gecko-dev/layout/style/StyleAnimationValue.h

/* -*- 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/. */

/* Utilities for animation of computed style values */

#ifndef mozilla_StyleAnimationValue_h_
#define mozilla_StyleAnimationValue_h_

#include "mozilla/gfx/MatrixFwd.h"
#include "mozilla/gfx/Point.h"
#include "mozilla/ServoBindingTypes.h"
#include "mozilla/UniquePtr.h"
#include "nsStringFwd.h"
#include "nsStringBuffer.h"
#include "nsCoord.h"
#include "nsColor.h"
#include "nsCSSPropertyID.h"
#include "nsCSSValue.h"
#include "nsStyleCoord.h"
#include "nsStyleTransformMatrix.h"

class nsIFrame;
class gfx3DMatrix;

namespace mozilla {

class ComputedStyle;

namespace css {
class StyleRule;
} // namespace css

namespace dom {
class Element;
} // namespace dom

enum class CSSPseudoElementType : uint8_t;
struct PropertyStyleAnimationValuePair;


struct AnimationValue
{
  explicit AnimationValue(const RefPtr<RawServoAnimationValue>& aValue)
    : mServo(aValue) { }
  AnimationValue() = default;

  AnimationValue(const AnimationValue& aOther)
    : mServo(aOther.mServo) { }
  AnimationValue(AnimationValue&& aOther)
    : mServo(std::move(aOther.mServo)) { }

  AnimationValue& operator=(const AnimationValue& aOther)
  {
    if (this != &aOther) {
      mServo = aOther.mServo;
    }
    return *this;
  }
  AnimationValue& operator=(AnimationValue&& aOther)
  {
    MOZ_ASSERT(this != &aOther, "Do not move itself");
    if (this != &aOther) {
      mServo = std::move(aOther.mServo);
    }
    return *this;
  }

  bool operator==(const AnimationValue& aOther) const;
  bool operator!=(const AnimationValue& aOther) const;

  bool IsNull() const
  {
    return !mServo;
  }

  float GetOpacity() const;

  // Return the transform list as a RefPtr.
  already_AddRefed<const nsCSSValueSharedList> GetTransformList() const;

  // Return the scale for mServo, which is calculated with reference to aFrame.
  mozilla::gfx::Size GetScaleValue(const nsIFrame* aFrame) const;

  // Uncompute this AnimationValue and then serialize it.
  void SerializeSpecifiedValue(nsCSSPropertyID aProperty,
                               nsAString& aString) const;

  // Check if |*this| and |aToValue| can be interpolated.
  bool IsInterpolableWith(nsCSSPropertyID aProperty,
                          const AnimationValue& aToValue) const;

  // Compute the distance between *this and aOther.
  // If |aComputedStyle| is nullptr, we will return 0.0 if we have mismatched
  // transform lists.
  double ComputeDistance(nsCSSPropertyID aProperty,
                         const AnimationValue& aOther,
                         ComputedStyle* aComputedStyle) const;

  // Create an AnimaitonValue from a string. This method flushes style, so we
  // should use this carefully. Now, it is only used by
  // nsDOMWindowUtils::ComputeAnimationDistance.
  static AnimationValue FromString(nsCSSPropertyID aProperty,
                                   const nsAString& aValue,
                                   dom::Element* aElement);

  // Create an AnimationValue from an opacity value.
  static AnimationValue Opacity(float aOpacity);
  // Create an AnimationValue from a transform list.
  static AnimationValue Transform(nsCSSValueSharedList& aList);

  static already_AddRefed<nsCSSValue::Array>
  AppendTransformFunction(nsCSSKeyword aTransformFunction,
                          nsCSSValueList**& aListTail);

  RefPtr<RawServoAnimationValue> mServo;
};

struct PropertyStyleAnimationValuePair
{
  nsCSSPropertyID mProperty;
  AnimationValue mValue;
};
} // namespace mozilla

#endif