Comment animer la bitmap d’une fenêtre enfant en couches

  • Article

Notes

Pour les applications sur Windows 10, nous vous recommandons d’utiliser les API Windows.UI.Composition au lieu de DirectComposition. Pour plus d’informations, consultez Moderniser votre application de bureau à l’aide de la couche Visual.

Cette rubrique explique comment créer et animer un visuel qui utilise la bitmap d’une fenêtre enfant en couches comme contenu du visuel. L’exemple décrit dans cette rubrique utilise une transformation d’échelle animée pour « augmenter » la bitmap d’une fenêtre enfant de la taille du pouce à la taille réelle. Pour plus d’informations sur les fenêtres en couches, consultez Bitmaps de fenêtre.

Bon à savoir

Technologies

Prérequis

  • C/C++
  • Microsoft Win32
  • COM (Component Object Model)

Instructions

Étape 1 : Créer une fenêtre enfant en couches

Procédez comme suit pour créer une fenêtre enfant en couches.

  1. Inscrivez la classe de fenêtre enfant et créez une fenêtre enfant qui a le style WS_EX_LAYERED . Dans l’exemple suivant, m_dpiX spécifiez m_dpiY la résolution de l’écran en pixels par pouce logique, et m_hwndMain est la poignée de la fenêtre d’application main.
    HWND m_hwndLayeredChild;

    
HRESULT hr = S_OK;

    WNDCLASSEXW wcex;
    wcex.cbSize         = sizeof(wcex);
    wcex.style          = 0;
    wcex.lpfnWndProc    = DemoApp::ChildWndProc;
    wcex.cbClsExtra     = 0;
    wcex.cbWndExtra     = 0;
    wcex.hInstance      = HINST_THISCOMPONENT;
    wcex.hIcon          = NULL;
    wcex.hCursor        = LoadCursor(NULL, IDC_ARROW);
    wcex.hbrBackground  = (HBRUSH) GetStockObject(GRAY_BRUSH);
    wcex.lpszMenuName   = NULL;
    wcex.lpszClassName  = L"DCompLayeredChildWindow";
    wcex.hIconSm        = NULL;

    if (!RegisterClassExW(&wcex))
    {
        return FALSE;
    }

    m_hwndLayeredChild = CreateWindowEx(WS_EX_LAYERED,
        L"DCompLayeredChildWindow",
        NULL,
        WS_CHILD | WS_CLIPSIBLINGS,
        0,
        0,
        static_cast<UINT>(ceil(640.0f * m_dpiX / 96.0f)),
        static_cast<UINT>(ceil(480.0f * m_dpiY / 96.0f)),
        m_hwndMain,
        NULL,
        HINST_THISCOMPONENT,
        this);
  1. Appelez la fonction SetLayeredWindowAttributes pour définir la clé de couleur de transparence et l’opacité de la fenêtre enfant en couches. Le code suivant définit la clé de couleur de transparence sur zéro et l’opacité sur 255 (opaque).
    if (!SetLayeredWindowAttributes(m_hwndLayeredChild, 0, 255, LWA_ALPHA))
    {
        hr = HRESULT_FROM_WIN32(GetLastError());
    }
  1. Affichez du contenu dans la fenêtre enfant.

Étape 2 : Initialiser des objets DirectComposition

Créez l’objet d’appareil et l’objet cible de composition. Pour plus d’informations, consultez Comment initialiser DirectComposition.

Étape 3 : Créer un objet visuel et définir l’image bitmap de la fenêtre enfant en couches comme propriété de contenu

Procédez comme suit pour créer un visuel, définissez sa propriété de contenu pour utiliser l’image bitmap de la fenêtre enfant en couches, puis ajoutez le visuel à l’arborescence visuelle.

  1. Appelez IDCompositionDevice::CreateVisual pour créer un objet visuel.
  2. Créez une surface Microsoft DirectComposition pour la fenêtre enfant en couches en passant le handle de la fenêtre enfant à la fonction CreateSurfaceFromHwnd .
  3. Appelez la méthode IDCompositionVisual::SetContent de l’objet visuel pour définir la nouvelle surface en tant que contenu visuel de la fenêtre enfant en couches.
  4. Ajoutez l’objet visuel à l’arborescence visuelle. Pour ajouter le visuel à la racine de l’arborescence, appelez la méthode IDCompositionTarget::SetRoot . Pour ajouter le visuel en tant qu’enfant d’un autre visuel, utilisez la méthode IDCompositionVisual::AddVisual du visuel parent.

L’exemple suivant crée un objet visuel, définit sa propriété Content pour utiliser l’image bitmap de la fenêtre enfant en couches et ajoute le visuel à la racine de l’arborescence visuelle.

IDCompositionVisual *pVisual = nullptr;
IUnknown* pSurface    = nullptr;

hr = m_pDevice->CreateVisual(&pVisual);
if (SUCCEEDED(hr))
{
    hr = m_pDevice->CreateSurfaceFromHwnd(m_hwndLayeredChild, &pSurface);
}

if (SUCCEEDED(hr))
{
    hr = pVisual->SetContent(pSurface);
}

if (SUCCEEDED(hr))
{
    hr = m_pCompTarget->SetRoot(pVisual);
}

Étape 4 : Créer un objet d’animation et un objet de transformation d’échelle

Utilisez la méthode IDCompositionDevice::CreateAnimation pour créer un objet d’animation et la méthode IDCompositionDevice::CreateScaleTransform pour créer un objet de transformation d’échelle.

IDCompositionAnimation *pAnimateScale = NULL;
IDCompositionScaleTransform *pScale = NULL;

if (SUCCEEDED(hr))
{
    hr = m_pDevice->CreateAnimation(&pAnimateScale);
}

if (SUCCEEDED(hr))
{
    // Create the scale transform object.
    hr = m_pDevice->CreateScaleTransform(&pScale);
}

Étape 5 : Générer la fonction d’animation

Utilisez les méthodes de l’interface IDCompositionAnimation de l’objet d’animation pour générer une fonction d’animation.

L’exemple suivant génère une fonction d’animation simple qui se compose d’un segment polynomial cubique et d’un segment de fin.

pAnimateScale->AddCubic(
    0.0f,  // offset from beginning of animation function, in seconds
    0.0f,  // constant coefficient  
    1.0f,  // linear coefficient
    0.0f,  // quadratic coefficient
    0.0f); // cubic coefficient
pAnimateScale->End(1.0f, 1.0f);

Étape 6 : Appliquer l’objet d’animation aux propriétés de l’objet de transformation d’échelle

Utilisez les méthodes IDCompositionScale::SetScaleX et SetScaleY pour appliquer l’objet d’animation aux propriétés ScaleX et ScaleY de l’objet de transformation d’échelle.

// Find the center of the child window.
RECT rcChild = { };
GetClientRect(m_hwndLayeredChild, &rcChild);
float centerX = rcChild.right / 2.0f;
float centerY = rcChild.bottom / 2.0f;

// Scale from the center point of the child window's bitmap.
pScale->SetCenterX(centerX);
pScale->SetCenterY(centerY);

// Use the same animation object to animate the X and Y scale
// factors.
pScale->SetScaleX(pAnimateScale);
pScale->SetScaleY(pAnimateScale);

Étape 7 : Appliquer l’objet de transformation d’échelle à la propriété transform du visuel

Utilisez la méthode IDCompositionVisual::SetTransform pour appliquer l’objet de transformation d’échelle à la propriété Transform du visuel.

hr = pVisual->SetTransform(pScale);

Étape 8 : cloître la fenêtre enfant en couches

Avant de valider l’animation, utilisez la fonction DwmSetWindowAttribute avec l’indicateur DWMWA_CLOAK pour « cloak » la fenêtre enfant en couches. Le verrouillage supprime la fenêtre enfant en couches de l’affichage pendant que la version animée de l’affichage bitmap de la fenêtre est affichée à l’écran.

BOOL fCloak = TRUE;
DwmSetWindowAttribute(pDemoApp->m_hwndLayeredChild,
    DWMWA_CLOAK,
    &fCloak,
    sizeof(fCloak));

Étape 9 : Valider la composition

Utilisez la méthode IDCompositionDevice::Commit pour valider le lot de commandes sur Microsoft DirectComposition pour traitement. L’animation s’affiche dans la fenêtre cible.

Étape 10 : Déshabillé la fenêtre enfant en couches

Une fois l’animation terminée, utilisez la fonction DwmSetWindowAttribute avec l’indicateur DWMWA_CLOAK pour déshabiler la fenêtre enfant en couches.

Étape 11 : Libérer les objets DirectComposition

Veillez à libérer tous les objets DirectComposition lorsque vous n’en avez plus besoin. L’exemple suivant appelle la macro SafeRelease définie par l’application pour libérer les objets DirectComposition.

SafeRelease(&pVisual);
SafeRelease(&pAnimateScale);
SafeRelease(&pScale);


SafeRelease(&m_pDevice);
SafeRelease(&m_pCompTarget);

Exemple complet

//
// AnimateLayeredChildWindow.h
//
// THIS CODE AND INFORMATION IS PROVIDED "AS IS" WITHOUT WARRANTY OF
// ANY KIND, EITHER EXPRESSED OR IMPLIED, INCLUDING BUT NOT LIMITED TO
// THE IMPLIED WARRANTIES OF MERCHANTABILITY AND/OR FITNESS FOR A
// PARTICULAR PURPOSE.
//
// Copyright (c) Microsoft Corporation. All rights reserved

#pragma once
// Modify the following definitions if you need to target a platform prior to the ones specified below.
#ifndef WINVER              // Allow use of features specific to Windows 7 or later.
#define WINVER 0x0700       // Change this to the appropriate value to target other versions of Windows.
#endif

#ifndef _WIN32_WINNT        // Allow use of features specific to Windows 7 or later.
#define _WIN32_WINNT 0x0700 // Change this to the appropriate value to target other versions of Windows.
#endif

#ifndef UNICODE
#define UNICODE
#endif

#define WIN32_LEAN_AND_MEAN     // Exclude rarely-used items from Windows headers

// Windows Header Files:
#include <windows.h>
#include <wincodec.h>

// C RunTime Header Files
#include <math.h>

// DirectComposition Header File
#include <dcomp.h>

// Direct2D Header Files
#include <d2d1.h>
#include <d2d1helper.h>

// Desktop Window Manager (DWM) Header File
#include <dwmapi.h>


/******************************************************************
*                                                                 *
*  Macros                                                         *
*                                                                 *
******************************************************************/
template<class Interface>
inline void
SafeRelease(
    Interface **ppInterfaceToRelease
    )
{
    if (*ppInterfaceToRelease != NULL)
    {
        (*ppInterfaceToRelease)->Release();

        (*ppInterfaceToRelease) = NULL;
    }
}

#ifndef HINST_THISCOMPONENT
EXTERN_C IMAGE_DOS_HEADER __ImageBase;
#define HINST_THISCOMPONENT ((HINSTANCE)&__ImageBase)
#endif

/******************************************************************
*                                                                 *
*  DemoApp                                                        *
*                                                                 *
******************************************************************/

class DemoApp
{
public:
    DemoApp();
    ~DemoApp();

    HRESULT InitializeMainWindow();
    HRESULT InitializeLayeredChildWindow();

    void RunMessageLoop();

private:
    HRESULT InitializeDirectCompositionObjects();

    HRESULT CreateDeviceIndependentResources();
    HRESULT CreateDeviceResources();
    void DiscardDeviceResources();

    HRESULT OnChildClick();
    HRESULT OnChildRender();

    HRESULT LoadResourceD2DBitmap(
        ID2D1RenderTarget *pRenderTarget,
        IWICImagingFactory *pIWICFactory,
        PCWSTR resourceName,
        PCWSTR resourceType,
        ID2D1Bitmap **ppBitmap
        );

    static LRESULT CALLBACK MainWndProc(
        HWND hWnd,
        UINT message,
        WPARAM wParam,
        LPARAM lParam
        );

    static LRESULT CALLBACK ChildWndProc(
        HWND hWnd,
        UINT message,
        WPARAM wParam,
        LPARAM lParam
        );
    
 private:
    int m_dpiX;
    int m_dpiY;
    int m_childOffsetX;
    int m_childOffsetY;

    HWND m_hwndMain;
    HWND m_hwndLayeredChild;

    IDCompositionDevice *m_pDevice;
    IDCompositionTarget *m_pCompTarget;
    ID2D1HwndRenderTarget *m_pRenderTarget;
    ID2D1Factory *m_pD2DFactory;
    ID2D1Bitmap *m_pBitmap;
    IWICImagingFactory *m_pWICFactory;

 };


//
// AnimateLayeredChildWindow.cpp
//
// THIS CODE AND INFORMATION IS PROVIDED "AS IS" WITHOUT WARRANTY OF
// ANY KIND, EITHER EXPRESSED OR IMPLIED, INCLUDING BUT NOT LIMITED TO
// THE IMPLIED WARRANTIES OF MERCHANTABILITY AND/OR FITNESS FOR A
// PARTICULAR PURPOSE.
//
// Copyright (c) Microsoft Corporation. All rights reserved

// Instructions: Click the thumnail image to animate the transition
//   of the child window from thumbsize to fullsize. Click the child
//   window again to reset.

#include "AnimateLayeredChildWindow.h"

#define TIMER_ID 100

/******************************************************************
*                                                                 *
*  The application entry point.                                   *
*                                                                 *
******************************************************************/

int WINAPI WinMain(
    HINSTANCE   /* hInstance */,
    HINSTANCE   /* hPrevInstance */,
    LPSTR       /* lpCmdLine */,
    int         /* nCmdShow */
    )
{
    // Ignore the return value because we want to run the program even in the
    // unlikely event that HeapSetInformation fails.
    HeapSetInformation(NULL, HeapEnableTerminationOnCorruption, NULL, 0);
    if (SUCCEEDED(CoInitialize(NULL)))
    {
        {
            DemoApp app;

            if (SUCCEEDED(app.InitializeMainWindow()) && SUCCEEDED(app.InitializeLayeredChildWindow()))
            {
                app.RunMessageLoop();
            }
        }
        CoUninitialize();
    }

    return 0;
}

/******************************************************************
*                                                                 *
*  DemoApp::DemoApp constructor                                   *
*                                                                 *
*  Initialize member data.                                        *
*                                                                 *
******************************************************************/

DemoApp::DemoApp() :
    m_dpiX(0),
    m_dpiY(0),
    m_childOffsetX(20),
    m_childOffsetY(40),
    m_hwndMain(NULL),
    m_hwndLayeredChild(NULL),
    m_pDevice(NULL),
    m_pCompTarget(NULL),
    m_pRenderTarget(NULL),
    m_pBitmap(NULL),
    m_pD2DFactory(NULL),
    m_pWICFactory(NULL)
{
}

/******************************************************************
*                                                                 *
*  Release resources.                                             *
*                                                                 *
******************************************************************/

DemoApp::~DemoApp()
{
    SafeRelease(&m_pDevice);
    SafeRelease(&m_pCompTarget);
    SafeRelease(&m_pRenderTarget);
    SafeRelease(&m_pBitmap),
    SafeRelease(&m_pD2DFactory);
    SafeRelease(&m_pWICFactory);
}

/*******************************************************************
*                                                                  *
*  Create the application window.                                  *
*                                                                  *
*******************************************************************/

HRESULT DemoApp::InitializeMainWindow()
{
    HRESULT hr = S_OK;

    // Initialize device-independent resources, such 
    // as the Direct2D factory.
    hr = CreateDeviceIndependentResources();
    if (SUCCEEDED(hr))
    {
        // Register the main window class.
        WNDCLASSEX wcex = { sizeof(WNDCLASSEX) };
        wcex.style         = 0;
        wcex.lpfnWndProc   = DemoApp::MainWndProc;
        wcex.cbClsExtra    = 0;
        wcex.cbWndExtra    = sizeof(LONG_PTR);
        wcex.hInstance     = HINST_THISCOMPONENT;
        wcex.hbrBackground = (HBRUSH)(COLOR_WINDOW + 1);
        wcex.lpszMenuName  = NULL;
        wcex.hCursor       = LoadCursor(NULL, IDC_ARROW);
        wcex.lpszClassName = L"DirectCompDemoApp";

        RegisterClassEx(&wcex);

        RECT rect = { };
        SetRect(&rect, 0, 0, 640, 480);
        AdjustWindowRect(&rect, WS_OVERLAPPED | WS_SYSMENU, FALSE); 

        // Create the main application window.
        //

        // Because the CreateWindow function takes its size in pixels, we
        // obtain the system DPI and use it to scale the window size.
        HDC hdc = GetDC(NULL);
        if (hdc)
        {
            m_dpiX = GetDeviceCaps(hdc, LOGPIXELSX);
            m_dpiY = GetDeviceCaps(hdc, LOGPIXELSY);
            ReleaseDC(NULL, hdc);
        }

        float width = static_cast<float>(rect.right - rect.left);
        float height = static_cast<float>(rect.bottom - rect.top);

        m_hwndMain = CreateWindow(
            L"DirectCompDemoApp",
            L"DirectComposition Demo Application",
            WS_OVERLAPPED | WS_SYSMENU,
            CW_USEDEFAULT,
            CW_USEDEFAULT,
            static_cast<UINT>(ceil(width * m_dpiX / 96.f)),
            static_cast<UINT>(ceil(height * m_dpiY / 96.f)),
            NULL,
            NULL,
            HINST_THISCOMPONENT,
            this
            );
    }

    hr = m_hwndMain ? S_OK : E_FAIL;
    if (SUCCEEDED(hr))
    {
        // Create and initialize the DirectCompositoin objects.
        hr =  InitializeDirectCompositionObjects();
    }

    if (SUCCEEDED(hr))
    {
        ShowWindow(m_hwndMain, SW_SHOWNORMAL);
        UpdateWindow(m_hwndMain);
    }
  
    return hr;
}

/*******************************************************************
*                                                                  *
* Create the layered child window.                                 *
*                                                                  *
/******************************************************************/

HRESULT DemoApp::InitializeLayeredChildWindow()
{
    int thumbWidth = 48;
    int thumbHeight = 32;

    HRESULT hr = S_OK;

    WNDCLASSEXW wcex;
    wcex.cbSize         = sizeof(wcex);
    wcex.style          = 0;
    wcex.lpfnWndProc    = DemoApp::ChildWndProc;
    wcex.cbClsExtra     = 0;
    wcex.cbWndExtra     = 0;
    wcex.hInstance      = HINST_THISCOMPONENT;
    wcex.hIcon          = NULL;
    wcex.hCursor        = LoadCursor(NULL, IDC_ARROW);
    wcex.hbrBackground  = (HBRUSH) GetStockObject (GRAY_BRUSH);
    wcex.lpszMenuName   = NULL;
    wcex.lpszClassName  = L"DCompLayeredChildWindow";
    wcex.hIconSm        = NULL;
    
    if (!RegisterClassExW(&wcex))
    {
        return FALSE;
    }

    m_hwndLayeredChild = CreateWindowEx(WS_EX_LAYERED,
        L"DCompLayeredChildWindow",
        NULL,
        WS_CHILD | WS_CLIPSIBLINGS,
        0,
        0,
        static_cast<UINT>(ceil(640.0f * m_dpiX / 96.0f)),
        static_cast<UINT>(ceil(480.0f * m_dpiY / 96.0f)),
        m_hwndMain,
        NULL,
        HINST_THISCOMPONENT,
        this);

    hr = m_hwndLayeredChild ? S_OK : E_FAIL;
    if (SUCCEEDED(hr))
    {
        // Set the opacity and transparency color key of the layered 
        // child window.
        if (!SetLayeredWindowAttributes(m_hwndLayeredChild, 0, 255, LWA_ALPHA))
        {
            hr = HRESULT_FROM_WIN32(GetLastError());
        }
    }

    if (SUCCEEDED(hr))
    {
        // While the child window is fullsize, load the bitmap resource and
        // render it to the child window.  
        hr = CreateDeviceResources(); 
    }
    
    if (SUCCEEDED(hr))
    {
        // Reduce the window to thumbsize.
        MoveWindow(m_hwndLayeredChild, m_childOffsetX, m_childOffsetY, 
            thumbWidth, thumbHeight, TRUE);
        ShowWindow(m_hwndLayeredChild, SW_SHOWNORMAL);
        UpdateWindow(m_hwndLayeredChild);
    }

    return hr;
}

/******************************************************************
*                                                                 *
*  This method creates the DirectComposition device object and    *
*  and the composition target object. These objects endure for    *
*  the lifetime of the application.                               *
*                                                                 *
******************************************************************/

HRESULT DemoApp::InitializeDirectCompositionObjects()
{
    HRESULT hr = S_OK;

    // Create a DirectComposition device object. 
    hr = DCompositionCreateDevice(nullptr, __uuidof(IDCompositionDevice), 
        reinterpret_cast<void**>(&m_pDevice));

    if (SUCCEEDED(hr))
    {
        // Create the composition target object.
        hr = m_pDevice->CreateTargetForHwnd(m_hwndMain, TRUE, &m_pCompTarget);   
    }

    return hr;
}


/******************************************************************
*                                                                 *
*  This method is used to create resources which are not bound    *
*  to any device. Their lifetime effectively extends for the      *
*  duration of the app.                                           *
*                                                                 *
******************************************************************/

HRESULT DemoApp::CreateDeviceIndependentResources()
{
    HRESULT hr = CoCreateInstance(
        CLSID_WICImagingFactory,
        NULL,
        CLSCTX_INPROC_SERVER,
        IID_PPV_ARGS(&m_pWICFactory)
        );

    if (SUCCEEDED(hr))
    {
        // Create a Direct2D factory.
        hr = D2D1CreateFactory(
            D2D1_FACTORY_TYPE_SINGLE_THREADED,
            &m_pD2DFactory
            );
    }

    return hr;
}

/******************************************************************
*                                                                 *
*  This method creates the D2D bitmap that the application gives  *
*  to DirectComposition to be composed.                           *
*                                                                 *
******************************************************************/

HRESULT DemoApp::CreateDeviceResources()
{
    HRESULT hr = S_OK;

    RECT rc;
    GetClientRect(m_hwndLayeredChild, &rc);

    D2D1_SIZE_U size = D2D1::SizeU(
        rc.right - rc.left,
        rc.bottom - rc.top
        );

    // Create a Direct2D render target.
    hr = m_pD2DFactory->CreateHwndRenderTarget(
        D2D1::RenderTargetProperties(),
        D2D1::HwndRenderTargetProperties(m_hwndLayeredChild, size),
        &m_pRenderTarget
        );

    if (SUCCEEDED(hr))
    {
        hr = LoadResourceD2DBitmap(
            m_pRenderTarget,
            m_pWICFactory,
            L"WhiteFlowers",
            L"Image",
            &m_pBitmap
            );
    }

    return hr;
}

/******************************************************************
*                                                                 *
*  Discard device-specific resources.                             *
*                                                                 *
******************************************************************/

void DemoApp::DiscardDeviceResources()
{
    SafeRelease(&m_pRenderTarget);
    SafeRelease(&m_pBitmap);
}

/******************************************************************
*                                                                 *
*  The main window&#39;s message loop.                                *
*                                                                 *
******************************************************************/

void DemoApp::RunMessageLoop()
{
    MSG msg;

    while (GetMessage(&msg, NULL, 0, 0))
    {
        TranslateMessage(&msg);
        DispatchMessage(&msg);
    }
}

/******************************************************************
*                                                                 *
*  The main window&#39;s message handler.                             *
*                                                                 *
******************************************************************/

LRESULT CALLBACK DemoApp::MainWndProc(HWND hwnd, UINT message, 
    WPARAM wParam, LPARAM lParam)
{
    LRESULT result = 0;

    if (message == WM_CREATE)
    {
        LPCREATESTRUCT pcs = (LPCREATESTRUCT)lParam;
        DemoApp *pDemoApp = (DemoApp *)pcs->lpCreateParams;

        ::SetWindowLongPtrW(
            hwnd,
            GWLP_USERDATA,
            PtrToUlong(pDemoApp)
            );

        result = 1;
    }
    else
    {
        DemoApp *pDemoApp = reinterpret_cast<DemoApp *>(static_cast<LONG_PTR>(
            ::GetWindowLongPtrW(
                hwnd,
                GWLP_USERDATA
                )));

        bool wasHandled = false;

        if (pDemoApp)
        {
            switch (message)
            {
 
            case WM_DISPLAYCHANGE:
                {
                    InvalidateRect(hwnd, NULL, FALSE);
                }
                wasHandled = true;
                result = 0;
                break;

            case WM_DESTROY:
                {
                    PostQuitMessage(0);
                    pDemoApp->DiscardDeviceResources();
                }
                wasHandled = true;
                result = 1;
                break;
            }
        }

        if (!wasHandled)
        {
            result = DefWindowProc(hwnd, message, wParam, lParam);
        }
    }

    return result;
}

/******************************************************************
*                                                                 *
*  The layered child window&#39;s message handler.                    *
*                                                                 *
******************************************************************/

LRESULT CALLBACK DemoApp::ChildWndProc(HWND hwnd, UINT message, 
    WPARAM wParam, LPARAM lParam)
{
    LRESULT result = 0;

    if (message == WM_CREATE)
    {
        LPCREATESTRUCT pcs = (LPCREATESTRUCT)lParam;
        DemoApp *pDemoApp = (DemoApp *)pcs->lpCreateParams;

        ::SetWindowLongPtrW(
            hwnd,
            GWLP_USERDATA,
            PtrToUlong(pDemoApp)
            );

        result = 1;
    }
    else
    {
        DemoApp *pDemoApp = reinterpret_cast<DemoApp *>(static_cast<LONG_PTR>(
            ::GetWindowLongPtrW(
                hwnd,
                GWLP_USERDATA
                )));

        bool wasHandled = false;

        if (pDemoApp)
        {
            switch (message)
            {
            case WM_PAINT:
                {
                    pDemoApp->OnChildRender();
                    ValidateRect(hwnd, NULL);
                }
                wasHandled = true;
                result = 0;
                break;

            case WM_LBUTTONDOWN:
                {
                    HRESULT hr = S_OK;
                    static BOOL fThumbsize = TRUE;

                    // If the child window is already fullsize, reset
                    // the visual tree and return the child window
                    // to thumbsize and move it to its initial location.
                    if (!fThumbsize)
                    {
                        pDemoApp->m_pCompTarget->SetRoot(NULL);
                        hr = pDemoApp->m_pDevice->Commit();  

                        MoveWindow(pDemoApp->m_hwndLayeredChild, 
                            pDemoApp->m_childOffsetX, 
                            pDemoApp->m_childOffsetY, 48, 32, TRUE);

                        pDemoApp->OnChildRender();
                    }   
                    else
                    {
                        // Cloak the child window.
                        BOOL fCloak = TRUE;
                        DwmSetWindowAttribute(pDemoApp->m_hwndLayeredChild,
                            DWMWA_CLOAK,
                            &fCloak,
                            sizeof(fCloak));

                        pDemoApp->OnChildClick();
                    }                    
                    fThumbsize = !fThumbsize;
                }
                wasHandled = true;
                result = 0;
                break;

            case WM_TIMER:
                {
                    // Uncloak the child window.
                    BOOL fCloak = FALSE;
                    DwmSetWindowAttribute(pDemoApp->m_hwndLayeredChild,
                        DWMWA_CLOAK,
                        &fCloak,
                        sizeof(fCloak)); 
                    KillTimer(pDemoApp->m_hwndLayeredChild, TIMER_ID);
                }
                wasHandled = true;
                result = 0;
                break;
            }
        }

        if (!wasHandled)
        {
            result = DefWindowProc(hwnd, message, wParam, lParam);
        }
    }

    return result;
}


/******************************************************************
*                                                                 *
*  Draws a bitmap in the layered child window.                    *
*                                                                 *
******************************************************************/

HRESULT DemoApp::OnChildRender()
{
    HRESULT hr = S_OK;
 
    // Retrieve the size of the render target.
    D2D1_SIZE_F size = m_pRenderTarget->GetSize();
    
    m_pRenderTarget->BeginDraw();
    
    // Draw a bitmap scaled to fill the window.
    m_pRenderTarget->DrawBitmap(
        m_pBitmap,
        D2D1::RectF(0.0f, 0.0f, size.width, size.height)
        );

    hr = m_pRenderTarget->EndDraw();

    if (hr == D2DERR_RECREATE_TARGET)
    {
        hr = S_OK;
        DiscardDeviceResources();
    }

    return hr;
}

/******************************************************************
*                                                                 *
*  Handles a mouse click in the layered child window by animating *
*  the transition from a thumbsize window to a fullsize window.   *
*                                                                 *
******************************************************************/

HRESULT DemoApp::OnChildClick()
{
    int fullWidth = 640;
    int fullHeight = 480;
    HRESULT hr = S_OK;

    IDCompositionVisual *pVisual = nullptr;
    IUnknown* pSurface    = nullptr;

    hr = m_pDevice->CreateVisual(&pVisual);
    if (SUCCEEDED(hr))
    {
        hr = m_pDevice->CreateSurfaceFromHwnd(m_hwndLayeredChild, &pSurface);
    }

    if (SUCCEEDED(hr))
    {
        hr = pVisual->SetContent(pSurface);
    }

    if (SUCCEEDED(hr))
    {
        hr = m_pCompTarget->SetRoot(pVisual);
    }

    if (SUCCEEDED(hr))
    {
       // Position the visual at the same location as the
       // the child window.
        hr = pVisual->SetOffsetX(static_cast<float>(m_childOffsetX));
        if (SUCCEEDED(hr))
        {
            hr = pVisual->SetOffsetY(static_cast<float>(m_childOffsetY));  
        }
    }


    IDCompositionAnimation *pAnimateX = NULL;
    IDCompositionAnimation *pAnimateY = NULL;

    if (SUCCEEDED(hr))
    {
        // Create the animation objects.
        hr = m_pDevice->CreateAnimation(&pAnimateX);
        if (SUCCEEDED(hr))
        {
            hr = m_pDevice->CreateAnimation(&pAnimateY);
        }
    }

    IDCompositionAnimation *pAnimateScale = NULL;
    IDCompositionScaleTransform *pScale = NULL;

    if (SUCCEEDED(hr))
    {
        hr = m_pDevice->CreateAnimation(&pAnimateScale);
    }

    if (SUCCEEDED(hr))
    {
        // Create the scale transform object.
        hr = m_pDevice->CreateScaleTransform(&pScale);
    }

    if (SUCCEEDED(hr))
    {
        // Calculate the X and Y offsets that will position the child window 
        // in the center of the main window&#39;s client area.
        RECT rcParent = { };
        RECT rcChild = { };
        GetClientRect(m_hwndMain, &rcParent);
        GetClientRect(m_hwndLayeredChild, &rcChild);
        float endValX = rcParent.right / 2.0f - rcChild.right / 2.0f;
        float endValY = rcParent.bottom / 2.0f - rcChild.bottom / 2.0f;
 
        // Build the animation functions that will move the visual to the 
        // center of the main window&#39;s client area.
        pAnimateX->AddCubic(0.0f, static_cast<float>(m_childOffsetX), 
            endValX - m_childOffsetX, 0.0f, 0.0f);
        pAnimateX->End(0.9f, endValX);

        pAnimateY->AddCubic(0.0f, static_cast<float>(m_childOffsetY), 
            endValY - m_childOffsetY, 0.0f, 0.0f);
        pAnimateY->End(0.9f, endValY);

        // Associate the animation objects with the offset properties of 
        // the visual.
        hr = pVisual->SetOffsetX(pAnimateX);
        if (SUCCEEDED(hr))
        {
            hr = pVisual->SetOffsetY(pAnimateY);
        }
    }

    if (SUCCEEDED(hr))
    {
        // Commit the visual tree.
        hr = m_pDevice->Commit();  

        // Give the animation a chance to run.
        Sleep(900);
    }

    if (SUCCEEDED(hr))
    {
        // Align the visual with the upper-left corner of the
        // parent window&#39;s client area.
        pVisual->SetOffsetX(0.0);
        pVisual->SetOffsetY(0.0);

        // Enlarge the child window to fill the main window.
        if (!MoveWindow(m_hwndLayeredChild, 0, 0, fullWidth, fullHeight, TRUE))
        {
            hr = HRESULT_FROM_WIN32(GetLastError());
        }
    }

    if (SUCCEEDED(hr))
    {
        // Add animation primitives that define the animation object function 
        // used to scale up the child window&#39;s bitmap.
        pAnimateScale->AddCubic(
            0.0f,  // offset from beginning of animation function, in seconds
            0.0f,  // constant coefficient  
            1.0f,  // linear coefficient
            0.0f,  // quadratic coefficient
            0.0f); // cubic coefficient
        pAnimateScale->End(1.0f, 1.0f);

        // Find the center of the child window.
        RECT rcChild = { };
        GetClientRect(m_hwndLayeredChild, &rcChild);
        float centerX = rcChild.right / 2.0f;
        float centerY = rcChild.bottom / 2.0f;

        // Scale from the center point of the child window&#39;s bitmap.
        pScale->SetCenterX(centerX);
        pScale->SetCenterY(centerY);

        // Use the same animation object to animate the X and Y scale
        // factors.
        pScale->SetScaleX(pAnimateScale);
        pScale->SetScaleY(pAnimateScale);

        // Set the Transform property of the visual to use the scale 
        // transform.
        hr = pVisual->SetTransform(pScale);
    }
    
    if (SUCCEEDED(hr))
    {   // Commit the visual tree.
        hr = m_pDevice->Commit();  

        // Use a WM_TIMER message in the child window procedure 
        // to uncloak the child window. 
        SetTimer(m_hwndLayeredChild, TIMER_ID, 1000, NULL);
    }

    SafeRelease(&pAnimateX);
    SafeRelease(&pAnimateY);
    SafeRelease(&pVisual);
    SafeRelease(&pAnimateScale);
    SafeRelease(&pScale);
    
    return hr;
}


/******************************************************************
*                                                                 *
*  This method will create a Direct2D bitmap from an application  *
*  resource.                                                      *
*                                                                 *
******************************************************************/

HRESULT DemoApp::LoadResourceD2DBitmap(
    ID2D1RenderTarget *pRenderTarget,
    IWICImagingFactory *pIWICFactory,
    PCWSTR resourceName,
    PCWSTR resourceType,
    ID2D1Bitmap **ppBitmap
    )
{
    HRESULT hr = S_OK;
    IWICBitmapDecoder *pDecoder = NULL;
    IWICBitmapFrameDecode *pSource = NULL;
    IWICStream *pStream = NULL;
    IWICFormatConverter *pConverter = NULL;

    HRSRC imageResHandle = NULL;
    HGLOBAL imageResDataHandle = NULL;
    void *pImageFile = NULL;
    DWORD imageFileSize = 0;

    // Locate the resource.
    imageResHandle = FindResourceW(HINST_THISCOMPONENT, resourceName, resourceType);

    hr = imageResHandle ? S_OK : E_FAIL;
    if (SUCCEEDED(hr))
    {
        // Load the resource.
        imageResDataHandle = LoadResource(HINST_THISCOMPONENT, imageResHandle);

        hr = imageResDataHandle ? S_OK : E_FAIL;
    }

    if (SUCCEEDED(hr))
    {
        // Lock it to get a system memory pointer.
        pImageFile = LockResource(imageResDataHandle);

        hr = pImageFile ? S_OK : E_FAIL;
    }

    if (SUCCEEDED(hr))
    {
        // Calculate the size.
        imageFileSize = SizeofResource(HINST_THISCOMPONENT, imageResHandle);

        hr = imageFileSize ? S_OK : E_FAIL;
    }

    if (SUCCEEDED(hr))
    {
        // Create a WIC stream to map onto the memory.
        hr = pIWICFactory->CreateStream(&pStream);
    }

    if (SUCCEEDED(hr))
    {
        // Initialize the stream with the memory pointer and size.
        hr = pStream->InitializeFromMemory(
            reinterpret_cast<BYTE*>(pImageFile),
            imageFileSize
            );
    }

    if (SUCCEEDED(hr))
    {
        // Create a decoder for the stream.
        hr = pIWICFactory->CreateDecoderFromStream(
            pStream,
            NULL,
            WICDecodeMetadataCacheOnLoad,
            &pDecoder
            );
    }

    if (SUCCEEDED(hr))
    {
        // Create the initial frame.
        hr = pDecoder->GetFrame(0, &pSource);
    }

    if (SUCCEEDED(hr))
    {
        // Convert the image format to 32bppPBGRA
        // (DXGI_FORMAT_B8G8R8A8_UNORM + D2D1_ALPHA_MODE_PREMULTIPLIED).
        hr = pIWICFactory->CreateFormatConverter(&pConverter);
    }

    if (SUCCEEDED(hr))
    {
        hr = pConverter->Initialize(
            pSource,
            GUID_WICPixelFormat32bppPBGRA,
            WICBitmapDitherTypeNone,
            NULL,
            0.f,
            WICBitmapPaletteTypeMedianCut
            );
    }

    if (SUCCEEDED(hr))
    {
        // Create a Direct2D bitmap from the WIC bitmap.
        hr = pRenderTarget->CreateBitmapFromWicBitmap(
            pConverter,
            NULL,
            ppBitmap
            );
    }

    SafeRelease(&pDecoder);
    SafeRelease(&pSource);
    SafeRelease(&pStream);
    SafeRelease(&pConverter);

    return hr;
}

Animation

Objets Bitmap

Exemple de fenêtre enfant en couche DirectComposition