dom/svg/SVGAnimatedLengthList.h

   1 /* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
   2 /* vim: set ts=8 sts=2 et sw=2 tw=80: */
   3 /* This Source Code Form is subject to the terms of the Mozilla Public
   4  * License, v. 2.0. If a copy of the MPL was not distributed with this
   5  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
   6
   7 #ifndef DOM_SVG_SVGANIMATEDLENGTHLIST_H_
   8 #define DOM_SVG_SVGANIMATEDLENGTHLIST_H_
   9
  10 #include "mozilla/Attributes.h"
  11 #include "mozilla/SMILAttr.h"
  12 #include "mozilla/UniquePtr.h"
  13 #include "SVGLengthList.h"
  14
  15 namespace mozilla {
  16
  17 class SMILValue;
  18
  19 namespace dom {
  20 class SVGAnimationElement;
  21 class SVGElement;
  22 }  // namespace dom
  23
  24 /**
  25  * Class SVGAnimatedLengthList
  26  *
  27  * This class is very different to the SVG DOM interface of the same name found
  28  * in the SVG specification. This is a lightweight internal class - see
  29  * DOMSVGAnimatedLengthList for the heavier DOM class that wraps instances of
  30  * this class and implements the SVG specification's SVGAnimatedLengthList DOM
  31  * interface.
  32  *
  33  * Except where noted otherwise, this class' methods take care of keeping the
  34  * appropriate DOM wrappers in sync (see the comment in
  35  * DOMSVGAnimatedLengthList::InternalBaseValListWillChangeTo) so that their
  36  * consumers don't need to concern themselves with that.
  37  */
  38 class SVGAnimatedLengthList {
  39   // friends so that they can get write access to mBaseVal
  40   friend class dom::DOMSVGLength;
  41   friend class dom::DOMSVGLengthList;
  42
  43  public:
  44   SVGAnimatedLengthList() = default;
  45
  46   SVGAnimatedLengthList& operator=(const SVGAnimatedLengthList& aOther) {
  47     mBaseVal = aOther.mBaseVal;
  48     if (aOther.mAnimVal) {
  49       mAnimVal = MakeUnique<SVGLengthList>(*aOther.mAnimVal);
  50     }
  51     return *this;
  52   }
  53
  54   /**
  55    * Because it's so important that mBaseVal and its DOMSVGLengthList wrapper
  56    * (if any) be kept in sync (see the comment in
  57    * DOMSVGAnimatedLengthList::InternalBaseValListWillChangeTo), this method
  58    * returns a const reference. Only our friend classes may get mutable
  59    * references to mBaseVal.
  60    */
  61   const SVGLengthList& GetBaseValue() const { return mBaseVal; }
  62
  63   nsresult SetBaseValueString(const nsAString& aValue);
  64
  65   void ClearBaseValue(uint32_t aAttrEnum);
  66
  67   const SVGLengthList& GetAnimValue() const {
  68     return mAnimVal ? *mAnimVal : mBaseVal;
  69   }
  70
  71   nsresult SetAnimValue(const SVGLengthList& aNewAnimValue,
  72                         dom::SVGElement* aElement, uint32_t aAttrEnum);
  73
  74   void ClearAnimValue(dom::SVGElement* aElement, uint32_t aAttrEnum);
  75
  76   bool IsAnimating() const { return !!mAnimVal; }
  77
  78   UniquePtr<SMILAttr> ToSMILAttr(dom::SVGElement* aSVGElement,
  79                                  uint8_t aAttrEnum, uint8_t aAxis,
  80                                  bool aCanZeroPadList);
  81
  82  private:
  83   // mAnimVal is a pointer to allow us to determine if we're being animated or
  84   // not. Making it a non-pointer member and using mAnimVal.IsEmpty() to check
  85   // if we're animating is not an option, since that would break animation *to*
  86   // the empty string (<set to="">).
  87
  88   SVGLengthList mBaseVal;
  89   UniquePtr<SVGLengthList> mAnimVal;
  90
  91   struct SMILAnimatedLengthList : public SMILAttr {
  92    public:
  93     SMILAnimatedLengthList(SVGAnimatedLengthList* aVal,
  94                            dom::SVGElement* aSVGElement, uint8_t aAttrEnum,
  95                            uint8_t aAxis, bool aCanZeroPadList)
  96         : mVal(aVal),
  97           mElement(aSVGElement),
  98           mAttrEnum(aAttrEnum),
  99           mAxis(aAxis),
 100           mCanZeroPadList(aCanZeroPadList) {}
 101
 102     // These will stay alive because a SMILAttr only lives as long
 103     // as the Compositing step, and DOM elements don't get a chance to
 104     // die during that.
 105     SVGAnimatedLengthList* mVal;
 106     dom::SVGElement* mElement;
 107     uint8_t mAttrEnum;
 108     uint8_t mAxis;
 109     bool mCanZeroPadList;  // See SVGLengthListAndInfo::CanZeroPadList
 110
 111     // SMILAttr methods
 112     nsresult ValueFromString(const nsAString& aStr,
 113                              const dom::SVGAnimationElement* aSrcElement,
 114                              SMILValue& aValue,
 115                              bool& aPreventCachingOfSandwich) const override;
 116     SMILValue GetBaseValue() const override;
 117     void ClearAnimValue() override;
 118     nsresult SetAnimValue(const SMILValue& aValue) override;
 119   };
 120 };
 121
 122 }  // namespace mozilla
 123
 124 #endif  // DOM_SVG_SVGANIMATEDLENGTHLIST_H_