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/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* vim: set ts=8 sts=2 et sw=2 tw=80: */
/* 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
#ifndef DOM_SVG_DOMSVGPOINT_H_
#define DOM_SVG_DOMSVGPOINT_H_
#include "DOMSVGPointList.h"
#include "nsCycleCollectionParticipant.h"
#include "nsDebug.h"
#include "SVGPoint.h"
#include "nsWrapperCache.h"
#include "mozilla/Attributes.h"
#include "mozilla/FloatingPoint.h"
#include "mozilla/dom/SVGSVGElement.h"
#include "mozilla/gfx/2D.h"
#define MOZ_SVG_LIST_INDEX_BIT_COUNT 30
namespace mozilla::dom {
struct DOMMatrix2DInit;
/**
* Class DOMSVGPoint
*
* This class creates the DOM objects that wrap internal SVGPoint objects that
* are in an SVGPointList. It is also used to create the objects returned by
* SVGSVGElement.createSVGPoint() and other functions that return DOM SVGPoint
* objects.
*
* See the architecture comment in DOMSVGPointList.h for an overview of the
* important points regarding these DOM wrapper structures.
*
* See the architecture comment in DOMSVGLength.h (yes, LENGTH) for an overview
* of the important points regarding how this specific class works.
*/
class DOMSVGPoint final : public nsWrapperCache {
template <class T>
friend class AutoChangePointListNotifier;
using Point = gfx::Point;
public:
/**
* Generic ctor for DOMSVGPoint objects that are created for an attribute.
*/
DOMSVGPoint(DOMSVGPointList* aList, uint32_t aListIndex, bool aIsAnimValItem)
: mVal(nullptr),
mOwner(aList),
mListIndex(aListIndex),
mIsAnimValItem(aIsAnimValItem),
mIsTranslatePoint(false) {
// These shifts are in sync with the members.
MOZ_ASSERT(aList && aListIndex <= MaxListIndex(), "bad arg");
MOZ_ASSERT(IndexIsValid(), "Bad index for DOMSVGPoint!");
}
// Constructor for unowned points and SVGSVGElement.createSVGPoint
explicit DOMSVGPoint(const Point& aPt)
: mListIndex(0), mIsAnimValItem(false), mIsTranslatePoint(false) {
// In this case we own mVal
mVal = new SVGPoint(aPt.x, aPt.y);
}
private:
// The translate of an SVGSVGElement
DOMSVGPoint(SVGPoint* aPt, SVGSVGElement* aSVGSVGElement)
: mVal(aPt),
mOwner(ToSupports(aSVGSVGElement)),
mListIndex(0),
mIsAnimValItem(false),
mIsTranslatePoint(true) {}
virtual ~DOMSVGPoint() { CleanupWeakRefs(); }
public:
NS_INLINE_DECL_CYCLE_COLLECTING_NATIVE_REFCOUNTING(DOMSVGPoint)
NS_DECL_CYCLE_COLLECTION_SCRIPT_HOLDER_NATIVE_CLASS(DOMSVGPoint)
static already_AddRefed<DOMSVGPoint> GetTranslateTearOff(
SVGPoint* aVal, SVGSVGElement* aSVGSVGElement);
bool IsInList() const { return HasOwner() && !IsTranslatePoint(); }
/**
* "Owner" here means that the instance has an
* internal counterpart from which it gets its values. (A better name may
* be HasWrappee().)
*/
bool HasOwner() const { return !!mOwner; }
bool IsTranslatePoint() const { return mIsTranslatePoint; }
void DidChangeTranslate();
/**
* This method is called to notify this DOM object that it is being inserted
* into a list, and give it the information it needs as a result.
*
* This object MUST NOT already belong to a list when this method is called.
* That's not to say that script can't move these DOM objects between
* lists - it can - it's just that the logic to handle that (and send out
* the necessary notifications) is located elsewhere (in DOMSVGPointList).)
*/
void InsertingIntoList(DOMSVGPointList* aList, uint32_t aListIndex,
bool aIsAnimValItem);
static uint32_t MaxListIndex() {
return (1U << MOZ_SVG_LIST_INDEX_BIT_COUNT) - 1;
}
/// This method is called to notify this object that its list index changed.
void UpdateListIndex(uint32_t aListIndex) { mListIndex = aListIndex; }
/**
* This method is called to notify this DOM object that it is about to be
* removed from its current DOM list so that it can first make a copy of its
* internal counterpart's values. (If it didn't do this, then it would
* "lose" its value on being removed.)
*/
void RemovingFromList();
SVGPoint ToSVGPoint() { return InternalItem(); }
// WebIDL
float X();
void SetX(float aX, ErrorResult& rv);
float Y();
void SetY(float aY, ErrorResult& rv);
already_AddRefed<DOMSVGPoint> MatrixTransform(const DOMMatrix2DInit& aMatrix,
ErrorResult& aRv);
nsISupports* GetParentObject() { return Element(); }
/**
* Returns true if our attribute is animating (in which case our animVal is
* not simply a mirror of our baseVal).
*/
bool AttrIsAnimating() const;
JSObject* WrapObject(JSContext* cx,
JS::Handle<JSObject*> aGivenProto) override;
DOMSVGPoint* Copy() { return new DOMSVGPoint(InternalItem()); }
private:
#ifdef DEBUG
bool IndexIsValid();
#endif
SVGElement* Element();
/**
* Clears soon-to-be-invalid weak references in external objects that were
* set up during the creation of this object. This should be called during
* destruction and during cycle collection.
*/
void CleanupWeakRefs();
/**
* Get a reference to the internal SVGPoint list item that this DOM wrapper
* object currently wraps.
*/
SVGPoint& InternalItem();
SVGPoint* mVal; // If mIsTranslatePoint is true, the element owns
// the value. Otherwise we do.
RefPtr<nsISupports> mOwner; // If mIsTranslatePoint is true, this is an
// SVGSVGElement, if we're unowned it's null, or
// we're in a list and it's a DOMSVGPointList
// Bounds for the following are checked in the ctor, so be sure to update
// that if you change the capacity of any of the following.
uint32_t mListIndex : MOZ_SVG_LIST_INDEX_BIT_COUNT;
uint32_t mIsAnimValItem : 1; // True if We're the animated value of a list
uint32_t mIsTranslatePoint : 1; // true iff our owner is a SVGSVGElement
};
} // namespace mozilla::dom
#undef MOZ_SVG_LIST_INDEX_BIT_COUNT
#endif // DOM_SVG_DOMSVGPOINT_H_