gecko-dev/dom/svg/SVGAnimatedTransformList.h

155 строки
5.4 KiB
C++

/* -*- 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_SVGANIMATEDTRANSFORMLIST_H_
#define DOM_SVG_SVGANIMATEDTRANSFORMLIST_H_
#include "mozilla/Attributes.h"
#include "mozilla/SMILAttr.h"
#include "mozilla/UniquePtr.h"
#include "SVGTransformList.h"
class nsAtom;
namespace mozilla {
class SMILValue;
namespace dom {
class SVGAnimationElement;
class SVGElement;
class DOMSVGTransform;
} // namespace dom
/**
* Class SVGAnimatedTransformList
*
* This class is very different to the SVG DOM interface of the same name found
* in the SVG specification. This is a lightweight internal class - see
* DOMSVGAnimatedTransformList for the heavier DOM class that wraps instances of
* this class and implements the SVG specification's SVGAnimatedTransformList
* DOM interface.
*
* Except where noted otherwise, this class' methods take care of keeping the
* appropriate DOM wrappers in sync (see the comment in
* DOMSVGAnimatedTransformList::InternalBaseValListWillChangeTo) so that their
* consumers don't need to concern themselves with that.
*/
class SVGAnimatedTransformList {
// friends so that they can get write access to mBaseVal
friend class dom::DOMSVGTransform;
friend class dom::DOMSVGTransformList;
public:
SVGAnimatedTransformList()
: mIsAttrSet(false), mCreatedOrRemovedOnLastChange(true) {}
/**
* Because it's so important that mBaseVal and its DOMSVGTransformList wrapper
* (if any) be kept in sync (see the comment in
* DOMSVGAnimatedTransformList::InternalBaseValListWillChangeTo), this method
* returns a const reference. Only our friend classes may get mutable
* references to mBaseVal.
*/
const SVGTransformList& GetBaseValue() const { return mBaseVal; }
nsresult SetBaseValue(const SVGTransformList& aValue,
dom::SVGElement* aSVGElement);
nsresult SetBaseValueString(const nsAString& aValue,
dom::SVGElement* aSVGElement);
void ClearBaseValue();
const SVGTransformList& GetAnimValue() const {
return mAnimVal ? *mAnimVal : mBaseVal;
}
nsresult SetAnimValue(const SVGTransformList& aValue,
dom::SVGElement* aElement);
void ClearAnimValue(dom::SVGElement* aElement);
/**
* Returns true if the corresponding transform attribute is set (or animated)
* to a valid value. Unlike HasTransform it will return true for an empty
* transform.
*/
bool IsExplicitlySet() const;
/**
* Returns true if the corresponding transform attribute is set (or animated)
* to a valid value, such that we have at least one transform in our list.
* Returns false otherwise (e.g. if the transform attribute is missing or
* empty or invalid).
*/
bool HasTransform() const {
return (mAnimVal && !mAnimVal->IsEmpty()) || !mBaseVal.IsEmpty();
}
bool IsAnimating() const { return !!mAnimVal; }
/**
* Returns true if the last change of this transform went from having to not
* having a transform or vice versa.
*
* (This is used as part of an optimization in
* SVGTransformableElement::GetAttributeChangeHint. That function reports an
* inexpensive nsChangeHint when a transform has just modified -- but this
* accessor lets it detect cases where the "modification" is actually creating
* a transform where we previously had none. These cases require a more
* thorough nsChangeHint.)
*/
bool CreatedOrRemovedOnLastChange() const {
return mCreatedOrRemovedOnLastChange;
}
UniquePtr<SMILAttr> ToSMILAttr(dom::SVGElement* aSVGElement);
private:
// mAnimVal is a pointer to allow us to determine if we're being animated or
// not. Making it a non-pointer member and using mAnimVal.IsEmpty() to check
// if we're animating is not an option, since that would break animation *to*
// the empty string (<set to="">).
SVGTransformList mBaseVal;
UniquePtr<SVGTransformList> mAnimVal;
bool mIsAttrSet;
// See documentation for accessor.
bool mCreatedOrRemovedOnLastChange;
struct SMILAnimatedTransformList : public SMILAttr {
public:
SMILAnimatedTransformList(SVGAnimatedTransformList* aVal,
dom::SVGElement* aSVGElement)
: mVal(aVal), mElement(aSVGElement) {}
// SMILAttr methods
virtual nsresult ValueFromString(
const nsAString& aStr, const dom::SVGAnimationElement* aSrcElement,
SMILValue& aValue, bool& aPreventCachingOfSandwich) const override;
virtual SMILValue GetBaseValue() const override;
virtual void ClearAnimValue() override;
virtual nsresult SetAnimValue(const SMILValue& aNewAnimValue) override;
protected:
static void ParseValue(const nsAString& aSpec, const nsAtom* aTransformType,
SMILValue& aResult);
static int32_t ParseParameterList(const nsAString& aSpec, float* aVars,
int32_t aNVars);
// These will stay alive because a SMILAttr only lives as long
// as the Compositing step, and DOM elements don't get a chance to
// die during that.
SVGAnimatedTransformList* mVal;
dom::SVGElement* mElement;
};
};
} // namespace mozilla
#endif // DOM_SVG_SVGANIMATEDTRANSFORMLIST_H_