dom/smil/nsSMILFloatType.cpp

   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 #include "nsSMILFloatType.h"
   7 #include "nsSMILValue.h"
   8 #include "nsDebug.h"
   9 #include <math.h>
  10
  11 void
  12 nsSMILFloatType::Init(nsSMILValue& aValue) const
  13 {
  14   NS_PRECONDITION(aValue.IsNull(), "Unexpected value type");
  15   aValue.mU.mDouble = 0.0;
  16   aValue.mType = this;
  17 }
  18
  19 void
  20 nsSMILFloatType::Destroy(nsSMILValue& aValue) const
  21 {
  22   NS_PRECONDITION(aValue.mType == this, "Unexpected SMIL value");
  23   aValue.mU.mDouble = 0.0;
  24   aValue.mType      = nsSMILNullType::Singleton();
  25 }
  26
  27 nsresult
  28 nsSMILFloatType::Assign(nsSMILValue& aDest, const nsSMILValue& aSrc) const
  29 {
  30   NS_PRECONDITION(aDest.mType == aSrc.mType, "Incompatible SMIL types");
  31   NS_PRECONDITION(aDest.mType == this, "Unexpected SMIL value");
  32   aDest.mU.mDouble = aSrc.mU.mDouble;
  33   return NS_OK;
  34 }
  35
  36 bool
  37 nsSMILFloatType::IsEqual(const nsSMILValue& aLeft,
  38                          const nsSMILValue& aRight) const
  39 {
  40   NS_PRECONDITION(aLeft.mType == aRight.mType, "Incompatible SMIL types");
  41   NS_PRECONDITION(aLeft.mType == this, "Unexpected type for SMIL value");
  42
  43   return aLeft.mU.mDouble == aRight.mU.mDouble;
  44 }
  45
  46 nsresult
  47 nsSMILFloatType::Add(nsSMILValue& aDest, const nsSMILValue& aValueToAdd,
  48                      uint32_t aCount) const
  49 {
  50   NS_PRECONDITION(aValueToAdd.mType == aDest.mType,
  51                   "Trying to add invalid types");
  52   NS_PRECONDITION(aValueToAdd.mType == this, "Unexpected source type");
  53   aDest.mU.mDouble += aValueToAdd.mU.mDouble * aCount;
  54   return NS_OK;
  55 }
  56
  57 nsresult
  58 nsSMILFloatType::ComputeDistance(const nsSMILValue& aFrom,
  59                                  const nsSMILValue& aTo,
  60                                  double& aDistance) const
  61 {
  62   NS_PRECONDITION(aFrom.mType == aTo.mType,"Trying to compare different types");
  63   NS_PRECONDITION(aFrom.mType == this, "Unexpected source type");
  64
  65   const double &from = aFrom.mU.mDouble;
  66   const double &to   = aTo.mU.mDouble;
  67
  68   aDistance = fabs(to - from);
  69
  70   return NS_OK;
  71 }
  72
  73 nsresult
  74 nsSMILFloatType::Interpolate(const nsSMILValue& aStartVal,
  75                              const nsSMILValue& aEndVal,
  76                              double aUnitDistance,
  77                              nsSMILValue& aResult) const
  78 {
  79   NS_PRECONDITION(aStartVal.mType == aEndVal.mType,
  80       "Trying to interpolate different types");
  81   NS_PRECONDITION(aStartVal.mType == this,
  82       "Unexpected types for interpolation");
  83   NS_PRECONDITION(aResult.mType   == this, "Unexpected result type");
  84
  85   const double &startVal = aStartVal.mU.mDouble;
  86   const double &endVal   = aEndVal.mU.mDouble;
  87
  88   aResult.mU.mDouble = (startVal + (endVal - startVal) * aUnitDistance);
  89
  90   return NS_OK;
  91 }