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

   1 /*
   2  * Copyright (c) 2020 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 #include <dali-toolkit/devel-api/image-loader/texture-manager.h>
  20 #include <dali-toolkit/devel-api/visuals/visual-properties-devel.h>
  21
  22 using namespace Dali;
  23
  24 namespace
  25 {
  26 const char* const IMAGE_PATH(DEMO_IMAGE_DIR "gallery-large-20.jpg");
  27 }
  28
  29 class ImageViewAlphaBlendApp : public ConnectionTracker
  30 {
  31 public:
  32   ImageViewAlphaBlendApp(Application& application)
  33   : mApplication(application),
  34     mIndex(0u)
  35   {
  36     // Connect to the Application's Init signal
  37     mApplication.InitSignal().Connect(this, &ImageViewAlphaBlendApp::Create);
  38   }
  39
  40   ~ImageViewAlphaBlendApp()
  41   {
  42     // Nothing to do here;
  43   }
  44
  45 private:
  46   // The Init signal is received once (only) during the Application lifetime
  47   void Create(Application& application)
  48   {
  49     // Get a handle to the window
  50     Window window = application.GetWindow();
  51     window.KeyEventSignal().Connect(this, &ImageViewAlphaBlendApp::OnKeyEvent);
  52
  53     auto  green0    = Vector4(0.f, 1.f, 0.f, 0.25f);
  54     auto  green1    = Vector4(0.f, 0.25f, 0.f, 0.25f);
  55     auto  redGreen0 = CreateTexture(Color::RED, green0);
  56     auto  redGreen1 = CreateTexture(Color::RED, green1);
  57     float imageSize = 512.f;
  58
  59     Toolkit::ImageView imageView0 = CreateImageView(IMAGE_PATH);
  60     imageView0.SetProperty(Actor::Property::SIZE, Vector2(imageSize, imageSize));
  61     imageView0.SetProperty(Actor::Property::PARENT_ORIGIN, ParentOrigin::CENTER);
  62     imageView0.SetProperty(Actor::Property::POSITION_Y, -imageSize * 0.5f);
  63     window.Add(imageView0);
  64     Toolkit::ImageView imageView1 = CreateImageView(redGreen0);
  65     imageView1.SetProperty(Actor::Property::PARENT_ORIGIN, ParentOrigin::CENTER);
  66     imageView1.SetProperty(Actor::Property::SIZE, Vector2(imageSize, imageSize));
  67     imageView0.Add(imageView1);
  68
  69     Toolkit::ImageView imageView2 = CreateImageView(IMAGE_PATH);
  70     imageView2.SetProperty(Actor::Property::SIZE, Vector2(imageSize, imageSize));
  71     imageView2.SetProperty(Actor::Property::PARENT_ORIGIN, ParentOrigin::CENTER);
  72     imageView2.SetProperty(Actor::Property::POSITION_Y, imageSize * 0.5f);
  73     window.Add(imageView2);
  74     Toolkit::ImageView imageView3 = CreateImageView(redGreen1);
  75     imageView3.SetProperty(Actor::Property::PARENT_ORIGIN, ParentOrigin::CENTER);
  76     imageView3.SetProperty(Actor::Property::SIZE, Vector2(imageSize, imageSize));
  77     imageView2.Add(imageView3);
  78
  79     imageView2.SetProperty(Toolkit::ImageView::Property::PRE_MULTIPLIED_ALPHA, true);
  80     imageView3.SetProperty(Toolkit::ImageView::Property::PRE_MULTIPLIED_ALPHA, true);
  81
  82     Animation animation = Animation::New(10.f);
  83     animation.AnimateTo(Property(imageView0, Actor::Property::COLOR), Vector4(1.0f, 1.0f, 1.0f, 0.0f), AlphaFunction::BOUNCE, TimePeriod(2.f, 8.f));
  84     animation.AnimateTo(Property(imageView2, Actor::Property::COLOR), Vector4(1.0f, 1.0f, 1.0f, 0.0f), AlphaFunction::BOUNCE, TimePeriod(2.f, 8.f));
  85     animation.SetLooping(true);
  86     animation.Play();
  87   }
  88
  89   void OnKeyEvent(const KeyEvent& event)
  90   {
  91     if(event.GetState() == KeyEvent::DOWN)
  92     {
  93       if(IsKey(event, Dali::DALI_KEY_ESCAPE) || IsKey(event, Dali::DALI_KEY_BACK))
  94       {
  95         mApplication.Quit();
  96       }
  97     }
  98   }
  99
 100   std::string CreateTexture(const Vector4& color1, const Vector4& color2)
 101   {
 102     const auto width       = 2u;
 103     const auto height      = 1u;
 104     auto       size        = width * height * 4;
 105     auto       pixelBuffer = new unsigned char[size];
 106     pixelBuffer[0]         = 0xFF * color1.x;
 107     pixelBuffer[1]         = 0xFF * color1.y;
 108     pixelBuffer[2]         = 0xFF * color1.z;
 109     pixelBuffer[3]         = 0xFF * color1.w;
 110     pixelBuffer[4]         = 0xFF * color2.x;
 111     pixelBuffer[5]         = 0xFF * color2.y;
 112     pixelBuffer[6]         = 0xFF * color2.z;
 113     pixelBuffer[7]         = 0xFF * color2.w;
 114
 115     auto pixelData = PixelData::New(pixelBuffer, size, width, height, Pixel::RGBA8888, PixelData::ReleaseFunction::DELETE_ARRAY);
 116     auto texture   = Texture::New(TextureType::TEXTURE_2D, Pixel::RGBA8888, width, height);
 117     texture.Upload(pixelData);
 118
 119     return Toolkit::TextureManager::AddTexture(texture);
 120   }
 121
 122   template<typename TextT>
 123   Toolkit::ImageView CreateImageView(TextT&& filename)
 124   {
 125     auto imageView = Toolkit::ImageView::New();
 126
 127     Property::Map propertyMap;
 128     propertyMap.Insert(Toolkit::ImageVisual::Property::URL, std::forward<TextT>(filename));
 129     propertyMap.Insert(Toolkit::Visual::Property::TYPE, Toolkit::Visual::IMAGE);
 130     propertyMap.Insert(Toolkit::DevelVisual::Property::VISUAL_FITTING_MODE, Toolkit::DevelVisual::FILL);
 131     imageView.SetProperty(Toolkit::ImageView::Property::IMAGE, propertyMap);
 132
 133     return imageView;
 134   }
 135
 136 private:
 137   Application& mApplication;
 138   unsigned int mIndex;
 139 };
 140
 141 int DALI_EXPORT_API main(int argc, char** argv)
 142 {
 143   Application            application = Application::New(&argc, &argv);
 144   ImageViewAlphaBlendApp test(application);
 145   application.MainLoop();
 146   return 0;
 147 }