“访问冲突读取位置”使从directx检索缓冲区变得麻烦

时间:2010-04-27 13:43:26

标签: c++ c visual-studio directx

我遇到的问题是以下

ID3D10Texture2D *pBackBuffer;

hr = mpSwapChain->GetBuffer(0, __uuidof(ID3D10Texture2D), (LPVOID*) &pBackBuffer);

以下是我的代码......

#include "DX3dApp.h"




bool DX3dApp::Init(HINSTANCE hInstance, int width, int height)
{
    mhInst = hInstance;
    mWidth = width;
    mHeight = height;

    if(!WindowsInit())
    {
        return false;
    }
    if(!InitDirect3D())
    {
        return false;
    }

    return true;
}

int DX3dApp::Run()
{
     MSG msg = {0};

     while (WM_QUIT != msg.message)
    {
        while (PeekMessage(&msg, NULL, 0, 0, PM_REMOVE) == TRUE)
        {
            TranslateMessage(&msg);
            DispatchMessage(&msg);
        }

        Render();
    }

    return (int) msg.wParam;
}

bool DX3dApp::WindowsInit()
{
    WNDCLASSEX wcex;

    wcex.cbSize = sizeof(WNDCLASSEX);
    wcex.style          = CS_HREDRAW | CS_VREDRAW;
    wcex.lpfnWndProc    = (WNDPROC)WndProc;
    wcex.cbClsExtra     = 0;
    wcex.cbWndExtra     = 0;
    wcex.hInstance      = mhInst;
    wcex.hIcon          = 0;
    wcex.hCursor        = LoadCursor(NULL, IDC_ARROW);
    wcex.hbrBackground  = (HBRUSH)(COLOR_WINDOW+1);
    wcex.lpszMenuName   = NULL;
    wcex.lpszClassName  = TEXT("DirectXExample");
    wcex.hIconSm        = 0;
    RegisterClassEx(&wcex);

    // Resize the window
    RECT rect = { 0, 0, mWidth, mHeight };
    AdjustWindowRect(&rect, WS_OVERLAPPEDWINDOW, FALSE);

    // create the window from the class above
    mMainhWnd = CreateWindow(TEXT("DirectXExample"), 
                             TEXT("DirectXExample"), 
                             WS_OVERLAPPEDWINDOW,
                             CW_USEDEFAULT, 
                             CW_USEDEFAULT, 
                             rect.right - rect.left, 
                             rect.bottom - rect.top, 
                             NULL, 
                             NULL, 
                             mhInst, 
                             NULL);
   if (!mMainhWnd)
   {
      return false;
   }

   ShowWindow(mMainhWnd, SW_SHOW);
   UpdateWindow(mMainhWnd);

   return true;
}

bool DX3dApp::InitDirect3D()
{
    DXGI_SWAP_CHAIN_DESC scd;
    ZeroMemory(&scd, sizeof(scd));

    scd.BufferCount = 1;
    scd.BufferDesc.Width = mWidth;
    scd.BufferDesc.Height = mHeight;
    scd.BufferDesc.Format = DXGI_FORMAT_B8G8R8A8_UNORM;
    scd.BufferDesc.RefreshRate.Numerator = 60;
    scd.BufferDesc.RefreshRate.Denominator = 1;
    scd.BufferUsage = DXGI_USAGE_RENDER_TARGET_OUTPUT;
    scd.OutputWindow = mMainhWnd;
    scd.SampleDesc.Count = 1;
    scd.SampleDesc.Quality = 0;
    scd.Windowed = TRUE;

    HRESULT hr = D3D10CreateDeviceAndSwapChain(NULL,D3D10_DRIVER_TYPE_REFERENCE,
                                                NULL,
                                                0,
                                                D3D10_SDK_VERSION,
                                                &scd,
                                                &mpSwapChain,
                                                &mpD3DDevice);

    if(!hr != S_OK)
    {
        return FALSE;
    }

    ID3D10Texture2D *pBackBuffer;

    hr = mpSwapChain->GetBuffer(0, __uuidof(ID3D10Texture2D), (LPVOID*) &pBackBuffer);

    return TRUE;
}

void DX3dApp::Render()
{

}


LRESULT CALLBACK WndProc(HWND hWnd, UINT message, WPARAM wParam, LPARAM lParam)
{
    switch (message) 
    {
        // Allow the user to press the escape key to end the application
        case WM_KEYDOWN:
            switch(wParam)
            {
                // Check if the user hit the escape key
                case VK_ESCAPE:
                    PostQuitMessage(0);
                break;
            }
        break;

        // The user hit the close button, close the application
        case WM_DESTROY:
            PostQuitMessage(0);
        break;
    }
    return DefWindowProc(hWnd, message, wParam, lParam);
}

我收到以下错误

chp1.exe': Unloaded 'C:\Windows\SysWOW64\oleaut32.dll'
First-chance exception at 0x757ce124 in chp1.exe: Microsoft C++ exception: _com_error at memory location 0x0018eeb0..
First-chance exception at 0x757ce124 in chp1.exe: Microsoft C++ exception: _com_error at memory location 0x0018edd0..
First-chance exception at 0x757ce124 in chp1.exe: Microsoft C++ exception: _com_error at memory location 0x0018ef1c..
The thread 'Win32 Thread' (0xfc4) has exited with code 0 (0x0).
'chp1.exe': Unloaded 'C:\Windows\SysWOW64\D3D10Ref.DLL'
First-chance exception at 0x00b71894 in chp1.exe: 0xC0000005: Access violation reading location 0x00000000.
Unhandled exception at 0x00b71894 in chp1.exe: 0xC0000005: Access violation reading location 0x00000000.

似乎错误发生在最后一个参数中。 &安培; pBackBuffer。我添加了这一行代码并发生错误。

[编辑]

如下所述,问题是我正在访问一个指向缓冲区的空指针。但是我不知道创造它我做错了什么。

2 个答案:

答案 0 :(得分:3)

此错误表示您访问了NULL指针。最有可能的是,mpSwapChain为NULL。

修改

您对hr的检查未正确执行:它应为if (hr != S_OK)而不是if (!hr != S_OK)

检查hr的更好方法是:if (FAILED(hr))(或检查成功时为SUCCEEDED(hr))。这样做会更好,因为hr的某些成功值不是S_OK

答案 1 :(得分:1)

找出我的问题。问题是以下代码行

scd.BufferDesc.Format = DXGI_FORMAT_B8G8R8A8_UNORM;

我输入的缓冲区格式不正确。这几乎类似于

scd.BufferDesc.Format = DXGI_FORMAT_R8G8B8A8_UNORM;

所以喜欢interjay说。当这样的错误组成时。更可能是它的问题导致SwapChain不被启动。这更可能是一个逻辑错误。