Refactor ScreenUtilities

Source/Engine/Platform/Windows/WindowsScreenUtilities.cpp

@@ -0,0 +1,54 @@
+// Copyright (c) 2012-2024 Wojciech Figat. All rights reserved.
+
+#if USE_EDITOR && PLATFORM_WINDOWS
+
+#include "Engine/Platform/Types.h"
+#include "Engine/Platform/ScreenUtilities.h"
+#include "Engine/Core/Math/Vector2.h"
+#include "Engine/Core/Delegate.h"
+#include "Engine/Core/Log.h"
+#include "Engine/Profiler/ProfilerCPU.h"
+
+#include <Windows.h>
+
+#pragma comment(lib, "Gdi32.lib")
+
+Delegate<Color32> ScreenUtilitiesBase::PickColorDone;
+
+static HHOOK MouseCallbackHook;
+
+LRESULT CALLBACK OnScreenUtilsMouseCallback(_In_ int nCode, _In_ WPARAM wParam, _In_ LPARAM lParam)
+{
+    if (nCode >= 0 && wParam == WM_LBUTTONDOWN)
+    {
+        UnhookWindowsHookEx(MouseCallbackHook);
+
+        // Push event with the picked color
+        const Float2 cursorPos = Platform::GetMousePosition();
+        const Color32 colorPicked = ScreenUtilities::GetColorAt(cursorPos);
+        ScreenUtilities::PickColorDone(colorPicked);
+        return 1;
+    }
+    return CallNextHookEx(NULL, nCode, wParam, lParam);
+}
+
+Color32 WindowsScreenUtilities::GetColorAt(const Float2& pos)
+{
+    PROFILE_CPU();
+    HDC deviceContext = GetDC(NULL);
+    COLORREF color = GetPixel(deviceContext, (int)pos.X, (int)pos.Y);
+    ReleaseDC(NULL, deviceContext);
+    return Color32(GetRValue(color), GetGValue(color), GetBValue(color), 255);
+}
+
+void WindowsScreenUtilities::PickColor()
+{
+    MouseCallbackHook = SetWindowsHookEx(WH_MOUSE_LL, OnScreenUtilsMouseCallback, NULL, NULL);
+    if (MouseCallbackHook == NULL)
+    {
+        LOG(Warning, "Failed to set mouse hook.");
+        LOG(Warning, "Error: {0}", GetLastError());
+    }
+}
+
+#endif