio.
*/
bool UpdateIntrinsicRatio(imgIContainer* aImage);
/**
* This function calculates the transform for converting between
* source space & destination space. May fail if our image has a
* percent-valued or zero-valued height or width.
*
* @param aTransform The transform object to populate.
*
* @return whether we succeeded in creating the transform.
*/
bool GetSourceToDestTransform(nsTransform2D& aTransform);
/**
* Helper function to check whether the request corresponds to a load we don't
* care about. Most of the decoder observer methods will bail early if this
* returns true.
*/
bool IsPendingLoad(imgIRequest* aRequest) const;
/**
* Function to convert a dirty rect in the source image to a dirty
* rect for the image frame.
*/
nsRect SourceRectToDest(const nsIntRect & aRect);
/**
* Triggers invalidation for both our image display item and, if appropriate,
* our alt-feedback display item.
*
* @param aLayerInvalidRect The area to invalidate in layer space. If null, the
* entire layer will be invalidated.
* @param aFrameInvalidRect The area to invalidate in frame space. If null, the
* entire frame will be invalidated.
*/
void InvalidateSelf(const nsIntRect* aLayerInvalidRect,
const nsRect* aFrameInvalidRect);
RefPtr<nsImageMap> mImageMap;
nsCOMPtr<imgINotificationObserver> mListener;
nsCOMPtr<imgIContainer> mImage;
nsCOMPtr<imgIContainer> mPrevImage;
nsSize mComputedSize;
mozilla::IntrinsicSize mIntrinsicSize;
nsSize mIntrinsicRatio;
bool mDisplayingIcon;
bool mFirstFrameComplete;
bool mReflowCallbackPosted;
bool mForceSyncDecoding;
static nsIIOService* sIOService;
/* loading / broken image icon support */
// XXXbz this should be handled by the prescontext, I think; that
// way we would have a single iconload per mozilla session instead
// of one per document...
// LoadIcons: initiate the loading of the static icons used to show
// loading / broken images
nsresult LoadIcons(nsPresContext *aPresContext);
nsresult LoadIcon(const nsAString& aSpec, nsPresContext *aPresContext,
imgRequestProxy **aRequest);
class IconLoad final : public nsIObserver,
public imgINotificationObserver
{
// private class that wraps the data and logic needed for
// broken image and loading image icons
public:
IconLoad();
void Shutdown();
NS_DECL_ISUPPORTS
NS_DECL_NSIOBSERVER
NS_DECL_IMGINOTIFICATIONOBSERVER
void AddIconObserver(nsImageFrame *frame) {
MOZ_ASSERT(!mIconObservers.Contains(frame),
"Observer shouldn't aleady be in array");
mIconObservers.AppendElement(frame);
}
void RemoveIconObserver(nsImageFrame *frame) {
mozilla::DebugOnly<bool> didRemove = mIconObservers.RemoveElement(frame);
MOZ_ASSERT(didRemove, "Observer not in array");
}
private:
~IconLoad() {}
void GetPrefs();
nsTObserverArray<nsImageFrame*> mIconObservers;
public:
RefPtr<imgRequestProxy> mLoadingImage;
RefPtr<imgRequestProxy> mBrokenImage;
bool mPrefForceInlineAltText;
bool mPrefShowPlaceholders;
bool mPrefShowLoadingPlaceholder;
};
public:
static IconLoad* gIconLoad; // singleton pattern: one LoadIcons instance is used
friend class nsDisplayImage;
};
/**
* Note that nsDisplayImage does not receive events. However, an image element
* is replaced content so its background will be z-adjacent to the
* image itself, and hence receive events just as if the image itself
* received events.
*/
class nsDisplayImage : public nsDisplayImageContainer {
public:
typedef mozilla::layers::LayerManager LayerManager;
nsDisplayImage(nsDisplayListBuilder* aBuilder, nsImageFrame* aFrame,
imgIContainer* aImage, imgIContainer* aPrevImage)
: nsDisplayImageContainer(aBuilder, aFrame)
, mImage(aImage)
, mPrevImage(aPrevImage)
{
MOZ_COUNT_CTOR(nsDisplayImage);
}
virtual ~nsDisplayImage() {
MOZ_COUNT_DTOR(nsDisplayImage);
}
virtual nsDisplayItemGeometry* AllocateGeometry(nsDisplayListBuilder* aBuilder) override;
virtual void ComputeInvalidationRegion(nsDisplayListBuilder* aBuilder,
const nsDisplayItemGeometry* aGeometry,
nsRegion* aInvalidRegion) override;
virtual void Paint(nsDisplayListBuilder* aBuilder,
nsRenderingContext* aCtx) override;
virtual already_AddRefed<imgIContainer> GetImage() override;
/**
* @return The dest rect we'll use when drawing this image, in app units.
* Not necessarily contained in this item's bounds.
*/
virtual nsRect GetDestRect() override;
virtual LayerState GetLayerState(nsDisplayListBuilder* aBuilder,
LayerManager* aManager,
const ContainerLayerParameters& aParameters) override;
nsRect GetBounds(bool* aSnap)
{
*aSnap = true;
nsImageFrame* imageFrame = static_cast<nsImageFrame*>(mFrame);
return imageFrame->GetInnerArea() + ToReferenceFrame();
}
virtual nsRect GetBounds(nsDisplayListBuilder* aBuilder,
bool* aSnap) override
{
return GetBounds(aSnap);
}
virtual nsRegion GetOpaqueRegion(nsDisplayListBuilder* aBuilder,
bool* aSnap) override;
virtual already_AddRefed<Layer> BuildLayer(nsDisplayListBuilder* aBuilder,
LayerManager* aManager,
const ContainerLayerParameters& aContainerParameters) override;
NS_DISPLAY_DECL_NAME("Image", TYPE_IMAGE)
private:
nsCOMPtr<imgIContainer> mImage;
nsCOMPtr<imgIContainer> mPrevImage;
};
#endif /* nsImageFrame_h___ */