tor-browser

DOMSVGTransform.h (5975B)

---

/* -*- 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
* file, You can obtain one at http://mozilla.org/MPL/2.0/. */

#ifndef DOM_SVG_DOMSVGTRANSFORM_H_
#define DOM_SVG_DOMSVGTRANSFORM_H_

#include "DOMSVGTransformList.h"
#include "SVGTransform.h"
#include "gfxMatrix.h"
#include "mozilla/UniquePtr.h"
#include "nsCycleCollectionParticipant.h"
#include "nsDebug.h"
#include "nsID.h"
#include "nsWrapperCache.h"

#define MOZ_SVG_LIST_INDEX_BIT_COUNT 31  // supports > 2 billion list items

namespace mozilla::dom {

struct DOMMatrix2DInit;
class SVGElement;
class SVGMatrix;

/**
* DOM wrapper for an SVG transform. See DOMSVGLength.h.
*/
class DOMSVGTransform final : public nsWrapperCache {
 template <class T>
 friend class AutoChangeTransformListNotifier;

public:
 NS_INLINE_DECL_CYCLE_COLLECTING_NATIVE_REFCOUNTING(DOMSVGTransform)
 NS_DECL_CYCLE_COLLECTION_SCRIPT_HOLDER_NATIVE_CLASS(DOMSVGTransform)

 /**
  * Generic ctor for DOMSVGTransform objects that are created for an attribute.
  */
 DOMSVGTransform(DOMSVGTransformList* aList, uint32_t aListIndex,
                 bool aIsAnimValItem);

 /**
  * Ctors for creating the objects returned by:
  *   SVGSVGElement.createSVGTransform(),
  *   SVGSVGElement.createSVGTransformFromMatrix(in DOMMatrix2DInit  matrix),
  *   SVGTransformList.createSVGTransformFromMatrix(in DOMMatrix2DInit  matrix)
  * which do not initially belong to an attribute.
  */
 DOMSVGTransform();
 explicit DOMSVGTransform(const gfxMatrix& aMatrix);
 DOMSVGTransform(const DOMMatrix2DInit& aMatrix, ErrorResult& aRv);

 /**
  * Ctor for creating an unowned copy. Used with Clone().
  */
 explicit DOMSVGTransform(const SVGTransform& aTransform);

 /**
  * Create an unowned copy of an owned transform. The caller is responsible for
  * the first AddRef().
  */
 DOMSVGTransform* Clone() {
   NS_ASSERTION(mList, "unexpected caller");
   return new DOMSVGTransform(InternalItem());
 }

 bool IsInList() const { return !!mList; }

 /**
  * Returns true if our attribute is animating (in which case our animVal is
  * not simply a mirror of our baseVal).
  */
 bool IsAnimating() const { return mList && mList->IsAnimating(); }

 /**
  * In future, if this class is used for non-list transforms, this will be
  * different to IsInList().
  */
 bool HasOwner() const { return !!mList; }

 /**
  * 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
  * DOMSVGTransformList).)
  */
 void InsertingIntoList(DOMSVGTransformList* 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();

 SVGTransform ToSVGTransform() const { return Transform(); }

 // WebIDL
 DOMSVGTransformList* GetParentObject() const { return mList; }
 JSObject* WrapObject(JSContext* aCx,
                      JS::Handle<JSObject*> aGivenProto) override;
 uint16_t Type() const;
 dom::SVGMatrix* GetMatrix();
 float Angle() const;
 void SetMatrix(const DOMMatrix2DInit& matrix, ErrorResult& aRv);
 void SetTranslate(float tx, float ty, ErrorResult& aRv);
 void SetScale(float sx, float sy, ErrorResult& aRv);
 void SetRotate(float angle, float cx, float cy, ErrorResult& aRv);
 void SetSkewX(float angle, ErrorResult& aRv);
 void SetSkewY(float angle, ErrorResult& aRv);

protected:
 ~DOMSVGTransform();

 // Interface for SVGMatrix's use
 friend class dom::SVGMatrix;
 bool IsAnimVal() const { return mIsAnimValItem; }
 const gfxMatrix& Matrixgfx() const { return Transform().GetMatrix(); }
 void SetMatrix(const gfxMatrix& aMatrix);

private:
 SVGElement* Element() { return mList->Element(); }

 /**
  * Get a reference to the internal SVGTransform list item that this DOM
  * wrapper object currently wraps.
  */
 SVGTransform& InternalItem();
 const SVGTransform& InternalItem() const;

#ifdef DEBUG
 bool IndexIsValid();
#endif

 const SVGTransform& Transform() const {
   return HasOwner() ? InternalItem() : *mTransform;
 }
 SVGTransform& Transform() {
   return HasOwner() ? InternalItem() : *mTransform;
 }

 RefPtr<DOMSVGTransformList> mList;

 // 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;

 // Usually this class acts as a wrapper for an SVGTransform object which is
 // part of a list and is accessed by going via the owning Element.
 //
 // However, in some circumstances, objects of this class may not be associated
 // with any particular list and thus, no internal SVGTransform object. In
 // that case we allocate an SVGTransform object on the heap to store the
 // data.
 UniquePtr<SVGTransform> mTransform;
};

}  // namespace mozilla::dom

#undef MOZ_SVG_LIST_INDEX_BIT_COUNT

#endif  // DOM_SVG_DOMSVGTRANSFORM_H_