dom/svg/SVGAnimatedNumberList.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_SVGANIMATEDNUMBERLIST_H_
   8 #define DOM_SVG_SVGANIMATEDNUMBERLIST_H_
   9
  10 #include "mozilla/Attributes.h"
  11 #include "mozilla/SMILAttr.h"
  12 #include "mozilla/UniquePtr.h"
  13 #include "SVGNumberList.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 SVGAnimatedNumberList
  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  * DOMSVGAnimatedNumberList for the heavier DOM class that wraps instances of
  30  * this class and implements the SVG specification's SVGAnimatedNumberList 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  * DOMSVGAnimatedNumberList::InternalBaseValListWillChangeTo) so that their
  36  * consumers don't need to concern themselves with that.
  37  */
  38 class SVGAnimatedNumberList {
  39   // friends so that they can get write access to mBaseVal
  40   friend class dom::DOMSVGNumber;
  41   friend class dom::DOMSVGNumberList;
  42
  43  public:
  44   SVGAnimatedNumberList() = default;
  45
  46   SVGAnimatedNumberList& operator=(const SVGAnimatedNumberList& aOther) {
  47     mIsBaseSet = aOther.mIsBaseSet;
  48     mBaseVal = aOther.mBaseVal;
  49     if (aOther.mAnimVal) {
  50       mAnimVal = MakeUnique<SVGNumberList>(*aOther.mAnimVal);
  51     }
  52     return *this;
  53   }
  54
  55   /**
  56    * Because it's so important that mBaseVal and its DOMSVGNumberList wrapper
  57    * (if any) be kept in sync (see the comment in
  58    * DOMSVGAnimatedNumberList::InternalBaseValListWillChangeTo), this method
  59    * returns a const reference. Only our friend classes may get mutable
  60    * references to mBaseVal.
  61    */
  62   const SVGNumberList& GetBaseValue() const { return mBaseVal; }
  63
  64   nsresult SetBaseValueString(const nsAString& aValue);
  65
  66   void ClearBaseValue(uint32_t aAttrEnum);
  67
  68   const SVGNumberList& GetAnimValue() const {
  69     return mAnimVal ? *mAnimVal : mBaseVal;
  70   }
  71
  72   nsresult SetAnimValue(const SVGNumberList& aNewAnimValue,
  73                         dom::SVGElement* aElement, uint32_t aAttrEnum);
  74
  75   void ClearAnimValue(dom::SVGElement* aElement, uint32_t aAttrEnum);
  76
  77   // Returns true if the animated value of this list has been explicitly
  78   // set (either by animation, or by taking on the base value which has been
  79   // explicitly set by markup or a DOM call), false otherwise.
  80   // If this returns false, the animated value is still valid, that is,
  81   // usable, and represents the default base value of the attribute.
  82   bool IsExplicitlySet() const { return !!mAnimVal || mIsBaseSet; }
  83
  84   bool IsAnimating() const { return !!mAnimVal; }
  85
  86   UniquePtr<SMILAttr> ToSMILAttr(dom::SVGElement* aSVGElement,
  87                                  uint8_t aAttrEnum);
  88
  89  private:
  90   // mAnimVal is a pointer to allow us to determine if we're being animated or
  91   // not. Making it a non-pointer member and using mAnimVal.IsEmpty() to check
  92   // if we're animating is not an option, since that would break animation *to*
  93   // the empty string (<set to="">).
  94
  95   SVGNumberList mBaseVal;
  96   UniquePtr<SVGNumberList> mAnimVal;
  97   bool mIsBaseSet = false;
  98
  99   struct SMILAnimatedNumberList : public SMILAttr {
 100    public:
 101     SMILAnimatedNumberList(SVGAnimatedNumberList* aVal,
 102                            dom::SVGElement* aSVGElement, uint8_t aAttrEnum)
 103         : mVal(aVal), mElement(aSVGElement), mAttrEnum(aAttrEnum) {}
 104
 105     // These will stay alive because a SMILAttr only lives as long
 106     // as the Compositing step, and DOM elements don't get a chance to
 107     // die during that.
 108     SVGAnimatedNumberList* mVal;
 109     dom::SVGElement* mElement;
 110     uint8_t mAttrEnum;
 111
 112     // SMILAttr methods
 113     nsresult ValueFromString(const nsAString& aStr,
 114                              const dom::SVGAnimationElement* aSrcElement,
 115                              SMILValue& aValue,
 116                              bool& aPreventCachingOfSandwich) const override;
 117     SMILValue GetBaseValue() const override;
 118     void ClearAnimValue() override;
 119     nsresult SetAnimValue(const SMILValue& aValue) override;
 120   };
 121 };
 122
 123 }  // namespace mozilla
 124
 125 #endif  // DOM_SVG_SVGANIMATEDNUMBERLIST_H_