examples/image-view-alpha-blending/image-view-alpha-blending-example.cpp

   1 /*
   2  * Copyright (c) 2017 Samsung Electronics Co., Ltd.
   3  *
   4  * Licensed under the Apache License, Version 2.0 (the "License");
   5  * you may not use this file except in compliance with the License.
   6  * You may obtain a copy of the License at
   7  *
   8  * http://www.apache.org/licenses/LICENSE-2.0
   9  *
  10  * Unless required by applicable law or agreed to in writing, software
  11  * distributed under the License is distributed on an "AS IS" BASIS,
  12  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  13  * See the License for the specific language governing permissions and
  14  * limitations under the License.
  15  *
  16  */
  17
  18 #include <dali-toolkit/dali-toolkit.h>
  19
  20 using namespace Dali;
  21
  22 namespace
  23 {
  24 const char* const IMAGE_PATH ( DEMO_IMAGE_DIR "gallery-large-20.jpg" );
  25 }
  26
  27 class ImageViewAlphaBlendApp : public ConnectionTracker
  28 {
  29 public:
  30   ImageViewAlphaBlendApp( Application& application )
  31   : mApplication( application ),
  32     mIndex(0u)
  33   {
  34     // Connect to the Application's Init signal
  35     mApplication.InitSignal().Connect( this, &ImageViewAlphaBlendApp::Create );
  36   }
  37
  38   ~ImageViewAlphaBlendApp()
  39   {
  40     // Nothing to do here;
  41   }
  42
  43 private:
  44   // The Init signal is received once (only) during the Application lifetime
  45   void Create( Application& application )
  46   {
  47     // Get a handle to the stage
  48     Stage stage = Stage::GetCurrent();
  49     stage.KeyEventSignal().Connect(this, &ImageViewAlphaBlendApp::OnKeyEvent);
  50
  51     Vector4 green0 = Vector4( 0.f, 1.f, 0.f, 0.25f );
  52     Vector4 green1 = Vector4( 0.f, 0.25f, 0.f, 0.25f );
  53     BufferImage redGreen0 = CreateBufferImage( Color::RED, green0 );
  54     BufferImage redGreen1 = CreateBufferImage( Color::RED, green1 );
  55     float imageSize = 512.f;
  56
  57     Toolkit::ImageView imageView0 = Toolkit::ImageView::New( IMAGE_PATH );
  58     imageView0.SetSize(imageSize, imageSize);
  59     imageView0.SetParentOrigin( ParentOrigin::CENTER );
  60     imageView0.SetY( -imageSize*0.5f );
  61     stage.Add(imageView0);
  62     Toolkit::ImageView imageView1 = Toolkit::ImageView::New( redGreen0 );
  63     imageView1.SetParentOrigin( ParentOrigin::CENTER );
  64     imageView1.SetSize(imageSize, imageSize);
  65     imageView0.Add(imageView1);
  66
  67     Toolkit::ImageView imageView2 = Toolkit::ImageView::New( IMAGE_PATH );
  68     imageView2.SetSize(imageSize, imageSize);
  69     imageView2.SetParentOrigin( ParentOrigin::CENTER );
  70     imageView2.SetY( imageSize*0.5f );
  71     stage.Add(imageView2);
  72     Toolkit::ImageView imageView3 = Toolkit::ImageView::New( redGreen1);
  73     imageView3.SetParentOrigin( ParentOrigin::CENTER );
  74     imageView3.SetSize(imageSize, imageSize);
  75     imageView2.Add(imageView3);
  76
  77     imageView2.SetProperty( Toolkit::ImageView::Property::PRE_MULTIPLIED_ALPHA, true );
  78     imageView3.SetProperty( Toolkit::ImageView::Property::PRE_MULTIPLIED_ALPHA, true );
  79
  80     Animation animation = Animation::New( 10.f );
  81     animation.AnimateTo(Property(imageView0, Actor::Property::COLOR), Vector4(1.0f, 1.0f, 1.0f, 0.0f), AlphaFunction::BOUNCE, TimePeriod( 2.f, 8.f ));
  82     animation.AnimateTo(Property(imageView2, Actor::Property::COLOR), Vector4(1.0f, 1.0f, 1.0f, 0.0f), AlphaFunction::BOUNCE, TimePeriod( 2.f, 8.f ));
  83     animation.SetLooping( true );
  84     animation.Play();
  85   }
  86
  87   void OnKeyEvent(const KeyEvent& event)
  88   {
  89     if(event.state == KeyEvent::Down)
  90     {
  91       if( IsKey( event, Dali::DALI_KEY_ESCAPE) || IsKey( event, Dali::DALI_KEY_BACK) )
  92       {
  93         mApplication.Quit();
  94       }
  95     }
  96   }
  97
  98   BufferImage CreateBufferImage( const Vector4& color1, const Vector4& color2 )
  99   {
 100     BufferImage image = BufferImage::New( 2, 1, Pixel::RGBA8888 );
 101     PixelBuffer* pixelBuffer = image.GetBuffer();
 102     pixelBuffer[0]=0xFF * color1.x;
 103     pixelBuffer[1]=0xFF * color1.y;
 104     pixelBuffer[2]=0xFF * color1.z;
 105     pixelBuffer[3]=0xFF * color1.w;
 106     pixelBuffer[4]=0xFF * color2.x;
 107     pixelBuffer[5]=0xFF * color2.y;
 108     pixelBuffer[6]=0xFF * color2.z;
 109     pixelBuffer[7]=0xFF * color2.w;
 110     image.Update();
 111     return image;
 112   }
 113
 114
 115 private:
 116   Application&  mApplication;
 117   unsigned int mIndex;
 118 };
 119
 120 int DALI_EXPORT_API main( int argc, char **argv )
 121 {
 122   Application application = Application::New( &argc, &argv );
 123   ImageViewAlphaBlendApp test( application );
 124   application.MainLoop();
 125   return 0;
 126 }