Come inizializzare DirectComposition
Nota
Per le app in Windows 10, è consigliabile usare le API Windows.UI.Composition anziché DirectComposition. Per altre informazioni, vedere Modernizzare l'app desktop usando il livello visuale.
Questo argomento illustra come creare e inizializzare il set minimo di oggetti Microsoft DirectComposition necessari per creare una composizione semplice.
Informazioni importanti
Tecnologie
Prerequisiti
- C/C++
- Microsoft Win32
- Component Object Model (COM)
Istruzioni
Passaggio 1: Creare l'oggetto dispositivo Direct3D
Usare la funzione D3D11CreateDevice dall'API Microsoft Direct3D per creare un'istanza di un oggetto dispositivo che rappresenta la scheda di visualizzazione.
ID3D11Device *m_pD3D11Device;
D3D_FEATURE_LEVEL featureLevelSupported;
// Create the D3D device object. The D3D11_CREATE_DEVICE_BGRA_SUPPORT
// flag enables rendering on surfaces using Direct2D.
hr = D3D11CreateDevice(
nullptr,
D3D_DRIVER_TYPE_HARDWARE,
NULL,
D3D11_CREATE_DEVICE_BGRA_SUPPORT,
NULL,
0,
D3D11_SDK_VERSION,
&m_pD3D11Device,
&featureLevelSupported,
nullptr);
Passaggio 2: Recuperare un puntatore all'oggetto DXGI
Usare il metodo QueryInterface per recuperare il puntatore IDXGIDevice dall'oggetto dispositivo Direct3D. DirectComposition userà l'oggetto Microsoft DirectX Graphics Infrastructure (DXGI) per creare tutti gli oggetti di superficie per il dispositivo DirectComposition.
IDXGIDevice *pDXGIDevice = nullptr;
// Check the result of calling D3D11CreateDriver.
if (SUCCEEDED(hr))
{
// Create the DXGI device used to create bitmap surfaces.
hr = m_pD3D11Device->QueryInterface(&pDXGIDevice);
}
Passaggio 3: Creare l'oggetto dispositivo DirectComposition
Utilizzare la funzione DCompositionCreateDevice per creare un'istanza dell'oggetto dispositivo DirectComposition, specificando il puntatore IDXGIDevice recuperato nel passaggio precedente. La funzione recupera un puntatore IDCompositionDevice usato per creare tutti gli altri oggetti DirectComposition usati in una composizione.
IDCompositionDevice *m_pDCompDevice;
if (SUCCEEDED(hr))
{
// Create the DirectComposition device object.
hr = DCompositionCreateDevice(pDXGIDevice,
__uuidof(IDCompositionDevice),
reinterpret_cast<void **>(&m_pDCompDevice));
}
Passaggio 4: Creare l'oggetto di destinazione della composizione
Usare il metodo IDCompositionDevice::CreateTargetForHwnd per creare un'istanza dell'oggetto di destinazione della composizione. La chiamata a CreateTargetForHwnd associa l'oggetto dispositivo alla finestra dell'applicazione che visualizzerà la composizione.
IDCompositionTarget *m_pDCompTarget;
if (SUCCEEDED(hr))
{
// Create the composition target object based on the
// specified application window.
hr = m_pDCompDevice->CreateTargetForHwnd(m_hwnd, TRUE, &m_pDCompTarget);
}
Passaggio 5: Creare un oggetto visivo
Usare il metodo IDCompositionDevice::CreateVisual per creare un oggetto visivo. Il metodo recupera un puntatore IDCompositionVisual usato per impostare le proprietà dell'oggetto visivo. Per altre informazioni, vedere Proprietà di un oggetto visivo.
IDCompositionVisual *pVisual = nullptr;
// Create a visual object.
hr = m_pDCompDevice->CreateVisual(&pVisual);
Passaggio 6: Creare una superficie di composizione e eseguire il rendering di una bitmap nell'area
Creare un puntatore IDCompositionSurface .
IDCompositionSurface *pSurface = nullptr;
if (SUCCEEDED(hr))
{
// Create a composition surface and render a GDI bitmap
// to the surface.
hr = MyCreateGDIRenderedDCompSurface(m_hBitmap, &pSurface);
}
La funzione seguente crea una superficie Microsoft DirectComposition e disegna la bitmap sulla superficie.
// MyCreateGDIRenderedDCompSurface - Creates a DirectComposition surface and
// copies the bitmap to the surface.
//
// Parameters:
// hBitmap - a GDI bitmap.
// ppSurface - the composition surface object.
//
HRESULT DemoApp::MyCreateGDIRenderedDCompSurface(HBITMAP hBitmap,
IDCompositionSurface **ppSurface)
{
HRESULT hr = S_OK;
int bitmapWidth = 0;
int bitmapHeight = 0;
int bmpSize = 0;
BITMAP bmp = { };
HBITMAP hBitmapOld = NULL;
HDC hSurfaceDC = NULL;
HDC hBitmapDC = NULL;
IDXGISurface1 *pDXGISurface = nullptr;
IDCompositionSurface *pDCSurface = nullptr;
POINT pointOffset = { };
if (ppSurface == nullptr)
return E_INVALIDARG;
// Get information about the bitmap.
bmpSize = GetObject(hBitmap, sizeof(BITMAP), &bmp);
hr = bmpSize ? S_OK : E_FAIL;
if (SUCCEEDED(hr))
{
// Save the bitmap dimensions.
bitmapWidth = bmp.bmWidth;
bitmapHeight = bmp.bmHeight;
// Create a DirectComposition-compatible surface that is the same size
// as the bitmap. The DXGI_FORMAT_B8G8R8A8_UNORM flag is required for
// rendering on the surface using GDI via GetDC.
hr = m_pDCompDevice->CreateSurface(bitmapWidth, bitmapHeight,
DXGI_FORMAT_B8G8R8A8_UNORM, DXGI_ALPHA_MODE_IGNORE, &pDCSurface);
}
if (SUCCEEDED(hr))
{
// Begin rendering to the surface.
hr = pDCSurface->BeginDraw(NULL, __uuidof(IDXGISurface1),
reinterpret_cast<void**>(&pDXGISurface), &pointOffset);
}
if (SUCCEEDED(hr))
{
// Get the device context (DC) for the surface.
hr = pDXGISurface->GetDC(FALSE, &hSurfaceDC);
}
if (SUCCEEDED(hr))
{
// Create a compatible DC and select the surface
// into the DC.
hBitmapDC = CreateCompatibleDC(hSurfaceDC);
if (hBitmapDC != NULL)
{
hBitmapOld = (HBITMAP)SelectObject(hBitmapDC, hBitmap);
BitBlt(hSurfaceDC, pointOffset.x, pointOffset.y,
bitmapWidth, bitmapHeight, hBitmapDC, 0, 0, SRCCOPY);
if (hBitmapOld)
{
SelectObject(hBitmapDC, hBitmapOld);
}
DeleteDC(hBitmapDC);
}
pDXGISurface->ReleaseDC(NULL);
}
// End the rendering.
pDCSurface->EndDraw();
*ppSurface = pDCSurface;
// Call an application-defined macro to free the surface pointer.
SafeRelease(&pDXGISurface);
return hr;
}
Passaggio 7: Associare la superficie all'oggetto visivo e impostare le proprietà dell'oggetto visivo
Chiamare i metodi dell'interfaccia IDCompositionVisual dell'oggetto visivo per impostare le proprietà dell'oggetto visivo.
In questo esempio viene impostato il contenuto bitmap per l'oggetto visivo e la posizione orizzontale e verticale dell'oggetto visivo rispetto all'angolo superiore sinistro del contenitore. Poiché è l'oggetto visivo radice, il contenitore per questo oggetto visivo è la finestra di destinazione della composizione.
if (SUCCEEDED(hr))
{
// Set the bitmap content of the visual.
hr = pVisual->SetContent(pSurface);
}
if (SUCCEEDED(hr))
{
// Set the horizontal and vertical position of the visual relative
// to the upper-left corner of the composition target window.
hr = pVisual->SetOffsetX(xOffset);
if (SUCCEEDED(hr))
{
hr = pVisual->SetOffsetY(yOffset);
}
}
Passaggio 8: Impostare l'oggetto visivo radice dell'albero visivo
Impostare l'oggetto visivo radice dell'albero visivo chiamando il metodo IDCompositionTarget::SetRoot .
if (SUCCEEDED(hr))
{
// Set the visual to be the root of the visual tree.
hr = m_pDCompTarget->SetRoot(pVisual);
}
Passaggio 9: Eseguire il commit della composizione
Chiamare il metodo IDCompositionDevice::Commit per eseguire il commit del batch di comandi in DirectComposition per l'elaborazione. La composizione risultante viene visualizzata nella finestra di destinazione.
if (SUCCEEDED(hr))
{
// Commit the visual to be composed and displayed.
hr = m_pDCompDevice->Commit();
}
Passaggio 10: Liberare gli oggetti DirectComposition
È buona procedura di programmazione liberare tutti gli oggetti visivi non appena non sono più necessari. Nell'esempio seguente viene chiamata la macro SafeRelease definita dall'applicazione per liberare l'oggetto visivo.
// Free the visual.
SafeRelease(&pVisual);
Tenere inoltre presente di liberare l'oggetto DXGI, l'oggetto device e l'oggetto di destinazione della composizione prima dell'uscita dell'applicazione.
SafeRelease(&pDXGIDevice);
SafeRelease(&m_pDCompDevice);
SafeRelease(&m_pDCompTarget);
SafeRelease(&m_pD3D11Device);
Esempio completo
//
// SimpleComposition.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>
// C RunTime Header Files
#include <math.h>
// DirectComposition Header Files
#include <dcomp.h>
// Direct3D Header Files
#include <d3d11.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 Initialize();
void RunMessageLoop();
private:
HRESULT InitializeDirectCompositionDevice();
HRESULT CreateResources();
void DiscardResources();
HRESULT OnClientClick();
HRESULT LoadResourceGDIBitmap(
PCWSTR resourceName,
HBITMAP &hbmp
);
HRESULT MyCreateGDIRenderedDCompSurface(HBITMAP hBitmap,
IDCompositionSurface **ppSurface);
static LRESULT CALLBACK WndProc(
HWND hWnd,
UINT message,
WPARAM wParam,
LPARAM lParam
);
private:
HWND m_hwnd;
HBITMAP m_hBitmap;
ID3D11Device *m_pD3D11Device;
IDCompositionDevice *m_pDCompDevice;
IDCompositionTarget *m_pDCompTarget;
};
//
// SimpleComposition.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: Right-click in the client area to cause DirectCompostion
// to create a simple composition consisting of a single GDI bitmap.
#include "SimpleComposition.h"
/******************************************************************
* *
* 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.Initialize()))
{
app.RunMessageLoop();
}
}
CoUninitialize();
}
return 0;
}
/******************************************************************
* *
* DemoApp::DemoApp constructor *
* *
* Initialize member data. *
* *
******************************************************************/
DemoApp::DemoApp() :
m_hwnd(NULL),
m_hBitmap(NULL),
m_pDCompDevice(nullptr),
m_pDCompTarget(nullptr),
m_pD3D11Device(nullptr)
{
}
/******************************************************************
* *
* Release resources. *
* *
******************************************************************/
DemoApp::~DemoApp()
{
SafeRelease(&m_pDCompDevice);
SafeRelease(&m_pDCompTarget);
SafeRelease(&m_pD3D11Device);
}
/*******************************************************************
* *
* Create the application window. *
* *
*******************************************************************/
HRESULT DemoApp::Initialize()
{
HRESULT hr;
// Register the window class.
WNDCLASSEX wcex = { sizeof(WNDCLASSEX) };
wcex.style = CS_HREDRAW | CS_VREDRAW;
wcex.lpfnWndProc = DemoApp::WndProc;
wcex.cbClsExtra = 0;
wcex.cbWndExtra = sizeof(LONG_PTR);
wcex.hInstance = HINST_THISCOMPONENT;
wcex.hbrBackground = (HBRUSH)(COLOR_WINDOW+1);;
wcex.lpszMenuName = nullptr;
wcex.hCursor = LoadCursor(NULL, IDC_ARROW);
wcex.lpszClassName = L"DirectCompDemoApp";
RegisterClassEx(&wcex);
// Create the application window.
//
// Because the CreateWindow function takes its size in pixels, we
// obtain the system DPI and use it to scale the window size.
int dpiX = 0;
int dpiY = 0;
HDC hdc = GetDC(NULL);
if (hdc)
{
dpiX = GetDeviceCaps(hdc, LOGPIXELSX);
dpiY = GetDeviceCaps(hdc, LOGPIXELSY);
ReleaseDC(NULL, hdc);
}
m_hwnd = CreateWindow(
L"DirectCompDemoApp",
L"DirectComposition Demo Application",
WS_OVERLAPPEDWINDOW,
CW_USEDEFAULT,
CW_USEDEFAULT,
static_cast<UINT>(ceil(640.f * dpiX / 96.f)),
static_cast<UINT>(ceil(480.f * dpiY / 96.f)),
NULL,
NULL,
HINST_THISCOMPONENT,
this
);
hr = m_hwnd ? S_OK : E_FAIL;
if (SUCCEEDED(hr))
{
ShowWindow(m_hwnd, SW_SHOWNORMAL);
UpdateWindow(m_hwnd);
// Initialize DirectComposition resources, such as the
// device object and composition target object.
hr = InitializeDirectCompositionDevice();
}
if (SUCCEEDED(hr))
{
hr = CreateResources();
}
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::InitializeDirectCompositionDevice()
{
HRESULT hr = S_OK;
D3D_FEATURE_LEVEL featureLevelSupported;
// Create the D3D device object. The D3D11_CREATE_DEVICE_BGRA_SUPPORT
// flag enables rendering on surfaces using Direct2D.
hr = D3D11CreateDevice(
nullptr,
D3D_DRIVER_TYPE_HARDWARE,
NULL,
D3D11_CREATE_DEVICE_BGRA_SUPPORT,
NULL,
0,
D3D11_SDK_VERSION,
&m_pD3D11Device,
&featureLevelSupported,
nullptr);
IDXGIDevice *pDXGIDevice = nullptr;
// Check the result of calling D3D11CreateDriver.
if (SUCCEEDED(hr))
{
// Create the DXGI device used to create bitmap surfaces.
hr = m_pD3D11Device->QueryInterface(&pDXGIDevice);
}
if (SUCCEEDED(hr))
{
// Create the DirectComposition device object.
hr = DCompositionCreateDevice(pDXGIDevice,
__uuidof(IDCompositionDevice),
reinterpret_cast<void **>(&m_pDCompDevice));
}
if (SUCCEEDED(hr))
{
// Create the composition target object based on the
// specified application window.
hr = m_pDCompDevice->CreateTargetForHwnd(m_hwnd, TRUE, &m_pDCompTarget);
}
SafeRelease(&pDXGIDevice);
return hr;
}
/******************************************************************
* *
* This method creates the GDI bitmap that the application gives *
* to DirectComposition to be composed. *
* *
******************************************************************/
HRESULT DemoApp::CreateResources()
{
HRESULT hr = S_OK;
hr = LoadResourceGDIBitmap(L"Logo", m_hBitmap);
return hr;
}
/******************************************************************
* *
* Discard device-specific resources. *
* *
******************************************************************/
void DemoApp::DiscardResources()
{
DeleteObject(m_hBitmap);
}
/******************************************************************
* *
* The main window's message loop. *
* *
******************************************************************/
void DemoApp::RunMessageLoop()
{
MSG msg;
while (GetMessage(&msg, NULL, 0, 0))
{
TranslateMessage(&msg);
DispatchMessage(&msg);
}
}
/******************************************************************
* *
* Called whenever the user clicks in client area of the main *
* window. This method builds a simple visual tree and passes it *
* to DirectComposition.
* *
******************************************************************/
HRESULT DemoApp::OnClientClick()
{
HRESULT hr = S_OK;
float xOffset = 20; // horizonal position of visual
float yOffset = 20; // vertical position of visual
IDCompositionVisual *pVisual = nullptr;
// Create a visual object.
hr = m_pDCompDevice->CreateVisual(&pVisual);
IDCompositionSurface *pSurface = nullptr;
if (SUCCEEDED(hr))
{
// Create a composition surface and render a GDI bitmap
// to the surface.
hr = MyCreateGDIRenderedDCompSurface(m_hBitmap, &pSurface);
}
if (SUCCEEDED(hr))
{
// Set the bitmap content of the visual.
hr = pVisual->SetContent(pSurface);
}
if (SUCCEEDED(hr))
{
// Set the horizontal and vertical position of the visual relative
// to the upper-left corner of the composition target window.
hr = pVisual->SetOffsetX(xOffset);
if (SUCCEEDED(hr))
{
hr = pVisual->SetOffsetY(yOffset);
}
}
if (SUCCEEDED(hr))
{
// Set the visual to be the root of the visual tree.
hr = m_pDCompTarget->SetRoot(pVisual);
}
if (SUCCEEDED(hr))
{
// Commit the visual to be composed and displayed.
hr = m_pDCompDevice->Commit();
}
// Free the visual.
SafeRelease(&pVisual);
return hr;
}
/******************************************************************
* *
* The window's message handler. *
* *
******************************************************************/
LRESULT CALLBACK DemoApp::WndProc(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_LBUTTONDOWN:
{
pDemoApp->OnClientClick();
}
wasHandled = true;
result = 0;
break;
case WM_DISPLAYCHANGE:
{
InvalidateRect(hwnd, NULL, FALSE);
}
wasHandled = true;
result = 0;
break;
case WM_DESTROY:
{
PostQuitMessage(0);
pDemoApp->DiscardResources();
}
wasHandled = true;
result = 1;
break;
}
}
if (!wasHandled)
{
result = DefWindowProc(hwnd, message, wParam, lParam);
}
}
return result;
}
/******************************************************************
* *
* This method loads the specified GDI bitmap from the *
* application resources, creates a new bitmap that is in a *
* format that DirectComposition can use, and copies the contents *
* of the original bitmap to the new bitmap. *
* *
******************************************************************/
HRESULT DemoApp::LoadResourceGDIBitmap(PCWSTR resourceName, HBITMAP &hbmp)
{
hbmp = static_cast<HBITMAP>(LoadImageW(HINST_THISCOMPONENT, resourceName,
IMAGE_BITMAP, 0, 0, LR_DEFAULTCOLOR));
return hbmp ? S_OK : E_FAIL;
}
// MyCreateGDIRenderedDCompSurface - Creates a DirectComposition surface and
// copies the bitmap to the surface.
//
// Parameters:
// hBitmap - a GDI bitmap.
// ppSurface - the composition surface object.
//
HRESULT DemoApp::MyCreateGDIRenderedDCompSurface(HBITMAP hBitmap,
IDCompositionSurface **ppSurface)
{
HRESULT hr = S_OK;
int bitmapWidth = 0;
int bitmapHeight = 0;
int bmpSize = 0;
BITMAP bmp = { };
HBITMAP hBitmapOld = NULL;
HDC hSurfaceDC = NULL;
HDC hBitmapDC = NULL;
IDXGISurface1 *pDXGISurface = nullptr;
IDCompositionSurface *pDCSurface = nullptr;
POINT pointOffset = { };
if (ppSurface == nullptr)
return E_INVALIDARG;
// Get information about the bitmap.
bmpSize = GetObject(hBitmap, sizeof(BITMAP), &bmp);
hr = bmpSize ? S_OK : E_FAIL;
if (SUCCEEDED(hr))
{
// Save the bitmap dimensions.
bitmapWidth = bmp.bmWidth;
bitmapHeight = bmp.bmHeight;
// Create a DirectComposition-compatible surface that is the same size
// as the bitmap. The DXGI_FORMAT_B8G8R8A8_UNORM flag is required for
// rendering on the surface using GDI via GetDC.
hr = m_pDCompDevice->CreateSurface(bitmapWidth, bitmapHeight,
DXGI_FORMAT_B8G8R8A8_UNORM, DXGI_ALPHA_MODE_IGNORE, &pDCSurface);
}
if (SUCCEEDED(hr))
{
// Begin rendering to the surface.
hr = pDCSurface->BeginDraw(NULL, __uuidof(IDXGISurface1),
reinterpret_cast<void**>(&pDXGISurface), &pointOffset);
}
if (SUCCEEDED(hr))
{
// Get the device context (DC) for the surface.
hr = pDXGISurface->GetDC(FALSE, &hSurfaceDC);
}
if (SUCCEEDED(hr))
{
// Create a compatible DC and select the surface
// into the DC.
hBitmapDC = CreateCompatibleDC(hSurfaceDC);
if (hBitmapDC != NULL)
{
hBitmapOld = (HBITMAP)SelectObject(hBitmapDC, hBitmap);
BitBlt(hSurfaceDC, pointOffset.x, pointOffset.y,
bitmapWidth, bitmapHeight, hBitmapDC, 0, 0, SRCCOPY);
if (hBitmapOld)
{
SelectObject(hBitmapDC, hBitmapOld);
}
DeleteDC(hBitmapDC);
}
pDXGISurface->ReleaseDC(NULL);
}
// End the rendering.
pDCSurface->EndDraw();
*ppSurface = pDCSurface;
// Call an application-defined macro to free the surface pointer.
SafeRelease(&pDXGISurface);
return hr;
}
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