dali/internal/update/animation/scene-graph-constraint.h

   1 #ifndef __DALI_INTERNAL_SCENE_GRAPH_CONSTRAINT_H__
   2 #define __DALI_INTERNAL_SCENE_GRAPH_CONSTRAINT_H__
   3
   4 //
   5 // Copyright (c) 2014 Samsung Electronics Co., Ltd.
   6 //
   7 // Licensed under the Flora License, Version 1.0 (the License);
   8 // you may not use this file except in compliance with the License.
   9 // You may obtain a copy of the License at
  10 //
  11 //     http://floralicense.org/license/
  12 //
  13 // Unless required by applicable law or agreed to in writing, software
  14 // distributed under the License is distributed on an AS IS BASIS,
  15 // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  16 // See the License for the specific language governing permissions and
  17 // limitations under the License.
  18 //
  19
  20 // EXTERNAL INCLUDES
  21 #include <boost/function.hpp>
  22
  23 // INTERNAL INCLUDES
  24 #include <dali/public-api/animation/active-constraint.h>
  25 #include <dali/public-api/animation/alpha-functions.h>
  26 #include <dali/public-api/common/dali-common.h>
  27 #include <dali/internal/event/animation/property-constraint-ptr.h>
  28 #include <dali/internal/update/common/animatable-property.h>
  29 #include <dali/internal/update/common/property-owner.h>
  30 #include <dali/internal/update/animation/scene-graph-constraint-base.h>
  31 #include <dali/internal/render/common/performance-monitor.h>
  32
  33 namespace Dali
  34 {
  35
  36 namespace Internal
  37 {
  38
  39 namespace SceneGraph
  40 {
  41
  42 /**
  43  * Used to constrain a property of a scene-object.
  44  * The constraint function takes another scene-object property as an input.
  45  */
  46 template < class PropertyType, typename PropertyAccessorType >
  47 class Constraint : public ConstraintBase
  48 {
  49 public:
  50
  51   typedef typename PropertyConstraintPtr< PropertyType >::Type ConstraintFunctionPtr;
  52   typedef boost::function< PropertyType (const PropertyType&, const PropertyType&, float progress) > InterpolatorFunc;
  53
  54   /**
  55    * Create a new scene-graph constraint.
  56    * @param[in] targetProperty The target property.
  57    * @param[in] ownerSet A set of property owners; func is connected to the properties provided by these objects.
  58    * @param[in] func The function to calculate the final constrained value.
  59    * @param[in] interpolator The function to interpolate between start & final value.
  60    * @param[in] customWeight A custom weight property, or NULL if the constraint is using its own.
  61    * @return A smart-pointer to a newly allocated constraint.
  62    */
  63   static ConstraintBase* New( const PropertyBase& targetProperty,
  64                               PropertyOwnerSet& ownerSet,
  65                               ConstraintFunctionPtr func,
  66                               InterpolatorFunc interpolator,
  67                               const AnimatableProperty<float>* customWeight )
  68   {
  69     // Scene-graph thread can edit these objects
  70     PropertyBase& property = const_cast< PropertyBase& >( targetProperty );
  71
  72     return new Constraint< PropertyType, PropertyAccessorType >( property,
  73                                                                  ownerSet,
  74                                                                  func,
  75                                                                  interpolator,
  76                                                                  customWeight );
  77   }
  78
  79   /**
  80    * Virtual destructor.
  81    */
  82   virtual ~Constraint()
  83   {
  84   }
  85
  86   /**
  87    * Query whether the constraint needs to be applied. If a constraint depends on a set of properties,
  88    * then it should be applied when any of those properties have changed.
  89    */
  90   bool ApplyNeeded()
  91   {
  92     if ( mFirstApply )
  93     {
  94       mFirstApply = false;
  95       return true;
  96     }
  97
  98     if ( ! mTargetProperty.IsClean() ||
  99            mFunc->InputsChanged()    ||
 100          ! mWeightInput->IsClean() )
 101     {
 102       return true;
 103     }
 104
 105     // We don't need to reapply constraint if none of the properties changed
 106     return false;
 107   }
 108
 109   /**
 110    * @copydoc Dali::Internal::SceneGraph::ConstraintBase::Apply()
 111    */
 112   virtual void Apply( BufferIndex updateBufferIndex )
 113   {
 114     if ( mDisconnected )
 115     {
 116       return; // Early-out when property owners have been disconnected
 117     }
 118
 119     if ( mFunc->InputsInitialized() &&
 120          ApplyNeeded() )
 121     {
 122       const PropertyType& current = mTargetProperty.Get( updateBufferIndex );
 123
 124       // FINAL_WEIGHT means the constraint is fully-applied, unless weight is still being animated
 125       if ( ! mWeightInput->IsClean() ||
 126            ! Equals( Dali::ActiveConstraint::FINAL_WEIGHT, (*mWeightInput)[updateBufferIndex] ) )
 127       {
 128         // Constraint is not fully-applied; interpolation between start & final values
 129         mTargetProperty.Set( updateBufferIndex,
 130                              mInterpolator( current, mFunc->Apply( updateBufferIndex, current ), (*mWeightInput)[updateBufferIndex] ) );
 131       }
 132       else
 133       {
 134         // Constraint is fully-applied; optionally bake the final value
 135         if ( Dali::Constraint::Bake == mRemoveAction )
 136         {
 137           mTargetProperty.Bake( updateBufferIndex, mFunc->Apply( updateBufferIndex, current ) );
 138         }
 139         else
 140         {
 141           mTargetProperty.Set( updateBufferIndex, mFunc->Apply( updateBufferIndex, current ) );
 142         }
 143       }
 144
 145       INCREASE_COUNTER(PerformanceMonitor::CONSTRAINTS_APPLIED);
 146     }
 147     else
 148     {
 149       INCREASE_COUNTER(PerformanceMonitor::CONSTRAINTS_SKIPPED);
 150     }
 151   }
 152
 153 private:
 154
 155   /**
 156    * @copydoc Dali::Internal::SceneGraph::Constraint::New()
 157    */
 158   Constraint( PropertyBase& targetProperty,
 159               PropertyOwnerSet& ownerSet,
 160               ConstraintFunctionPtr func,
 161               InterpolatorFunc interpolator,
 162               const AnimatableProperty<float>* customWeight )
 163   : ConstraintBase( ownerSet ),
 164     mTargetProperty( &targetProperty ),
 165     mFunc( func ),
 166     mInterpolator( interpolator ),
 167     mWeightInput( customWeight ? customWeight : &mWeight)
 168   {
 169   }
 170
 171   // Undefined
 172   Constraint( const Constraint& constraint );
 173
 174   // Undefined
 175   Constraint& operator=( const Constraint& rhs );
 176
 177   /**
 178    * @copydoc Dali::Internal::SceneGraph::ConstraintBase::OnDisconnect()
 179    */
 180   virtual void OnDisconnect()
 181   {
 182     // Discard target object/property pointers
 183     mTargetProperty.Reset();
 184     mFunc = NULL;
 185   }
 186
 187 protected:
 188
 189   PropertyAccessorType mTargetProperty; ///< Raw-pointer to the target property. Not owned.
 190
 191   ConstraintFunctionPtr mFunc;
 192
 193   InterpolatorFunc mInterpolator;
 194
 195   const AnimatableProperty<float>* mWeightInput;
 196 };
 197
 198 } // namespace SceneGraph
 199
 200 } // namespace Internal
 201
 202 } // namespace Dali
 203
 204 #endif // __DALI_INTERNAL_SCENE_GRAPH_CONSTRAINT_H__