ImGui Window 未在 DLL 注入中显示

Question

当前目标： 尝试将自定义代码注入 DirectX11 游戏以显示 windows。
预期结果： ImGui 演示 Window 应该在注入后显示，但不应交互
得到的结果： ImGui 演示 Window 在注入时没有显示或显示任何内容。

我尝试过的事情： 制作自定义 Imgui window 并重新注入，调试代码以确保它被运行并被调用每一帧，确保没有任何内容为 NULL，在 google、ImGui GitHub、stack overflow.

上搜索我的问题

D3D11 Init（注入后调用的第一件事）

    LRESULT CALLBACK DXGIMsgProc(HWND hwnd, UINT uMsg, WPARAM wParam, LPARAM lParam) { return DefWindowProc(hwnd, uMsg, wParam, lParam); }
    DWORD __stdcall D3D11Init() {
        // Create Dummy Window
        WNDCLASSEXA wc = { sizeof(WNDCLASSEX), CS_CLASSDC, DXGIMsgProc, 0L, 0L, GetModuleHandleA(NULL), NULL, NULL, NULL, NULL, "DX", NULL };
        RegisterClassExA(&wc);
        HWND hWnd = CreateWindowA("DX", NULL, WS_OVERLAPPEDWINDOW, 100, 100, 300, 300, NULL, NULL, wc.hInstance, NULL);

        D3D_FEATURE_LEVEL levels[] = { D3D_FEATURE_LEVEL_11_0, D3D_FEATURE_LEVEL_10_1 };
        D3D_FEATURE_LEVEL obtainedLevel;
        DXGI_SWAP_CHAIN_DESC sd;
        {
            ZeroMemory(&sd, sizeof(sd));
            sd.BufferCount = 1;
            sd.BufferUsage = DXGI_USAGE_RENDER_TARGET_OUTPUT;
            sd.BufferDesc.Format = DXGI_FORMAT_R8G8B8A8_UNORM;
            sd.OutputWindow = hWnd;
            sd.Windowed = TRUE;
            sd.SwapEffect = DXGI_SWAP_EFFECT_DISCARD;
            sd.SampleDesc.Count = 1;
        }

        HRESULT hr = D3D11CreateDeviceAndSwapChain(nullptr, D3D_DRIVER_TYPE_HARDWARE, nullptr, 0, levels, sizeof(levels) / sizeof(D3D_FEATURE_LEVEL), D3D11_SDK_VERSION, &sd, &d3dSwapChain, &d3dDevice, &obtainedLevel, &d3dContext);
        if (FAILED(hr))
        {
            return E_FAIL;
        }

        pSwapChainVTable = (DWORD_PTR*)(d3dSwapChain);
        pSwapChainVTable = (DWORD_PTR*)(pSwapChainVTable[0]);

        pDeviceVTable = (DWORD_PTR*)(d3dDevice);
        pDeviceVTable = (DWORD_PTR*)pDeviceVTable[0];

        pDeviceContextVTable = (DWORD_PTR*)(d3dContext);
        pDeviceContextVTable = (DWORD_PTR*)(pDeviceContextVTable[0]);

        SAFE_RELEASE(d3dSwapChain);
        SAFE_RELEASE(d3dDevice);
        SAFE_RELEASE(d3dContext);
        UnregisterClassA(wc.lpszClassName, wc.hInstance);

        if (MH_Initialize() != MH_OK) { return 1; }
        if (MH_CreateHook((DWORD_PTR*)pSwapChainVTable[8], PresentHook, reinterpret_cast<void**>(&pHookD3D11Present)) != MH_OK) { return 1; }
        if (MH_EnableHook((DWORD_PTR*)pSwapChainVTable[8]) != MH_OK) { return 1; }

        DWORD old_protect;
        VirtualProtect(pHookD3D11Present, 2, PAGE_EXECUTE_READWRITE, &old_protect);
    }

PresentHook（每次游戏调用Present Function时调用）

    HRESULT __stdcall PresentHook(IDXGISwapChain* pSwapChain, UINT SyncInterval, UINT Flags) {
        if(!init) {
            std::cout << "\t[+] Present Hook called First Time!" << std::endl;
            if (FAILED(GetDeviceAndCtxFromSwapChain(pSwapChain, &d3dDevice, &d3dContext)))
                return pHookD3D11Present(pSwapChain, SyncInterval, Flags);

            // Get Game Window Handle
            DXGI_SWAP_CHAIN_DESC sd;
            pSwapChain->GetDesc(&sd);
            window = sd.OutputWindow;

            ImGui::CreateContext();
            ImGuiIO& io = ImGui::GetIO(); (void) io;
            io.IniFilename = NULL;
            io.ConfigFlags |= ImGuiConfigFlags_NavEnableKeyboard;
            io.DisplaySize = ImVec2(1280, 720);
            
            ImGui_ImplWin32_Init(window);
            ImGui_ImplDX11_Init(d3dDevice, d3dContext);
            init = true;
        };

        ImGui_ImplDX11_NewFrame();
        ImGui_ImplWin32_NewFrame();
        ImGui::NewFrame();
        ImGui::ShowDemoWindow();
        ImGui::EndFrame();
        ImGui::Render();
        ImGui_ImplDX11_RenderDrawData(ImGui::GetDrawData());
        return pHookD3D11Present(pSwapChain, SyncInterval, Flags);
    }

Answer 1

问题是获取当前的 D3D11RenderTargetView 或创建我自己的 D3D11RenderTargetView。添加下面的部分功能或创建一个全新的功能并将其添加到 Present Init 应该可以解决 ImGui 不显示的问题。

bool GetDeivceContextRenderTarget(IDXGISwapChain* pSwapChain)
{
    HRESULT hr = pSwapChain->GetDevice(__uuidof(ID3D11Device), (void**)&pDevice);
    if (FAILED(hr))
        return false;

    pDevice->GetImmediateContext(&pContext);
    pContext->OMSetRenderTargets(1, &pRenderTargetView, nullptr);

    // If for some reason we fail to get a render target, create one
    if (!pRenderTargetView) {
        ID3D11Texture2D* pBackBuffer = nullptr;
        hr = pSwapChain->GetBuffer(0, __uuidof(ID3D11Texture2D), reinterpret_cast<void**>(&pBackBuffer));
        if (FAILED(hr))
            return false;

        hr = pDevice->CreateRenderTargetView(pBackBuffer, nullptr, &pRenderTargetView);
        pBackBuffer->Release();
        if (FAILED(hr))
            return false;

        // Make sure our render target is set, only needed if creating our own, if already exist use original
        pContext->OMSetRenderTargets(1, &pRenderTargetView, nullptr);
    }
    return true;
}

ImGui Window 未在 DLL 注入中显示

ImGui Window doesn't show on DLL Injection

c++

directx

directx-11

imgui