dom/smil/nsSMILRepeatCount.h

   1 /* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
   2 /* This Source Code Form is subject to the terms of the Mozilla Public
   3  * License, v. 2.0. If a copy of the MPL was not distributed with this
   4  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
   5
   6 #ifndef nsSMILRepeatCount_h
   7 #define nsSMILRepeatCount_h
   8
   9 #include "nsDebug.h"
  10 #include <math.h>
  11
  12 //----------------------------------------------------------------------
  13 // nsSMILRepeatCount
  14 //
  15 // A tri-state non-negative floating point number for representing the number of
  16 // times an animation repeat, i.e. the SMIL repeatCount attribute.
  17 //
  18 // The three states are:
  19 //  1. not-set
  20 //  2. set (with non-negative, non-zero count value)
  21 //  3. indefinite
  22 //
  23 class nsSMILRepeatCount
  24 {
  25 public:
  26   nsSMILRepeatCount() : mCount(kNotSet) {}
  27   explicit nsSMILRepeatCount(double aCount)
  28     : mCount(kNotSet) { SetCount(aCount); }
  29
  30   operator double() const {
  31     MOZ_ASSERT(IsDefinite(),
  32       "Converting indefinite or unset repeat count to double");
  33     return mCount;
  34   }
  35   bool IsDefinite() const {
  36     return mCount != kNotSet && mCount != kIndefinite;
  37   }
  38   bool IsIndefinite() const { return mCount == kIndefinite; }
  39   bool IsSet() const { return mCount != kNotSet; }
  40
  41   nsSMILRepeatCount& operator=(double aCount)
  42   {
  43     SetCount(aCount);
  44     return *this;
  45   }
  46   void SetCount(double aCount)
  47   {
  48     NS_ASSERTION(aCount > 0.0, "Negative or zero repeat count");
  49     mCount = aCount > 0.0 ? aCount : kNotSet;
  50   }
  51   void SetIndefinite() { mCount = kIndefinite; }
  52   void Unset() { mCount = kNotSet; }
  53
  54 private:
  55   static const double kNotSet;
  56   static const double kIndefinite;
  57
  58   double  mCount;
  59 };
  60
  61 #endif