1.1 --- /dev/null Thu Jan 01 00:00:00 1970 +0000
1.2 +++ b/layout/svg/nsSVGEffects.h Wed Dec 31 06:09:35 2014 +0100
1.3 @@ -0,0 +1,475 @@
1.4 +/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
1.5 +/* This Source Code Form is subject to the terms of the Mozilla Public
1.6 + * License, v. 2.0. If a copy of the MPL was not distributed with this
1.7 + * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
1.8 +
1.9 +#ifndef NSSVGEFFECTS_H_
1.10 +#define NSSVGEFFECTS_H_
1.11 +
1.12 +#include "mozilla/Attributes.h"
1.13 +#include "FramePropertyTable.h"
1.14 +#include "mozilla/dom/Element.h"
1.15 +#include "nsHashKeys.h"
1.16 +#include "nsID.h"
1.17 +#include "nsIFrame.h"
1.18 +#include "nsIMutationObserver.h"
1.19 +#include "nsInterfaceHashtable.h"
1.20 +#include "nsISupportsBase.h"
1.21 +#include "nsISupportsImpl.h"
1.22 +#include "nsReferencedElement.h"
1.23 +#include "nsStubMutationObserver.h"
1.24 +#include "nsSVGUtils.h"
1.25 +#include "nsTHashtable.h"
1.26 +#include "nsURIHashKey.h"
1.27 +
1.28 +class nsIAtom;
1.29 +class nsIPresShell;
1.30 +class nsIURI;
1.31 +class nsSVGClipPathFrame;
1.32 +class nsSVGPaintServerFrame;
1.33 +class nsSVGFilterFrame;
1.34 +class nsSVGMaskFrame;
1.35 +
1.36 +/*
1.37 + * This interface allows us to be notified when a piece of SVG content is
1.38 + * re-rendered.
1.39 + *
1.40 + * Concrete implementations of this interface need to implement
1.41 + * "GetTarget()" to specify the piece of SVG content that they'd like to
1.42 + * monitor, and they need to implement "DoUpdate" to specify how we'll react
1.43 + * when that content gets re-rendered. They also need to implement a
1.44 + * constructor and destructor, which should call StartListening and
1.45 + * StopListening, respectively.
1.46 + */
1.47 +class nsSVGRenderingObserver : public nsStubMutationObserver {
1.48 +public:
1.49 + typedef mozilla::dom::Element Element;
1.50 + nsSVGRenderingObserver()
1.51 + : mInObserverList(false)
1.52 + {}
1.53 + virtual ~nsSVGRenderingObserver()
1.54 + {}
1.55 +
1.56 + // nsISupports
1.57 + NS_DECL_ISUPPORTS
1.58 +
1.59 + // nsIMutationObserver
1.60 + NS_DECL_NSIMUTATIONOBSERVER_ATTRIBUTECHANGED
1.61 + NS_DECL_NSIMUTATIONOBSERVER_CONTENTAPPENDED
1.62 + NS_DECL_NSIMUTATIONOBSERVER_CONTENTINSERTED
1.63 + NS_DECL_NSIMUTATIONOBSERVER_CONTENTREMOVED
1.64 +
1.65 + void InvalidateViaReferencedElement();
1.66 +
1.67 + // When a nsSVGRenderingObserver list gets forcibly cleared, it uses this
1.68 + // callback to notify every observer that's cleared from it, so they can
1.69 + // react.
1.70 + void NotifyEvictedFromRenderingObserverList();
1.71 +
1.72 + bool IsInObserverList() const { return mInObserverList; }
1.73 +
1.74 + nsIFrame* GetReferencedFrame();
1.75 + /**
1.76 + * @param aOK this is only for the convenience of callers. We set *aOK to false
1.77 + * if the frame is the wrong type
1.78 + */
1.79 + nsIFrame* GetReferencedFrame(nsIAtom* aFrameType, bool* aOK);
1.80 +
1.81 + Element* GetReferencedElement();
1.82 +
1.83 + virtual bool ObservesReflow() { return true; }
1.84 +
1.85 +protected:
1.86 + // Non-virtual protected methods
1.87 + void StartListening();
1.88 + void StopListening();
1.89 +
1.90 + // Virtual protected methods
1.91 + virtual void DoUpdate() = 0; // called when the referenced resource changes.
1.92 +
1.93 + // This is an internally-used version of GetReferencedElement that doesn't
1.94 + // forcibly add us as an observer. (whereas GetReferencedElement does)
1.95 + virtual Element* GetTarget() = 0;
1.96 +
1.97 + // Whether we're in our referenced element's observer list at this time.
1.98 + bool mInObserverList;
1.99 +};
1.100 +
1.101 +
1.102 +/*
1.103 + * SVG elements reference supporting resources by element ID. We need to
1.104 + * track when those resources change and when the DOM changes in ways
1.105 + * that affect which element is referenced by a given ID (e.g., when
1.106 + * element IDs change). The code here is responsible for that.
1.107 + *
1.108 + * When a frame references a supporting resource, we create a property
1.109 + * object derived from nsSVGIDRenderingObserver to manage the relationship. The
1.110 + * property object is attached to the referencing frame.
1.111 + */
1.112 +class nsSVGIDRenderingObserver : public nsSVGRenderingObserver {
1.113 +public:
1.114 + typedef mozilla::dom::Element Element;
1.115 + nsSVGIDRenderingObserver(nsIURI* aURI, nsIFrame *aFrame,
1.116 + bool aReferenceImage);
1.117 + virtual ~nsSVGIDRenderingObserver();
1.118 +
1.119 +protected:
1.120 + Element* GetTarget() MOZ_OVERRIDE { return mElement.get(); }
1.121 +
1.122 + // This is called when the referenced resource changes.
1.123 + virtual void DoUpdate() MOZ_OVERRIDE;
1.124 +
1.125 + class SourceReference : public nsReferencedElement {
1.126 + public:
1.127 + SourceReference(nsSVGIDRenderingObserver* aContainer) : mContainer(aContainer) {}
1.128 + protected:
1.129 + virtual void ElementChanged(Element* aFrom, Element* aTo) MOZ_OVERRIDE {
1.130 + mContainer->StopListening();
1.131 + nsReferencedElement::ElementChanged(aFrom, aTo);
1.132 + mContainer->StartListening();
1.133 + mContainer->DoUpdate();
1.134 + }
1.135 + /**
1.136 + * Override IsPersistent because we want to keep tracking the element
1.137 + * for the ID even when it changes.
1.138 + */
1.139 + virtual bool IsPersistent() MOZ_OVERRIDE { return true; }
1.140 + private:
1.141 + nsSVGIDRenderingObserver* mContainer;
1.142 + };
1.143 +
1.144 + SourceReference mElement;
1.145 + // The frame that this property is attached to
1.146 + nsIFrame *mFrame;
1.147 + // When a presshell is torn down, we don't delete the properties for
1.148 + // each frame until after the frames are destroyed. So here we remember
1.149 + // the presshell for the frames we care about and, before we use the frame,
1.150 + // we test the presshell to see if it's destroying itself. If it is,
1.151 + // then the frame pointer is not valid and we know the frame has gone away.
1.152 + nsIPresShell *mFramePresShell;
1.153 +};
1.154 +
1.155 +/**
1.156 + * In a filter chain, there can be multiple SVG reference filters.
1.157 + * e.g. filter: url(#svg-filter-1) blur(10px) url(#svg-filter-2);
1.158 + *
1.159 + * This class keeps track of one SVG reference filter in a filter chain.
1.160 + * e.g. url(#svg-filter-1)
1.161 + *
1.162 + * It fires invalidations when the SVG filter element's id changes or when
1.163 + * the SVG filter element's content changes.
1.164 + *
1.165 + * The nsSVGFilterProperty class manages a list of nsSVGFilterReferences.
1.166 + */
1.167 +class nsSVGFilterReference :
1.168 + public nsSVGIDRenderingObserver, public nsISVGFilterReference {
1.169 +public:
1.170 + nsSVGFilterReference(nsIURI *aURI, nsIFrame *aFilteredFrame)
1.171 + : nsSVGIDRenderingObserver(aURI, aFilteredFrame, false) {}
1.172 +
1.173 + bool ReferencesValidResource() { return GetFilterFrame(); }
1.174 +
1.175 + /**
1.176 + * @return the filter frame, or null if there is no filter frame
1.177 + */
1.178 + nsSVGFilterFrame *GetFilterFrame();
1.179 +
1.180 + // nsISupports
1.181 + NS_DECL_ISUPPORTS
1.182 +
1.183 + // nsISVGFilterReference
1.184 + virtual void Invalidate() MOZ_OVERRIDE { DoUpdate(); };
1.185 +
1.186 +private:
1.187 + // nsSVGIDRenderingObserver
1.188 + virtual void DoUpdate() MOZ_OVERRIDE;
1.189 +};
1.190 +
1.191 +/**
1.192 + * This class manages a list of nsSVGFilterReferences, which represent SVG
1.193 + * reference filters in a filter chain.
1.194 + * e.g. filter: url(#svg-filter-1) blur(10px) url(#svg-filter-2);
1.195 + *
1.196 + * In the above example, the nsSVGFilterProperty will manage two
1.197 + * nsSVGFilterReferences, one for each SVG reference filter. CSS filters like
1.198 + * "blur(10px)" don't reference filter elements, so they don't need an
1.199 + * nsSVGFilterReference. The style system invalidates changes to CSS filters.
1.200 + */
1.201 +class nsSVGFilterProperty : public nsISupports {
1.202 +public:
1.203 + nsSVGFilterProperty(const nsTArray<nsStyleFilter> &aFilters,
1.204 + nsIFrame *aFilteredFrame);
1.205 + virtual ~nsSVGFilterProperty();
1.206 +
1.207 + const nsTArray<nsStyleFilter>& GetFilters() { return mFilters; }
1.208 + bool ReferencesValidResources();
1.209 + bool IsInObserverLists() const;
1.210 + void Invalidate();
1.211 +
1.212 + // nsISupports
1.213 + NS_DECL_ISUPPORTS
1.214 +
1.215 +private:
1.216 + nsTArray<nsSVGFilterReference*> mReferences;
1.217 + nsTArray<nsStyleFilter> mFilters;
1.218 +};
1.219 +
1.220 +class nsSVGMarkerProperty : public nsSVGIDRenderingObserver {
1.221 +public:
1.222 + nsSVGMarkerProperty(nsIURI *aURI, nsIFrame *aFrame, bool aReferenceImage)
1.223 + : nsSVGIDRenderingObserver(aURI, aFrame, aReferenceImage) {}
1.224 +
1.225 +protected:
1.226 + virtual void DoUpdate() MOZ_OVERRIDE;
1.227 +};
1.228 +
1.229 +class nsSVGTextPathProperty : public nsSVGIDRenderingObserver {
1.230 +public:
1.231 + nsSVGTextPathProperty(nsIURI *aURI, nsIFrame *aFrame, bool aReferenceImage)
1.232 + : nsSVGIDRenderingObserver(aURI, aFrame, aReferenceImage)
1.233 + , mValid(true) {}
1.234 +
1.235 + virtual bool ObservesReflow() MOZ_OVERRIDE { return false; }
1.236 +
1.237 +protected:
1.238 + virtual void DoUpdate() MOZ_OVERRIDE;
1.239 +
1.240 +private:
1.241 + /**
1.242 + * Returns true if the target of the textPath is the frame of a 'path' element.
1.243 + */
1.244 + bool TargetIsValid();
1.245 +
1.246 + bool mValid;
1.247 +};
1.248 +
1.249 +class nsSVGPaintingProperty : public nsSVGIDRenderingObserver {
1.250 +public:
1.251 + nsSVGPaintingProperty(nsIURI *aURI, nsIFrame *aFrame, bool aReferenceImage)
1.252 + : nsSVGIDRenderingObserver(aURI, aFrame, aReferenceImage) {}
1.253 +
1.254 +protected:
1.255 + virtual void DoUpdate() MOZ_OVERRIDE;
1.256 +};
1.257 +
1.258 +/**
1.259 + * A manager for one-shot nsSVGRenderingObserver tracking.
1.260 + * nsSVGRenderingObservers can be added or removed. They are not strongly
1.261 + * referenced so an observer must be removed before it dies.
1.262 + * When InvalidateAll is called, all outstanding references get
1.263 + * InvalidateViaReferencedElement()
1.264 + * called on them and the list is cleared. The intent is that
1.265 + * the observer will force repainting of whatever part of the document
1.266 + * is needed, and then at paint time the observer will do a clean lookup
1.267 + * of the referenced element and [re-]add itself to the element's observer list.
1.268 + *
1.269 + * InvalidateAll must be called before this object is destroyed, i.e.
1.270 + * before the referenced frame is destroyed. This should normally happen
1.271 + * via nsSVGContainerFrame::RemoveFrame, since only frames in the frame
1.272 + * tree should be referenced.
1.273 + */
1.274 +class nsSVGRenderingObserverList {
1.275 +public:
1.276 + nsSVGRenderingObserverList()
1.277 + : mObservers(5)
1.278 + {
1.279 + MOZ_COUNT_CTOR(nsSVGRenderingObserverList);
1.280 + }
1.281 +
1.282 + ~nsSVGRenderingObserverList() {
1.283 + InvalidateAll();
1.284 + MOZ_COUNT_DTOR(nsSVGRenderingObserverList);
1.285 + }
1.286 +
1.287 + void Add(nsSVGRenderingObserver* aObserver)
1.288 + { mObservers.PutEntry(aObserver); }
1.289 + void Remove(nsSVGRenderingObserver* aObserver)
1.290 + { mObservers.RemoveEntry(aObserver); }
1.291 +#ifdef DEBUG
1.292 + bool Contains(nsSVGRenderingObserver* aObserver)
1.293 + { return (mObservers.GetEntry(aObserver) != nullptr); }
1.294 +#endif
1.295 + bool IsEmpty()
1.296 + { return mObservers.Count() == 0; }
1.297 +
1.298 + /**
1.299 + * Drop all our observers, and notify them that we have changed and dropped
1.300 + * our reference to them.
1.301 + */
1.302 + void InvalidateAll();
1.303 +
1.304 + /**
1.305 + * Drop all observers that observe reflow, and notify them that we have changed and dropped
1.306 + * our reference to them.
1.307 + */
1.308 + void InvalidateAllForReflow();
1.309 +
1.310 + /**
1.311 + * Drop all our observers, and notify them that we have dropped our reference
1.312 + * to them.
1.313 + */
1.314 + void RemoveAll();
1.315 +
1.316 +private:
1.317 + nsTHashtable<nsPtrHashKey<nsSVGRenderingObserver> > mObservers;
1.318 +};
1.319 +
1.320 +class nsSVGEffects {
1.321 +public:
1.322 + typedef mozilla::dom::Element Element;
1.323 + typedef mozilla::FramePropertyDescriptor FramePropertyDescriptor;
1.324 + typedef nsInterfaceHashtable<nsURIHashKey, nsIMutationObserver>
1.325 + URIObserverHashtable;
1.326 +
1.327 + static void DestroySupports(void* aPropertyValue)
1.328 + {
1.329 + (static_cast<nsISupports*>(aPropertyValue))->Release();
1.330 + }
1.331 +
1.332 + static void DestroyHashtable(void* aPropertyValue)
1.333 + {
1.334 + delete static_cast<URIObserverHashtable*> (aPropertyValue);
1.335 + }
1.336 +
1.337 + NS_DECLARE_FRAME_PROPERTY(FilterProperty, DestroySupports)
1.338 + NS_DECLARE_FRAME_PROPERTY(MaskProperty, DestroySupports)
1.339 + NS_DECLARE_FRAME_PROPERTY(ClipPathProperty, DestroySupports)
1.340 + NS_DECLARE_FRAME_PROPERTY(MarkerBeginProperty, DestroySupports)
1.341 + NS_DECLARE_FRAME_PROPERTY(MarkerMiddleProperty, DestroySupports)
1.342 + NS_DECLARE_FRAME_PROPERTY(MarkerEndProperty, DestroySupports)
1.343 + NS_DECLARE_FRAME_PROPERTY(FillProperty, DestroySupports)
1.344 + NS_DECLARE_FRAME_PROPERTY(StrokeProperty, DestroySupports)
1.345 + NS_DECLARE_FRAME_PROPERTY(HrefProperty, DestroySupports)
1.346 + NS_DECLARE_FRAME_PROPERTY(BackgroundImageProperty, DestroyHashtable)
1.347 +
1.348 + /**
1.349 + * Get the paint server for a aTargetFrame.
1.350 + */
1.351 + static nsSVGPaintServerFrame *GetPaintServer(nsIFrame *aTargetFrame,
1.352 + const nsStyleSVGPaint *aPaint,
1.353 + const FramePropertyDescriptor *aProperty);
1.354 +
1.355 + struct EffectProperties {
1.356 + nsSVGFilterProperty* mFilter;
1.357 + nsSVGPaintingProperty* mMask;
1.358 + nsSVGPaintingProperty* mClipPath;
1.359 +
1.360 + /**
1.361 + * @return the clip-path frame, or null if there is no clip-path frame
1.362 + * @param aOK if a clip-path was specified and the designated element
1.363 + * exists but is an element of the wrong type, *aOK is set to false.
1.364 + * Otherwise *aOK is untouched.
1.365 + */
1.366 + nsSVGClipPathFrame *GetClipPathFrame(bool *aOK);
1.367 + /**
1.368 + * @return the mask frame, or null if there is no mask frame
1.369 + * @param aOK if a mask was specified and the designated element
1.370 + * exists but is an element of the wrong type, *aOK is set to false.
1.371 + * Otherwise *aOK is untouched.
1.372 + */
1.373 + nsSVGMaskFrame *GetMaskFrame(bool *aOK);
1.374 +
1.375 + bool HasValidFilter() {
1.376 + return mFilter && mFilter->ReferencesValidResources();
1.377 + }
1.378 +
1.379 + bool HasNoFilterOrHasValidFilter() {
1.380 + return !mFilter || mFilter->ReferencesValidResources();
1.381 + }
1.382 + };
1.383 +
1.384 + /**
1.385 + * @param aFrame should be the first continuation
1.386 + */
1.387 + static EffectProperties GetEffectProperties(nsIFrame *aFrame);
1.388 +
1.389 + /**
1.390 + * Called when changes to an element (e.g. CSS property changes) cause its
1.391 + * frame to start/stop referencing (or reference different) SVG resource
1.392 + * elements. (_Not_ called for changes to referenced resource elements.)
1.393 + *
1.394 + * This function handles such changes by discarding _all_ the frame's SVG
1.395 + * effects frame properties (causing those properties to stop watching their
1.396 + * target element). It also synchronously (re)creates the filter and marker
1.397 + * frame properties (XXX why not the other properties?), which makes it
1.398 + * useful for initializing those properties during first reflow.
1.399 + *
1.400 + * XXX rename to something more meaningful like RefreshResourceReferences?
1.401 + */
1.402 + static void UpdateEffects(nsIFrame *aFrame);
1.403 +
1.404 + /**
1.405 + * @param aFrame should be the first continuation
1.406 + */
1.407 + static nsSVGFilterProperty *GetFilterProperty(nsIFrame *aFrame);
1.408 +
1.409 + /**
1.410 + * @param aFrame must be a first-continuation.
1.411 + */
1.412 + static void AddRenderingObserver(Element *aElement, nsSVGRenderingObserver *aObserver);
1.413 + /**
1.414 + * @param aFrame must be a first-continuation.
1.415 + */
1.416 + static void RemoveRenderingObserver(Element *aElement, nsSVGRenderingObserver *aObserver);
1.417 +
1.418 + /**
1.419 + * Removes all rendering observers from aElement.
1.420 + */
1.421 + static void RemoveAllRenderingObservers(Element *aElement);
1.422 +
1.423 + /**
1.424 + * This can be called on any frame. We invalidate the observers of aFrame's
1.425 + * element, if any, or else walk up to the nearest observable SVG parent
1.426 + * frame with observers and invalidate them instead.
1.427 + *
1.428 + * Note that this method is very different to e.g.
1.429 + * nsNodeUtils::AttributeChanged which walks up the content node tree all the
1.430 + * way to the root node (not stopping if it encounters a non-container SVG
1.431 + * node) invalidating all mutation observers (not just
1.432 + * nsSVGRenderingObservers) on all nodes along the way (not just the first
1.433 + * node it finds with observers). In other words, by doing all the
1.434 + * things in parentheses in the preceding sentence, this method uses
1.435 + * knowledge about our implementation and what can be affected by SVG effects
1.436 + * to make invalidation relatively lightweight when an SVG effect changes.
1.437 + */
1.438 + static void InvalidateRenderingObservers(nsIFrame *aFrame);
1.439 +
1.440 + enum {
1.441 + INVALIDATE_REFLOW = 1
1.442 + };
1.443 +
1.444 + /**
1.445 + * This can be called on any element or frame. Only direct observers of this
1.446 + * (frame's) element, if any, are invalidated.
1.447 + */
1.448 + static void InvalidateDirectRenderingObservers(Element *aElement, uint32_t aFlags = 0);
1.449 + static void InvalidateDirectRenderingObservers(nsIFrame *aFrame, uint32_t aFlags = 0);
1.450 +
1.451 + /**
1.452 + * Get an nsSVGMarkerProperty for the frame, creating a fresh one if necessary
1.453 + */
1.454 + static nsSVGMarkerProperty *
1.455 + GetMarkerProperty(nsIURI *aURI, nsIFrame *aFrame,
1.456 + const FramePropertyDescriptor *aProperty);
1.457 + /**
1.458 + * Get an nsSVGTextPathProperty for the frame, creating a fresh one if necessary
1.459 + */
1.460 + static nsSVGTextPathProperty *
1.461 + GetTextPathProperty(nsIURI *aURI, nsIFrame *aFrame,
1.462 + const FramePropertyDescriptor *aProperty);
1.463 + /**
1.464 + * Get an nsSVGPaintingProperty for the frame, creating a fresh one if necessary
1.465 + */
1.466 + static nsSVGPaintingProperty *
1.467 + GetPaintingProperty(nsIURI *aURI, nsIFrame *aFrame,
1.468 + const FramePropertyDescriptor *aProperty);
1.469 + /**
1.470 + * Get an nsSVGPaintingProperty for the frame for that URI, creating a fresh
1.471 + * one if necessary
1.472 + */
1.473 + static nsSVGPaintingProperty *
1.474 + GetPaintingPropertyForURI(nsIURI *aURI, nsIFrame *aFrame,
1.475 + const FramePropertyDescriptor *aProp);
1.476 +};
1.477 +
1.478 +#endif /*NSSVGEFFECTS_H_*/
