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) 2019 Samsung Electronics Co., Ltd.
   6  *
   7  * Licensed under the Apache License, Version 2.0 (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://www.apache.org/licenses/LICENSE-2.0
  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
  21 // INTERNAL INCLUDES
  22 #include <dali/public-api/common/dali-common.h>
  23 #include <dali/public-api/signals/callback.h>
  24 #include <dali/internal/event/animation/property-constraint-ptr.h>
  25 #include <dali/internal/update/common/animatable-property.h>
  26 #include <dali/internal/update/common/property-owner.h>
  27 #include <dali/internal/update/animation/scene-graph-constraint-base.h>
  28 #include <dali/internal/render/common/performance-monitor.h>
  29
  30 namespace Dali
  31 {
  32
  33 namespace Internal
  34 {
  35
  36 namespace SceneGraph
  37 {
  38
  39 /**
  40  * Used to constrain a property of a scene-object.
  41  * The constraint function takes another scene-object property as an input.
  42  */
  43 template < class PropertyType, typename PropertyAccessorType >
  44 class Constraint : public ConstraintBase
  45 {
  46 public:
  47
  48   using ConstraintFunctionPtr = typename PropertyConstraintPtr< PropertyType >::Type;
  49
  50   /**
  51    * Create a new scene-graph constraint.
  52    * @param[in] targetProperty The target property.
  53    * @param[in] ownerSet A set of property owners; func is connected to the properties provided by these objects.
  54    * @param[in] func The function to calculate the final constrained value.
  55    * @param[in] removeAction Remove action to perform when constraint is removed
  56    * @return A smart-pointer to a newly allocated constraint.
  57    */
  58   static ConstraintBase* New( const PropertyBase& targetProperty,
  59                               PropertyOwnerContainer& ownerContainer,
  60                               ConstraintFunctionPtr func,
  61                               RemoveAction removeAction )
  62   {
  63     // Scene-graph thread can edit these objects
  64     PropertyBase& property = const_cast< PropertyBase& >( targetProperty );
  65
  66     return new Constraint< PropertyType, PropertyAccessorType >( property,
  67                                                                  ownerContainer,
  68                                                                  func,
  69                                                                  removeAction );
  70   }
  71
  72   /**
  73    * Virtual destructor.
  74    */
  75   ~Constraint() override = default;
  76
  77   /**
  78    * @copydoc Dali::Internal::SceneGraph::ConstraintBase::Apply()
  79    */
  80   void Apply( BufferIndex updateBufferIndex ) override
  81   {
  82     if ( !mDisconnected )
  83     {
  84       if ( mFunc->InputsInitialized() )
  85       {
  86         PropertyType current = mTargetProperty.Get( updateBufferIndex );
  87         mFunc->Apply( updateBufferIndex, current );
  88
  89         // Optionally bake the final value
  90         if ( Dali::Constraint::BAKE == mRemoveAction )
  91         {
  92           mTargetProperty.Bake( updateBufferIndex, current );
  93         }
  94         else
  95         {
  96           mTargetProperty.Set( updateBufferIndex, current );
  97         }
  98
  99         INCREASE_COUNTER(PerformanceMonitor::CONSTRAINTS_APPLIED);
 100       }
 101       else
 102       {
 103         INCREASE_COUNTER(PerformanceMonitor::CONSTRAINTS_SKIPPED);
 104       }
 105     }
 106   }
 107
 108 private:
 109
 110   /**
 111    * @copydoc Dali::Internal::SceneGraph::Constraint::New()
 112    */
 113   Constraint( PropertyBase& targetProperty,
 114               PropertyOwnerContainer& ownerContainer,
 115               ConstraintFunctionPtr func,
 116               RemoveAction removeAction )
 117   : ConstraintBase( ownerContainer, removeAction ),
 118     mTargetProperty( &targetProperty ),
 119     mFunc( func )
 120   {
 121   }
 122
 123   // Undefined
 124   Constraint() = delete;
 125   Constraint( const Constraint& constraint ) = delete;
 126   Constraint& operator=( const Constraint& rhs ) = delete;
 127
 128   /**
 129    * @copydoc Dali::Internal::SceneGraph::ConstraintBase::OnDisconnect()
 130    */
 131   void OnDisconnect() override
 132   {
 133     // Discard target object/property pointers
 134     mTargetProperty.Reset();
 135     mFunc = nullptr;
 136   }
 137
 138 protected:
 139
 140   PropertyAccessorType mTargetProperty; ///< Raw-pointer to the target property. Not owned.
 141
 142   ConstraintFunctionPtr mFunc;
 143
 144 };
 145
 146 } // namespace SceneGraph
 147
 148 } // namespace Internal
 149
 150 } // namespace Dali
 151
 152 #endif // DALI_INTERNAL_SCENE_GRAPH_CONSTRAINT_H