gecko-dev/dom/smil/SMILCSSValueType.h

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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
* file, You can obtain one at http://mozilla.org/MPL/2.0/. */
/* representation of a value for a SMIL-animated CSS property */
#ifndef mozilla_SMILCSSValueType_h
#define mozilla_SMILCSSValueType_h
#include "mozilla/Attributes.h"
#include "mozilla/SMILType.h"
#include "nsCSSPropertyID.h"
#include "nsStringFwd.h"
namespace mozilla {
struct AnimationValue;
class DeclarationBlock;
namespace dom {
class Element;
} // namespace dom
/*
* SMILCSSValueType: Represents a SMIL-animated CSS value.
*/
class SMILCSSValueType : public SMILType {
public:
// Singleton for SMILValue objects to hold onto.
static SMILCSSValueType sSingleton;
protected:
// SMILType Methods
// -------------------
void Init(SMILValue& aValue) const override;
void Destroy(SMILValue&) const override;
nsresult Assign(SMILValue& aDest, const SMILValue& aSrc) const override;
bool IsEqual(const SMILValue& aLeft, const SMILValue& aRight) const override;
nsresult Add(SMILValue& aDest, const SMILValue& aValueToAdd,
uint32_t aCount) const override;
nsresult SandwichAdd(SMILValue& aDest,
const SMILValue& aValueToAdd) const override;
nsresult ComputeDistance(const SMILValue& aFrom, const SMILValue& aTo,
double& aDistance) const override;
nsresult Interpolate(const SMILValue& aStartVal, const SMILValue& aEndVal,
double aUnitDistance, SMILValue& aResult) const override;
public:
// Helper Methods
// --------------
/**
* Sets up the given SMILValue to represent the given string value. The
* string is interpreted as a value for the given property on the given
* element.
*
* On failure, this method leaves aValue.mType == SMILNullType::sSingleton.
* Otherwise, this method leaves aValue.mType == this class's singleton.
*
* @param aPropID The property for which we're parsing a value.
* @param aTargetElement The target element to whom the property/value
* setting applies.
* @param aString The string to be parsed as a CSS value.
* @param [out] aValue The SMILValue to be populated. Should
* initially be null-typed.
* @param [out] aIsContextSensitive Set to true if |aString| may produce
* a different |aValue| depending on other
* CSS properties on |aTargetElement|
* or its ancestors (e.g. 'inherit).
* false otherwise. May be nullptr.
* Not set if the method fails.
* @pre aValue.IsNull()
* @post aValue.IsNull() || aValue.mType == SMILCSSValueType::sSingleton
*/
static void ValueFromString(nsCSSPropertyID aPropID,
dom::Element* aTargetElement,
const nsAString& aString, SMILValue& aValue,
bool* aIsContextSensitive);
/**
* Creates a SMILValue to wrap the given animation value.
*
* @param aPropID The property that |aValue| corresponds to.
* @param aTargetElement The target element to which the animation value
* applies.
* @param aValue The animation value to use.
* @return A new SMILValue. On failure, returns a
* SMILValue with the null type (i.e. rv.IsNull()
* returns true).
*/
static SMILValue ValueFromAnimationValue(nsCSSPropertyID aPropID,
dom::Element* aTargetElement,
const AnimationValue& aValue);
/**
* Sets the relevant property values in the declaration block.
*
* Returns whether the declaration changed.
*/
static bool SetPropertyValues(const SMILValue&, mozilla::DeclarationBlock&);
/**
* Return the CSS property animated by the specified value.
*
* @param aValue The SMILValue to examine.
* @return The nsCSSPropertyID enum value of the property animated
* by |aValue|, or eCSSProperty_UNKNOWN if the type of
* |aValue| is not SMILCSSValueType.
*/
static nsCSSPropertyID PropertyFromValue(const SMILValue& aValue);
/**
* If |aValue| is an empty value, converts it to a suitable zero value by
* matching the type of value stored in |aValueToMatch|.
*
* There is no indication if this method fails. If a suitable zero value could
* not be created, |aValue| is simply unmodified.
*
* @param aValue The SMILValue (of type SMILCSSValueType) to
* possibly update.
* @param aValueToMatch A SMILValue (of type SMILCSSValueType) for which
* a corresponding zero value will be created if |aValue|
* is empty.
*/
static void FinalizeValue(SMILValue& aValue, const SMILValue& aValueToMatch);
private:
// Private constructor: prevent instances beyond my singleton.
constexpr SMILCSSValueType() = default;
};
} // namespace mozilla
#endif // mozilla_SMILCSSValueType_h