Add non-updating mode for Crop-And-Lock

doc/devdocs/modules/cropandlock.md

@@ -20,6 +20,9 @@ Creates a window showing the selected area of the original window. Changes in th
 ### Reparent Mode
 Creates a window that replaces the original window, showing only the selected area. The application is controlled through the cropped window.
 
+### Screenshot Mode
+Creates a window showing a freezed snapshot of the original window. 
+
 ## Code Structure
 
 ### Project Layout
@@ -30,6 +33,7 @@ The Crop and Lock module is part of the PowerToys solution. All the logic-relate
 - **OverlayWindow.cpp**: Thumbnail module type's window concrete implementation.
 - **ReparentCropAndLockWindow.cpp**: Defines the UI for the reparent mode.
 - **ChildWindow.cpp**: Reparent module type's window concrete implementation.
+- **ScreenshotCropAndLockWindow.cpp**: Defines the UI for the screenshot mode.
 
 ## Known Issues
 

src/common/interop/shared_constants.h

@@ -121,6 +121,7 @@ namespace CommonSharedConstants
     // Path to the events used by CropAndLock
     const wchar_t CROP_AND_LOCK_REPARENT_EVENT[] = L"Local\\PowerToysCropAndLockReparentEvent-6060860a-76a1-44e8-8d0e-6355785e9c36";
     const wchar_t CROP_AND_LOCK_THUMBNAIL_EVENT[] = L"Local\\PowerToysCropAndLockThumbnailEvent-1637be50-da72-46b2-9220-b32b206b2434";
+    const wchar_t CROP_AND_LOCK_SCREENSHOT_EVENT[] = L"Local\\PowerToysCropAndLockScreenshotEvent-ff077ab2-8360-4bd1-864a-637389d35593";
     const wchar_t CROP_AND_LOCK_EXIT_EVENT[] = L"Local\\PowerToysCropAndLockExitEvent-d995d409-7b70-482b-bad6-e7c8666f375a";
 
     // Path to the events used by EnvironmentVariables

src/modules/CropAndLock/CropAndLock/CropAndLock.vcxproj

@@ -112,6 +112,7 @@
     <ClCompile Include="ChildWindow.cpp" />
     <ClCompile Include="main.cpp" />
     <ClCompile Include="ReparentCropAndLockWindow.cpp" />
+    <ClCompile Include="ScreenshotCropAndLockWindow.cpp" />
     <ClCompile Include="ThumbnailCropAndLockWindow.cpp" />
     <ClCompile Include="OverlayWindow.cpp" />
     <ClCompile Include="pch.cpp">
@@ -126,6 +127,7 @@
     <ClInclude Include="DisplaysUtil.h" />
     <ClInclude Include="ModuleConstants.h" />
     <ClInclude Include="ReparentCropAndLockWindow.h" />
+    <ClInclude Include="ScreenshotCropAndLockWindow.h" />
     <ClInclude Include="ThumbnailCropAndLockWindow.h" />
     <ClInclude Include="SettingsWindow.h" />
     <ClInclude Include="OverlayWindow.h" />

src/modules/CropAndLock/CropAndLock/CropAndLock.vcxproj.filters

@@ -12,6 +12,7 @@
     <ClCompile Include="ReparentCropAndLockWindow.cpp" />
     <ClCompile Include="ChildWindow.cpp" />
     <ClCompile Include="trace.cpp" />
+    <ClCompile Include="ScreenshotCropAndLockWindow.cpp" />
   </ItemGroup>
   <ItemGroup>
     <ClInclude Include="pch.h" />
@@ -28,6 +29,7 @@
     <ClInclude Include="trace.h" />
     <ClInclude Include="ModuleConstants.h" />
     <ClInclude Include="DispatcherQueue.desktop.interop.h" />
+    <ClInclude Include="ScreenshotCropAndLockWindow.h" />
   </ItemGroup>
   <ItemGroup>
     <ResourceCompile Include="CropAndLock.rc" />

src/modules/CropAndLock/CropAndLock/ScreenshotCropAndLockWindow.cpp

@@ -0,0 +1,181 @@
+#include "pch.h"
+#include "ScreenshotCropAndLockWindow.h"
+
+const std::wstring ScreenshotCropAndLockWindow::ClassName = L"CropAndLock.ScreenshotCropAndLockWindow";
+std::once_flag ScreenshotCropAndLockWindowClassRegistration;
+
+void ScreenshotCropAndLockWindow::RegisterWindowClass()
+{
+    auto instance = winrt::check_pointer(GetModuleHandleW(nullptr));
+    WNDCLASSEXW wcex = {};
+    wcex.cbSize = sizeof(wcex);
+    wcex.style = CS_HREDRAW | CS_VREDRAW;
+    wcex.lpfnWndProc = WndProc;
+    wcex.hInstance = instance;
+    wcex.hIcon = LoadIconW(instance, IDI_APPLICATION);
+    wcex.hCursor = LoadCursorW(nullptr, IDC_ARROW);
+    wcex.hbrBackground = static_cast<HBRUSH>(GetStockObject(BLACK_BRUSH));
+    wcex.lpszClassName = ClassName.c_str();
+    wcex.hIconSm = LoadIconW(wcex.hInstance, IDI_APPLICATION);
+    winrt::check_bool(RegisterClassExW(&wcex));
+}
+
+ScreenshotCropAndLockWindow::ScreenshotCropAndLockWindow(std::wstring const& titleString, int width, int height)
+{
+    auto instance = winrt::check_pointer(GetModuleHandleW(nullptr));
+
+    std::call_once(ScreenshotCropAndLockWindowClassRegistration, []() { RegisterWindowClass(); });
+
+    auto exStyle = 0;
+    auto style = WS_OVERLAPPEDWINDOW | WS_CLIPCHILDREN;
+
+    RECT rect = { 0, 0, width, height };
+    winrt::check_bool(AdjustWindowRectEx(&rect, style, false, exStyle));
+    auto adjustedWidth = rect.right - rect.left;
+    auto adjustedHeight = rect.bottom - rect.top;
+
+    winrt::check_bool(CreateWindowExW(exStyle, ClassName.c_str(), titleString.c_str(), style, CW_USEDEFAULT, CW_USEDEFAULT, adjustedWidth, adjustedHeight, nullptr, nullptr, instance, this));
+    WINRT_ASSERT(m_window);
+}
+
+ScreenshotCropAndLockWindow::~ScreenshotCropAndLockWindow()
+{
+    DestroyWindow(m_window);
+}
+
+LRESULT ScreenshotCropAndLockWindow::MessageHandler(UINT const message, WPARAM const wparam, LPARAM const lparam)
+{
+    switch (message)
+    {
+    case WM_DESTROY:
+        if (m_closedCallback != nullptr && !m_destroyed)
+        {
+            m_destroyed = true;
+            m_closedCallback(m_window);
+        }
+        break;
+    case WM_PAINT:
+        if (m_captured && m_bitmap)
+        {
+            PAINTSTRUCT ps;
+            HDC hdc = BeginPaint(m_window, &ps);
+            HDC memDC = CreateCompatibleDC(hdc);
+            SelectObject(memDC, m_bitmap.get());
+
+            RECT clientRect = {};
+            GetClientRect(m_window, &clientRect);
+            int clientWidth = clientRect.right - clientRect.left;
+            int clientHeight = clientRect.bottom - clientRect.top;
+
+            int srcWidth = m_destRect.right - m_destRect.left;
+            int srcHeight = m_destRect.bottom - m_destRect.top;
+
+            float srcAspect = static_cast<float>(srcWidth) / srcHeight;
+            float dstAspect = static_cast<float>(clientWidth) / clientHeight;
+
+            int drawWidth = clientWidth;
+            int drawHeight = static_cast<int>(clientWidth / srcAspect);
+            if (dstAspect > srcAspect)
+            {
+                drawHeight = clientHeight;
+                drawWidth = static_cast<int>(clientHeight * srcAspect);
+            }
+
+            int offsetX = (clientWidth - drawWidth) / 2;
+            int offsetY = (clientHeight - drawHeight) / 2;
+
+            SetStretchBltMode(hdc, HALFTONE);
+            StretchBlt(hdc, offsetX, offsetY, drawWidth, drawHeight, memDC, 0, 0, srcWidth, srcHeight, SRCCOPY);
+            DeleteDC(memDC);
+            EndPaint(m_window, &ps);
+        }
+        break;
+    default:
+        return base_type::MessageHandler(message, wparam, lparam);
+    }
+    return 0;
+}
+
+void ScreenshotCropAndLockWindow::CropAndLock(HWND windowToCrop, RECT cropRect)
+{
+    if (m_captured)
+    {
+        return;
+    }
+
+    // Get full window bounds
+    RECT windowRect{};
+    winrt::check_hresult(DwmGetWindowAttribute(
+        windowToCrop,
+        DWMWA_EXTENDED_FRAME_BOUNDS,
+        &windowRect,
+        sizeof(windowRect)));
+
+    RECT clientRect = ClientAreaInScreenSpace(windowToCrop);
+    auto offsetX = clientRect.left - windowRect.left;
+    auto offsetY = clientRect.top - windowRect.top;
+
+    m_sourceRect = {
+        cropRect.left + offsetX,
+        cropRect.top + offsetY,
+        cropRect.right + offsetX,
+        cropRect.bottom + offsetY
+    };
+
+    int fullWidth = windowRect.right - windowRect.left;
+    int fullHeight = windowRect.bottom - windowRect.top;
+
+    HDC fullDC = CreateCompatibleDC(nullptr);
+    HBITMAP fullBitmap = CreateCompatibleBitmap(GetDC(nullptr), fullWidth, fullHeight);
+    HGDIOBJ oldFullBitmap = SelectObject(fullDC, fullBitmap);
+
+    // Capture full window
+    winrt::check_bool(PrintWindow(windowToCrop, fullDC, PW_RENDERFULLCONTENT));
+
+
+    // Crop
+    int cropWidth = m_sourceRect.right - m_sourceRect.left;
+    int cropHeight = m_sourceRect.bottom - m_sourceRect.top;
+
+    HDC cropDC = CreateCompatibleDC(nullptr);
+    HBITMAP cropBitmap = CreateCompatibleBitmap(GetDC(nullptr), cropWidth, cropHeight);
+    HGDIOBJ oldCropBitmap = SelectObject(cropDC, cropBitmap);
+
+    BitBlt(
+        cropDC,
+        0,
+        0,
+        cropWidth,
+        cropHeight,
+        fullDC,
+        m_sourceRect.left,
+        m_sourceRect.top,
+        SRCCOPY);
+
+    SelectObject(fullDC, oldFullBitmap);
+    DeleteObject(fullBitmap);
+    DeleteDC(fullDC);
+
+    SelectObject(cropDC, oldCropBitmap);
+    DeleteDC(cropDC);
+    m_bitmap.reset(cropBitmap);
+
+    // Resize our window
+    RECT dest{ 0, 0, cropWidth, cropHeight };
+    LONG_PTR exStyle = GetWindowLongPtrW(m_window, GWL_EXSTYLE);
+    LONG_PTR style = GetWindowLongPtrW(m_window, GWL_STYLE);
+
+    winrt::check_bool(AdjustWindowRectEx(&dest, static_cast<DWORD>(style), FALSE, static_cast<DWORD>(exStyle)));
+
+    winrt::check_bool(SetWindowPos(
+        m_window, HWND_TOPMOST, 0, 0, dest.right - dest.left, dest.bottom - dest.top, SWP_NOMOVE | SWP_SHOWWINDOW));
+
+    m_destRect = { 0, 0, cropWidth, cropHeight };
+    m_captured = true;
+    InvalidateRect(m_window, nullptr, FALSE);
+}
+
+void ScreenshotCropAndLockWindow::Hide()
+{
+    ShowWindow(m_window, SW_HIDE);
+}

src/modules/CropAndLock/CropAndLock/ScreenshotCropAndLockWindow.h

@@ -0,0 +1,29 @@
+#pragma once
+#include <robmikh.common/DesktopWindow.h>
+#include "CropAndLockWindow.h"
+
+struct ScreenshotCropAndLockWindow : robmikh::common::desktop::DesktopWindow<ScreenshotCropAndLockWindow>, CropAndLockWindow
+{
+    static const std::wstring ClassName;
+    ScreenshotCropAndLockWindow(std::wstring const& titleString, int width, int height);
+    ~ScreenshotCropAndLockWindow() override;
+    LRESULT MessageHandler(UINT const message, WPARAM const wparam, LPARAM const lparam);
+
+    HWND Handle() override { return m_window; }
+    void CropAndLock(HWND windowToCrop, RECT cropRect) override;
+    void OnClosed(std::function<void(HWND)> callback) override { m_closedCallback = callback; }
+
+private:
+    static void RegisterWindowClass();
+
+    void Hide();
+
+private:
+    std::unique_ptr<void, decltype(&DeleteObject)> m_bitmap{ nullptr, &DeleteObject };
+    RECT m_destRect = {};
+    RECT m_sourceRect = {};
+
+    bool m_captured = false;
+    bool m_destroyed = false;
+    std::function<void(HWND)> m_closedCallback;
+};

src/modules/CropAndLock/CropAndLock/SettingsWindow.h

@@ -4,4 +4,5 @@ enum class CropAndLockType
 {
 	Reparent,
 	Thumbnail,
+	Screenshot,
 };

src/modules/CropAndLock/CropAndLock/main.cpp

@@ -2,6 +2,7 @@
 #include "SettingsWindow.h"
 #include "OverlayWindow.h"
 #include "CropAndLockWindow.h"
+#include "ScreenshotCropAndLockWindow.h"
 #include "ThumbnailCropAndLockWindow.h"
 #include "ReparentCropAndLockWindow.h"
 #include "ModuleConstants.h"
@@ -133,6 +134,7 @@ int WINAPI wWinMain(_In_ HINSTANCE, _In_opt_ HINSTANCE, _In_ PWSTR lpCmdLine, _I
     // Handles and thread for the events sent from runner
     HANDLE m_reparent_event_handle;
     HANDLE m_thumbnail_event_handle;
+    HANDLE m_screenshot_event_handle;
     HANDLE m_exit_event_handle;
     std::thread m_event_triggers_thread;
 
@@ -181,6 +183,11 @@ int WINAPI wWinMain(_In_ HINSTANCE, _In_opt_ HINSTANCE, _In_ PWSTR lpCmdLine, _I
                 Logger::trace(L"Creating a thumbnail window");
                 Trace::CropAndLock::CreateThumbnailWindow();
                 break;
+            case CropAndLockType::Screenshot:
+                croppedWindow = std::make_shared<ScreenshotCropAndLockWindow>(title, 800, 600);
+                Logger::trace(L"Creating a screenshot window");
+                Trace::CropAndLock::CreateScreenshotWindow();
+                break;
             default:
                 return;
             }
@@ -215,19 +222,20 @@ int WINAPI wWinMain(_In_ HINSTANCE, _In_opt_ HINSTANCE, _In_ PWSTR lpCmdLine, _I
     // Start a thread to listen on the events.
     m_reparent_event_handle = CreateEventW(nullptr, false, false, CommonSharedConstants::CROP_AND_LOCK_REPARENT_EVENT);
     m_thumbnail_event_handle = CreateEventW(nullptr, false, false, CommonSharedConstants::CROP_AND_LOCK_THUMBNAIL_EVENT);
+    m_screenshot_event_handle = CreateEventW(nullptr, false, false, CommonSharedConstants::CROP_AND_LOCK_SCREENSHOT_EVENT);
     m_exit_event_handle = CreateEventW(nullptr, false, false, CommonSharedConstants::CROP_AND_LOCK_EXIT_EVENT);
-    if (!m_reparent_event_handle || !m_thumbnail_event_handle || !m_exit_event_handle)
+    if (!m_reparent_event_handle || !m_thumbnail_event_handle || !m_screenshot_event_handle || !m_exit_event_handle)
     {
         Logger::warn(L"Failed to create events. {}", get_last_error_or_default(GetLastError()));
         return 1;
     }
 
     m_event_triggers_thread = std::thread([&]() {
         MSG msg;
-        HANDLE event_handles[3] = { m_reparent_event_handle, m_thumbnail_event_handle, m_exit_event_handle };
+        HANDLE event_handles[4] = { m_reparent_event_handle, m_thumbnail_event_handle, m_screenshot_event_handle, m_exit_event_handle };
         while (m_running)
         {
-            DWORD dwEvt = MsgWaitForMultipleObjects(3, event_handles, false, INFINITE, QS_ALLINPUT);
+            DWORD dwEvt = MsgWaitForMultipleObjects(4, event_handles, false, INFINITE, QS_ALLINPUT);
             if (!m_running)
             {
                 break;
@@ -259,13 +267,25 @@ int WINAPI wWinMain(_In_ HINSTANCE, _In_opt_ HINSTANCE, _In_ PWSTR lpCmdLine, _I
                 break;
             }
             case WAIT_OBJECT_0 + 2:
+            {
+                // Screenshot Event
+                bool enqueueSucceeded = controller.DispatcherQueue().TryEnqueue([&]() {
+                    ProcessCommand(CropAndLockType::Screenshot);
+                });
+                if (!enqueueSucceeded)
+                {
+                    Logger::error("Couldn't enqueue message to screenshot a window.");
+                }
+                break;
+            }
+            case WAIT_OBJECT_0 + 3:
             {
                 // Exit Event
                 Logger::trace(L"Received an exit event.");
                 PostThreadMessage(mainThreadId, WM_QUIT, 0, 0);
                 break;
             }
-            case WAIT_OBJECT_0 + 3:
+            case WAIT_OBJECT_0 + 4:
                 if (PeekMessageW(&msg, nullptr, 0, 0, PM_REMOVE))
                 {
                     TranslateMessage(&msg);
@@ -295,6 +315,7 @@ int WINAPI wWinMain(_In_ HINSTANCE, _In_opt_ HINSTANCE, _In_ PWSTR lpCmdLine, _I
     SetEvent(m_reparent_event_handle);
     CloseHandle(m_reparent_event_handle);
     CloseHandle(m_thumbnail_event_handle);
+    CloseHandle(m_screenshot_event_handle);
     CloseHandle(m_exit_event_handle);
     m_event_triggers_thread.join();