Cómo crear un árbol visual simple
Nota
En el caso de las aplicaciones de Windows 10, se recomienda usar las API de Windows.UI.Composition en lugar de DirectComposition. Para obtener más información, consulta Modernize your desktop app using the Visual layer (Modernización de la aplicación de escritorio mediante la capa visual).
En este tema se muestra cómo crear un árbol visual simple de Microsoft DirectComposition. El ejemplo de este tema crea y compone un árbol visual que consta de un objeto visual raíz y tres objetos visuales secundarios. El contenido del objeto visual raíz es un mapa de bits azul claro que actúa como fondo para los objetos visuales secundarios. En esta ilustración se muestra la composición creada por el código de ejemplo de este tema.
Lo que necesita saber
Tecnologías
Requisitos previos
Conocimiento de:
- C/C++
- Microsoft Win32
- Modelo de objetos componentes (COM)
Instrucciones
Paso 1: Inicializar los objetos de destino de dispositivo y composición
Para obtener más información, vea Cómo inicializar DirectComposition.
Paso 2: Crear los objetos visuales y establecer el contenido del mapa de bits
Use el método IDCompositionDevice::CreateVisual para crear los objetos visuales y el método IDCompositionVisual::SetContent para establecer el contenido de mapa de bits de los objetos visuales.
Nota
En el ejemplo siguiente, el primer elemento de la m_hBitmaps matriz contiene el mapa de bits del objeto visual raíz y los elementos restantes contienen los mapas de bits de los objetos visuales secundarios.
#define NUM_VISUALS 4 // number of visuals in the composition
HBITMAP m_hBitmaps[NUM_VISUALS];
HRESULT hr = S_OK;
IDCompositionVisual *pVisuals[NUM_VISUALS]{ };
IDCompositionSurface *pSurface{ nullptr };
// Create a visual objects and set their content.
for (int i = 0; i < NUM_VISUALS; i++)
{
hr = m_pDevice->CreateVisual(&pVisuals[i]);
if (SUCCEEDED(hr))
{
// This application-defined function creates a DirectComposition
// surface and renders a GDI bitmap onto the surface.
hr = MyCreateGDIRenderedDCompSurface(m_hBitmaps[i], &pSurface);
if (SUCCEEDED(hr))
{
// Set the bitmap content.
hr = pVisuals[i]->SetContent(pSurface);
}
SafeRelease(&pSurface);
}
if (FAILED(hr))
{
goto Cleanup;
}
}
La siguiente función definida por la aplicación muestra cómo crear la superficie Microsoft DirectComposition y representar un mapa de bits de interfaz de dispositivo gráfico (GDI) de Windows en la 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;
POINT pointOffset = { };
hr = hBitmap ? S_OK : E_FAIL;
if (SUCCEEDED(hr))
{
// 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.
hr = m_pDevice->CreateSurface(bitmapWidth, bitmapHeight,
DXGI_FORMAT_B8G8R8A8_UNORM, DXGI_ALPHA_MODE_IGNORE, ppSurface);
}
hr = ppSurface ? S_OK : E_FAIL;
if (SUCCEEDED(hr))
{
hr = (*ppSurface)->BeginDraw(NULL, __uuidof(IDXGISurface1),
reinterpret_cast<void**>(&pDXGISurface), &pointOffset);
}
if (SUCCEEDED(hr))
{
pDXGISurface->GetDC(FALSE, &hSurfaceDC);
}
hr = hSurfaceDC ? S_OK : E_FAIL;
if (SUCCEEDED(hr))
{
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);
}
(*ppSurface)->EndDraw();
SafeRelease(&pDXGISurface);
return hr;
}
Paso 3: Establecer el objeto visual raíz
Establezca los desplazamientos horizontales y verticales del objeto visual raíz y, a continuación, agréguelo al árbol visual llamando al método IDCompositionTarget::SetRoot .
float xPosRoot = 50.0;
float yPosRoot = 50.0;
// Set the horizontal and vertical position of the root visual.
pVisuals[0]->SetOffsetX(xPosRoot);
pVisuals[0]->SetOffsetY(yPosRoot);
// Set the root visual of the visual tree.
hr = m_pCompTarget->SetRoot(pVisuals[0]);
Paso 4: Agregar los objetos visuales secundarios y confirmar la composición
Use métodos expuestos por la interfaz IDCompositionVisual de cada objeto visual secundario para establecer el contenido del mapa de bits y otras propiedades y, a continuación, use el método IDCompositionVisual::AddVisual del objeto visual raíz para agregar los objetos visuales secundarios a la raíz del árbol visual. Llame a IDCompositionDevice::Commit para confirmar el lote de comandos en DirectComposition para su procesamiento. La composición resultante aparece en la ventana de destino.
float xPosChild = 20.0f;
float yPosChild = 20.0f;
if (SUCCEEDED(hr))
{
// Set the positions of the child visuals and add them to the visual tree.
for (int i = 1; i < NUM_VISUALS; i++)
{
pVisuals[i]->SetOffsetX(xPosChild);
pVisuals[i]->SetOffsetY(
static_cast<float>((yPosChild * i) + (CHILD_BITMAP_HEIGHT * (i - 1))));
// Add the child visuals as children of the root visual.
pVisuals[0]->AddVisual(pVisuals[i], TRUE, nullptr);
}
}
// Commit the visual to be composed and displayed.
hr = m_pDevice->Commit();
Paso 5: Liberar los objetos DirectComposition
Libere los objetos visuales en cuanto ya no los necesite. Este siguiente bit de código llama a la macro SafeRelease definida por la aplicación para liberar los objetos visuales.
Cleanup:
// Free the visuals.
for (int i = 0; i < NUM_VISUALS; i++)
{
SafeRelease(&pVisuals[i]);
}
Además, recuerde liberar los objetos de destino del dispositivo y la composición antes de que se cierre la aplicación.
SafeRelease(&m_pD3D11Device);
SafeRelease(&m_pDevice);
SafeRelease(&m_pCompTarget);
Ejemplo completo
// 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>
#include <dcomp.h>
#include <d3d11.h>
/******************************************************************
* *
* Macros *
* *
******************************************************************/
template<class Interface>
inline void
SafeRelease(
Interface **ppInterfaceToRelease
)
{
if (*ppInterfaceToRelease != NULL)
{
(*ppInterfaceToRelease)->Release();
(*ppInterfaceToRelease) = NULL;
}
}
#ifndef Assert
#if defined( DEBUG ) || defined( _DEBUG )
#define Assert(b) if (!(b)) {OutputDebugStringA("Assert: " #b "\n");}
#else
#define Assert(b)
#endif //DEBUG || _DEBUG
#endif
#ifndef HINST_THISCOMPONENT
EXTERN_C IMAGE_DOS_HEADER __ImageBase;
#define HINST_THISCOMPONENT ((HINSTANCE)&__ImageBase)
#endif
// Application-defined constants
#define NUM_VISUALS 4 // number of visuals in the composition
#define CHILD_BITMAP_HEIGHT 96 // height, in pixels, of a child visual
#define NUM_BITMAPS 4 // number of bitmaps in the composition
/******************************************************************
* *
* DemoApp *
* *
******************************************************************/
class DemoApp
{
public:
DemoApp();
~DemoApp();
HRESULT Initialize();
void RunMessageLoop();
private:
HRESULT InitializeDirectCompositionDevice();
HRESULT CreateResources();
void DiscardResources();
HRESULT OnClientClick();
HRESULT DemoApp::LoadResourceGDIBitmap(
PCWSTR resourceName,
HBITMAP &hbmp
);
HRESULT DemoApp::MyCreateGDIRenderedDCompSurface(HBITMAP hBitmap, IDCompositionSurface **ppSurface);
static LRESULT CALLBACK WndProc(
HWND hWnd,
UINT message,
WPARAM wParam,
LPARAM lParam
);
private:
HWND m_hwnd;
HBITMAP m_hBitmaps[NUM_VISUALS];
ID3D11Device *m_pD3D11Device;
IDCompositionDevice *m_pDevice;
IDCompositionTarget *m_pCompTarget;
};
// 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 a root visual and three child
// visuals. The root visual provides the background bitmap for the
// composition, and the three child visuals provide bitmaps that are
// composed on top of the root. All bitmaps are GDI.
#include "SimpleVisualTree.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_hBitmaps(),
m_pD3D11Device(nullptr),
m_pDevice(nullptr),
m_pCompTarget(nullptr)
{
}
/******************************************************************
* *
* Release resources. *
* *
******************************************************************/
DemoApp::~DemoApp()
{
SafeRelease(&m_pD3D11Device);
SafeRelease(&m_pDevice);
SafeRelease(&m_pCompTarget);
}
/*******************************************************************
* *
* 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 = NULL;
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;
IDXGIDevice *pDXGIDevice = nullptr;
// Create the D3D device object.
D3D11CreateDevice(
nullptr,
D3D_DRIVER_TYPE_HARDWARE,
NULL,
D3D11_CREATE_DEVICE_BGRA_SUPPORT,
NULL,
0,
D3D11_SDK_VERSION,
&m_pD3D11Device,
&featureLevelSupported,
NULL);
hr = (m_pD3D11Device == nullptr) ? E_UNEXPECTED : S_OK;
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_pDevice));
}
if (SUCCEEDED(hr))
{
// Create the composition target object.
hr = m_pDevice->CreateTargetForHwnd(m_hwnd, TRUE, &m_pCompTarget);
}
SafeRelease(&pDXGIDevice);
return hr;
}
/******************************************************************
* *
* This method creates the GDI bitmaps to be associated with *
* DirectComposition visual objects. *
* *
******************************************************************/
HRESULT DemoApp::CreateResources()
{
HRESULT hr = S_OK;
hr = LoadResourceGDIBitmap(L"Background", m_hBitmaps[0]);
hr = LoadResourceGDIBitmap(L"BlkKnight", m_hBitmaps[1]);
hr = LoadResourceGDIBitmap(L"BlkQueen", m_hBitmaps[2]);
hr = LoadResourceGDIBitmap(L"BlkRook", m_hBitmaps[3]);
return hr;
}
/******************************************************************
* *
* Discard device-specific resources. *
* *
******************************************************************/
void DemoApp::DiscardResources()
{
int i = 0;
while (i < NUM_VISUALS)
{
DeleteObject(m_hBitmaps[i++]);
}
}
/******************************************************************
* *
* 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 the client area of the main *
* window. This method builds a simple visual tree consisting of *
* a root visual and three child visuals. *
******************************************************************/
HRESULT DemoApp::OnClientClick()
{
HRESULT hr = S_OK;
IDCompositionVisual *pVisuals[NUM_VISUALS] = { };
IDCompositionSurface *pSurface = nullptr;
// Create a visual objects and set their content.
for (int i = 0; i < NUM_VISUALS; i++)
{
hr = m_pDevice->CreateVisual(&pVisuals[i]);
if (SUCCEEDED(hr))
{
// This application-defined function creates a DirectComposition
// surface and renders a GDI bitmap onto the surface.
hr = MyCreateGDIRenderedDCompSurface(m_hBitmaps[i], &pSurface);
if (SUCCEEDED(hr))
{
// Set the bitmap content.
hr = pVisuals[i]->SetContent(pSurface);
}
SafeRelease(&pSurface);
}
if (FAILED(hr))
{
goto Cleanup;
}
}
float xPosRoot = 50.0;
float yPosRoot = 50.0;
// Set the horizontal and vertical position of the root visual.
pVisuals[0]->SetOffsetX(xPosRoot);
pVisuals[0]->SetOffsetY(yPosRoot);
// Set the root visual of the visual tree.
hr = m_pCompTarget->SetRoot(pVisuals[0]);
float xPosChild = 20.0f;
float yPosChild = 20.0f;
if (SUCCEEDED(hr))
{
// Set the positions of the child visuals and add them to the visual tree.
for (int i = 1; i < NUM_VISUALS; i++)
{
pVisuals[i]->SetOffsetX(xPosChild);
pVisuals[i]->SetOffsetY(
static_cast<float>((yPosChild * i) + (CHILD_BITMAP_HEIGHT * (i - 1))));
// Add the child visuals as children of the root visual.
pVisuals[0]->AddVisual(pVisuals[i], TRUE, nullptr);
}
}
// Commit the visual to be composed and displayed.
hr = m_pDevice->Commit();
Cleanup:
// Free the visuals.
for (int i = 0; i < NUM_VISUALS; i++)
{
SafeRelease(&pVisuals[i]);
}
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();
}
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)
{
// Load the bitmap from the application resources.
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;
POINT pointOffset = { };
hr = hBitmap ? S_OK : E_FAIL;
if (SUCCEEDED(hr))
{
// 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.
hr = m_pDevice->CreateSurface(bitmapWidth, bitmapHeight,
DXGI_FORMAT_B8G8R8A8_UNORM, DXGI_ALPHA_MODE_IGNORE, ppSurface);
}
hr = ppSurface ? S_OK : E_FAIL;
if (SUCCEEDED(hr))
{
hr = (*ppSurface)->BeginDraw(NULL, __uuidof(IDXGISurface1),
reinterpret_cast<void**>(&pDXGISurface), &pointOffset);
}
if (SUCCEEDED(hr))
{
pDXGISurface->GetDC(FALSE, &hSurfaceDC);
}
hr = hSurfaceDC ? S_OK : E_FAIL;
if (SUCCEEDED(hr))
{
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);
}
(*ppSurface)->EndDraw();
SafeRelease(&pDXGISurface);
return hr;
}