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kennykerr/DesktopWindowTarget.cpp

Last active May 27, 2025 09:36
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  1. kennykerr revised this gist Jan 4, 2018. 1 changed file with 3 additions and 14 deletions.
    17 changes: 3 additions & 14 deletions DesktopWindowTarget.cpp
    View file
    Original file line number Diff line number Diff line change
    @@ -3,7 +3,6 @@
    #include <windows.ui.composition.interop.h>
    #include <DispatcherQueue.h>


    extern "C" IMAGE_DOS_HEADER __ImageBase;

    using namespace winrt;
    @@ -105,19 +104,10 @@ struct Window : DesktopWindow<Window>

    LRESULT MessageHandler(UINT const message, WPARAM const wparam, LPARAM const lparam) noexcept
    {
    if (message == WM_CREATE)
    {
    CreateHandler();
    }
    else
    {
    return base_type::MessageHandler(message, wparam, lparam);
    }

    return 0;
    return base_type::MessageHandler(message, wparam, lparam);
    }

    void CreateHandler()
    void PrepareVisuals()
    {
    Compositor compositor;
    m_target = CreateDesktopWindowTarget(compositor, m_window);
    @@ -171,12 +161,11 @@ struct Window : DesktopWindow<Window>

    int __stdcall wWinMain(HINSTANCE, HINSTANCE, LPWSTR, int)
    {
    check_hresult(SetProcessDpiAwareness(PROCESS_PER_MONITOR_DPI_AWARE));
    init_apartment(apartment_type::single_threaded);
    auto controller = CreateDispatcherQueueController();
    auto dispatcher = controller.DispatcherQueue();

    Window window;
    window.PrepareVisuals();
    MSG message;

    while (GetMessage(&message, nullptr, 0, 0))
  2. kennykerr revised this gist Jan 4, 2018. 1 changed file with 0 additions and 1 deletion.
    1 change: 0 additions & 1 deletion DesktopWindowTarget.cpp
    View file
    Original file line number Diff line number Diff line change
    @@ -1,7 +1,6 @@
    #include <winrt/Windows.System.h>
    #include <winrt/Windows.UI.Composition.Desktop.h>
    #include <windows.ui.composition.interop.h>
    #include <ShellScalingAPI.h>
    #include <DispatcherQueue.h>


  3. kennykerr created this gist Jan 4, 2018.
    187 changes: 187 additions & 0 deletions DesktopWindowTarget.cpp
    View file
    Original file line number Diff line number Diff line change
    @@ -0,0 +1,187 @@
    #include <winrt/Windows.System.h>
    #include <winrt/Windows.UI.Composition.Desktop.h>
    #include <windows.ui.composition.interop.h>
    #include <ShellScalingAPI.h>
    #include <DispatcherQueue.h>


    extern "C" IMAGE_DOS_HEADER __ImageBase;

    using namespace winrt;
    using namespace Windows::UI;
    using namespace Windows::UI::Composition;
    using namespace Windows::UI::Composition::Desktop;

    auto CreateDispatcherQueueController()
    {
    namespace ABI = ABI::Windows::System;

    DispatcherQueueOptions options
    {
    sizeof(DispatcherQueueOptions),
    DQTYPE_THREAD_CURRENT,
    DQTAT_COM_STA
    };

    Windows::System::DispatcherQueueController controller{ nullptr };
    check_hresult(CreateDispatcherQueueController(options, reinterpret_cast<ABI::IDispatcherQueueController**>(put_abi(controller))));
    return controller;
    }

    DesktopWindowTarget CreateDesktopWindowTarget(Compositor const& compositor, HWND window)
    {
    namespace ABI = ABI::Windows::UI::Composition::Desktop;

    auto interop = compositor.as<ABI::ICompositorDesktopInterop>();
    DesktopWindowTarget target{ nullptr };
    check_hresult(interop->CreateDesktopWindowTarget(window, true, reinterpret_cast<ABI::IDesktopWindowTarget**>(put_abi(target))));
    return target;
    }

    template <typename T>
    struct DesktopWindow
    {
    using base_type = DesktopWindow<T>;
    HWND m_window = nullptr;

    static T* GetThisFromHandle(HWND const window) noexcept
    {
    return reinterpret_cast<T *>(GetWindowLongPtr(window, GWLP_USERDATA));
    }

    static LRESULT __stdcall WndProc(HWND const window, UINT const message, WPARAM const wparam, LPARAM const lparam) noexcept
    {
    WINRT_ASSERT(window);

    if (WM_NCCREATE == message)
    {
    auto cs = reinterpret_cast<CREATESTRUCT *>(lparam);
    T* that = static_cast<T*>(cs->lpCreateParams);
    WINRT_ASSERT(that);
    WINRT_ASSERT(!that->m_window);
    that->m_window = window;
    SetWindowLongPtr(window, GWLP_USERDATA, reinterpret_cast<LONG_PTR>(that));
    }
    else if (T* that = GetThisFromHandle(window))
    {
    return that->MessageHandler(message, wparam, lparam);
    }

    return DefWindowProc(window, message, wparam, lparam);
    }

    LRESULT MessageHandler(UINT const message, WPARAM const wparam, LPARAM const lparam) noexcept
    {
    if (WM_DESTROY == message)
    {
    PostQuitMessage(0);
    return 0;
    }

    return DefWindowProc(m_window, message, wparam, lparam);
    }
    };

    struct Window : DesktopWindow<Window>
    {
    Window() noexcept
    {
    WNDCLASS wc{};
    wc.hCursor = LoadCursor(nullptr, IDC_ARROW);
    wc.hInstance = reinterpret_cast<HINSTANCE>(&__ImageBase);
    wc.lpszClassName = L"Sample";
    wc.style = CS_HREDRAW | CS_VREDRAW;
    wc.lpfnWndProc = WndProc;
    RegisterClass(&wc);
    WINRT_ASSERT(!m_window);

    WINRT_VERIFY(CreateWindow(wc.lpszClassName,
    L"Sample",
    WS_OVERLAPPEDWINDOW | WS_VISIBLE,
    CW_USEDEFAULT, CW_USEDEFAULT, CW_USEDEFAULT, CW_USEDEFAULT,
    nullptr, nullptr, wc.hInstance, this));

    WINRT_ASSERT(m_window);
    }

    LRESULT MessageHandler(UINT const message, WPARAM const wparam, LPARAM const lparam) noexcept
    {
    if (message == WM_CREATE)
    {
    CreateHandler();
    }
    else
    {
    return base_type::MessageHandler(message, wparam, lparam);
    }

    return 0;
    }

    void CreateHandler()
    {
    Compositor compositor;
    m_target = CreateDesktopWindowTarget(compositor, m_window);
    auto root = compositor.CreateSpriteVisual();
    root.RelativeSizeAdjustment({ 1.0f, 1.0f });
    root.Brush(compositor.CreateColorBrush({ 0xFF, 0xEF, 0xE4 , 0xB0 }));
    m_target.Root(root);
    auto visuals = root.Children();

    AddVisual(visuals, 100.0f, 100.0f);
    AddVisual(visuals, 220.0f, 100.0f);
    AddVisual(visuals, 100.0f, 220.0f);
    AddVisual(visuals, 220.0f, 220.0f);
    }

    void AddVisual(VisualCollection const& visuals, float x, float y)
    {
    auto compositor = visuals.Compositor();
    auto visual = compositor.CreateSpriteVisual();

    static Color colors[] =
    {
    { 0xDC, 0x5B, 0x9B, 0xD5 },
    { 0xDC, 0xFF, 0xC0, 0x00 },
    { 0xDC, 0xED, 0x7D, 0x31 },
    { 0xDC, 0x70, 0xAD, 0x47 },
    };

    static unsigned last = 0;
    unsigned const next = ++last % _countof(colors);
    visual.Brush(compositor.CreateColorBrush(colors[next]));

    visual.Size(
    {
    100.0f,
    100.0f
    });

    visual.Offset(
    {
    x,
    y,
    0.0f,
    });

    visuals.InsertAtTop(visual);
    }

    DesktopWindowTarget m_target{ nullptr };
    };

    int __stdcall wWinMain(HINSTANCE, HINSTANCE, LPWSTR, int)
    {
    check_hresult(SetProcessDpiAwareness(PROCESS_PER_MONITOR_DPI_AWARE));
    init_apartment(apartment_type::single_threaded);
    auto controller = CreateDispatcherQueueController();
    auto dispatcher = controller.DispatcherQueue();

    Window window;
    MSG message;

    while (GetMessage(&message, nullptr, 0, 0))
    {
    DispatchMessage(&message);
    }
    }