Windows屏幕水印-Python和C++实现

已测试平台:

• Windows11

开发环境:

• Python
  • Python 3.10.13
  • Pyside6==6.9.0
• C/C++
  • Platform v143
  • C++ 14
  • MSVC
  • WinSDK 10.0

Python Pyside6实现:

import sys
from PySide6.QtWidgets import QApplication, QWidget
from PySide6.QtCore import Qt, QTimer
from PySide6.QtGui import QPainter, QColor, QFont, QGuiApplication


class WatermarkWindow(QWidget):
    def __init__(self, screen_geometry, text="Test", opacity=0.1, spacing=400):
        super().__init__()
        self.text = text
        self.opacity = opacity
        self.spacing = spacing
        self.setGeometry(screen_geometry)

        self.setWindowFlags(
            Qt.WindowStaysOnTopHint |
            Qt.FramelessWindowHint |
            Qt.Tool
        )
        self.setAttribute(Qt.WA_TranslucentBackground)
        self.setAttribute(Qt.WA_TransparentForMouseEvents)

        self.timer = QTimer(self)
        self.timer.timeout.connect(self.update)
        self.timer.start(2000)

    def paintEvent(self, event):
        painter = QPainter(self)
        painter.setRenderHint(QPainter.Antialiasing)
        painter.setOpacity(self.opacity)

        color = QColor(255, 0, 0)
        color.setAlphaF(self.opacity)
        painter.setPen(color)
        painter.setFont(QFont("Arial", int(self.spacing / 10), QFont.Bold))

        spacing = self.spacing
        for y in range(0, self.height(), spacing):
            for x in range(0, self.width(), spacing):
                painter.save()
                painter.translate(x, y)
                painter.rotate(-30)
                painter.drawText(0, 0, self.text)
                painter.restore()


def create_watermarks_on_all_screens(text="Test", opacity=0.15, spacing=400):
    watermarks = []
    for screen in QGuiApplication.screens():
        geo = screen.geometry()
        wm = WatermarkWindow(screen_geometry=geo, text=text, opacity=opacity, spacing=spacing)
        wm.show()
        watermarks.append(wm)
    return watermarks


if __name__ == "__main__":
    app = QApplication(sys.argv)
    watermark_windows = create_watermarks_on_all_screens("屏幕水印测试", opacity=0.35, spacing=200)
    sys.exit(app.exec())

C++ 实现：

#include <windows.h>
#include <gdiplus.h>
#include <string>
#include <vector>
#include <Lmcons.h>

#pragma comment(lib, "gdiplus.lib")

using namespace Gdiplus;

const wchar_t CLASS_NAME[] = L"WatermarkLayeredGDIPlus";

std::wstring watermarkText;

int spacing = 300;
int fontSize = 30;
BYTE textAlpha = 200;

LRESULT CALLBACK WndProc(HWND hwnd, UINT msg, WPARAM wParam, LPARAM lParam) {
    if (msg == WM_DESTROY)
        PostQuitMessage(0);
    return DefWindowProc(hwnd, msg, wParam, lParam);
}

void DrawWatermark(HWND hwnd, int width, int height) {
    HDC hdcScreen = GetDC(nullptr);
    HDC hdcMem = CreateCompatibleDC(hdcScreen);

    BITMAPINFO bmi = { 0 };
    bmi.bmiHeader.biSize = sizeof(BITMAPINFOHEADER);
    bmi.bmiHeader.biWidth = width;
    bmi.bmiHeader.biHeight = -height;
    bmi.bmiHeader.biPlanes = 1;
    bmi.bmiHeader.biBitCount = 32;
    bmi.bmiHeader.biCompression = BI_RGB;

    void* pvBits = nullptr;
    HBITMAP hBitmap = CreateDIBSection(hdcScreen, &bmi, DIB_RGB_COLORS, &pvBits, nullptr, 0);
    HGDIOBJ oldBitmap = SelectObject(hdcMem, hBitmap);

    Graphics graphics(hdcMem);
    graphics.SetSmoothingMode(SmoothingModeHighQuality);
    graphics.Clear(Color(0, 0, 0, 0));

    FontFamily fontFamily(L"Arial");
    Font font(&fontFamily, (REAL)fontSize, FontStyleBold, UnitPixel);

    SolidBrush textBrush(Color(180, 255, 0, 0)); // 半透明红色

    StringFormat format;
    format.SetAlignment(StringAlignmentCenter);
    format.SetLineAlignment(StringAlignmentCenter);

    for (int y = 0; y < height; y += spacing) {
        for (int x = 0; x < width; x += spacing) {
            graphics.ResetTransform();
            graphics.TranslateTransform((REAL)x + spacing / 2, (REAL)y + spacing / 2);
            graphics.RotateTransform(-30);
            graphics.DrawString(watermarkText.c_str(), -1, &font,
                PointF(0, 0), &format, &textBrush);
        }
    }

    POINT ptPos = { 0, 0 };
    SIZE sizeWnd = { width, height };
    POINT ptSrc = { 0, 0 };

    BLENDFUNCTION blend = {};
    blend.BlendOp = AC_SRC_OVER;
    blend.BlendFlags = 0;
    blend.SourceConstantAlpha = 50; // 整体透明度
    blend.AlphaFormat = AC_SRC_ALPHA;

    UpdateLayeredWindow(hwnd, hdcScreen, nullptr, &sizeWnd, hdcMem, &ptSrc, 0, &blend, ULW_ALPHA);

    SelectObject(hdcMem, oldBitmap);
    DeleteObject(hBitmap);
    DeleteDC(hdcMem);
    ReleaseDC(nullptr, hdcScreen);
}

int WINAPI WinMain(HINSTANCE hInstance, HINSTANCE, LPSTR, int) {
    // 初始化 GDI+
    ULONG_PTR gdiplusToken;
    GdiplusStartupInput gdiplusStartupInput;
    GdiplusStartup(&gdiplusToken, &gdiplusStartupInput, nullptr);

    // 获取计算机名
    wchar_t computerName[MAX_COMPUTERNAME_LENGTH + 1] = { 0 };
    DWORD size = MAX_COMPUTERNAME_LENGTH + 1;
    if (GetComputerNameW(computerName, &size)) {
        watermarkText = L"机器 - ";
        watermarkText += computerName;
    }
    else {
        watermarkText = L"机器 - Unknown PC";
    }

    WNDCLASS wc = {};
    wc.lpfnWndProc = WndProc;
    wc.hInstance = hInstance;
    wc.lpszClassName = CLASS_NAME;
    wc.hbrBackground = (HBRUSH)GetStockObject(NULL_BRUSH);
    RegisterClass(&wc);

    // 枚举所有显示器，为每个显示器创建水印窗口
    std::vector<HWND> windows;
    EnumDisplayMonitors(nullptr, nullptr,
        [](HMONITOR hMon, HDC, LPRECT lprcMonitor, LPARAM lp) -> BOOL {
            MONITORINFO mi = {};
            mi.cbSize = sizeof(mi);
            GetMonitorInfo(hMon, &mi);

            int x = mi.rcMonitor.left;
            int y = mi.rcMonitor.top;
            int width = mi.rcMonitor.right - mi.rcMonitor.left;
            int height = mi.rcMonitor.bottom - mi.rcMonitor.top;

            HWND hwnd = CreateWindowExW(
                WS_EX_LAYERED | WS_EX_TRANSPARENT | WS_EX_TOPMOST | WS_EX_NOACTIVATE,
                CLASS_NAME, L"", WS_POPUP,
                x, y, width, height,
                nullptr, nullptr, (HINSTANCE)lp, nullptr);

            ShowWindow(hwnd, SW_SHOW);
            DrawWatermark(hwnd, width, height);

            LONG exStyle = GetWindowLong(hwnd, GWL_EXSTYLE);
            SetWindowLong(hwnd, GWL_EXSTYLE, exStyle | WS_EX_LAYERED | WS_EX_TRANSPARENT);

            return TRUE;
        },
        (LPARAM)hInstance);

    MSG msg;
    while (GetMessage(&msg, nullptr, 0, 0)) {
        TranslateMessage(&msg);
        DispatchMessage(&msg);
    }

    GdiplusShutdown(gdiplusToken);
    return 0;
}