lightweight Win32 temperature monitor using LibreHardwareMonitor and lhwm-wrapper

main.cpp

/*
Requires:
1. LibreHardwareMonitorLib.dll from https://github.com/LibreHardwareMonitor/LibreHardwareMonitor/
2. lhwm-wrapper.dll, lhwm-cpp-wrapper.lib & lhwm-cpp-wrapper.h from https://gitlab.com/OpenRGBDevelopers/OpenRGBHardwareSyncPlugin/-/tree/master/dependencies/lhwm-cpp-wrapper/

Link with lhwm-cpp-wrapper.lib, dwmapi.lib & mscoree.lib from .NET Framework 4.x

No config, manually adjust location, text size & style, monitored values and update delay in UpdateOverlay() and the code for the update thread in WinMain()
*/
#define WIN32_LEAN_AND_MEAN 
#include <windows.h>
#include <shellapi.h>
#include <thread>
#include <sstream>
#include <iomanip>
#include <dwmapi.h>
#include "lhwm-cpp-wrapper.h"

NOTIFYICONDATA nid = {};

LRESULT CALLBACK WindowProc(HWND hwnd, UINT uMsg, WPARAM wParam, LPARAM lParam) {
    switch(uMsg) {
        case WM_APP + 1:
            if (LOWORD(lParam) == WM_RBUTTONUP) {
                HMENU hMenu = CreatePopupMenu();
                AppendMenu(hMenu, MF_STRING, 1, L"Exit");
                POINT pt;
                GetCursorPos(&pt);
                SetForegroundWindow(hwnd);
                int cmd = TrackPopupMenu(hMenu, TPM_RETURNCMD | TPM_NONOTIFY, pt.x, pt.y, 0, hwnd, nullptr);
                if (cmd == 1) {
                    Shell_NotifyIcon(NIM_DELETE, &nid);
                    std::exit(0);
                }
                DestroyMenu(hMenu);
            }
            break;
        case WM_DESTROY:
            std::exit(0);
            break;
    }
    return DefWindowProc(hwnd, uMsg, wParam, lParam);
}

void UpdateOverlay(HWND hwnd, const std::wstring& text) {
    HDC hdc = GetDC(hwnd);
    RECT rect;
    GetClientRect(hwnd, &rect);
    FillRect(hdc, &rect, (HBRUSH)GetStockObject(BLACK_BRUSH));

    HFONT hFont = CreateFont(17, 0, 0, 0, FW_NORMAL, FALSE, FALSE, FALSE, DEFAULT_CHARSET, OUT_OUTLINE_PRECIS, CLIP_DEFAULT_PRECIS, CLEARTYPE_QUALITY, VARIABLE_PITCH, L"Arial");
    SelectObject(hdc, hFont);

    SetTextColor(hdc, RGB(0, 0, 0));
    SetBkMode(hdc, TRANSPARENT);
    RECT shadowRect = rect;
    shadowRect.left += 1;
    shadowRect.top += 1;
    DrawText(hdc, text.c_str(), -1, &shadowRect, DT_LEFT | DT_TOP);

    SetTextColor(hdc, RGB(255, 255, 255));
    DrawText(hdc, text.c_str(), -1, &rect, DT_LEFT | DT_TOP);

    DeleteObject(hFont);
    ReleaseDC(hwnd, hdc);
}
std::wstring FormatFloat(float value, int precision = 2) {
    std::wostringstream oss;
    oss << std::fixed << std::setprecision(precision) << value;
    return oss.str();
}

int WINAPI WinMain(HINSTANCE hInstance, HINSTANCE, LPSTR, int) {
    const wchar_t CLASS_NAME[] = L"OverlayWindowClass";
    WNDCLASS wc = { };
    wc.lpfnWndProc = WindowProc;
    wc.hInstance = hInstance;
    wc.lpszClassName = CLASS_NAME;
    wc.hbrBackground = (HBRUSH)GetStockObject(HOLLOW_BRUSH);

    RegisterClass(&wc);
    HWND hwnd = CreateWindowEx(
        WS_EX_LAYERED | WS_EX_TRANSPARENT | WS_EX_TOOLWINDOW | WS_EX_NOACTIVATE,
        CLASS_NAME,
        L"temps",
        WS_POPUP,
        5, 75, 300, 150,
        nullptr, nullptr, hInstance, nullptr
    );

    SetLayeredWindowAttributes(hwnd, RGB(0, 0, 0), 0, LWA_COLORKEY);
    ShowWindow(hwnd, SW_SHOW);
    SetWindowPos(hwnd, HWND_BOTTOM, 0, 0, 0, 0, SWP_NOMOVE | SWP_NOSIZE);
    BOOL excludeFromPeek = TRUE;
    DwmSetWindowAttribute(hwnd, DWMWA_EXCLUDED_FROM_PEEK, &excludeFromPeek, sizeof(excludeFromPeek));

    nid.cbSize = sizeof(NOTIFYICONDATA);
    nid.hWnd = hwnd;
    nid.uID = 1;
    nid.uFlags = NIF_ICON | NIF_MESSAGE | NIF_TIP;
    nid.uCallbackMessage = WM_APP + 1;
    nid.hIcon = LoadIcon(nullptr, IDI_APPLICATION);
    wcscpy_s(nid.szTip, L"temps");
    Shell_NotifyIcon(NIM_ADD, &nid);

    std::thread overlayThread([hwnd]() {
        do {
            UpdateOverlay(hwnd, 
                L"CPU: " + FormatFloat(LHWM::GetSensorValue("/amdcpu/0/temperature/3")) + L"°C " +
                L"(" + FormatFloat(LHWM::GetSensorValue("/amdcpu/0/temperature/2")) + L"°C offset)\n" +
                L"CPU core voltage: " + FormatFloat(LHWM::GetSensorValue("/amdcpu/0/voltage/0"), 4) + L"V)\n" +
                L"max core load: " + FormatFloat(LHWM::GetSensorValue("/amdcpu/0/load/1"), 0) + L"% " +
                L"(" + FormatFloat(LHWM::GetSensorValue("/amdcpu/0/load/0"), 0) + L"% load total)\n" +
                L"SSD: " + FormatFloat(LHWM::GetSensorValue("/ssd/2/temperature/0"), 0) + L"°C " +
                L"(" + FormatFloat(LHWM::GetSensorValue("/ssd/2/level/0"), 0) + L"% remaining life)\n" +
                L"HDDs: #1 " + FormatFloat(LHWM::GetSensorValue("/hdd/0/temperature/0"), 0) + L"°C - " +
                L"#2 " + FormatFloat(LHWM::GetSensorValue("/hdd/1/temperature/0"), 0) + L"°C\n" +
                L"GPU: " + FormatFloat(LHWM::GetSensorValue("/gpu-nvidia/0/temperature/0")) + L"°C " +
                L"(" + FormatFloat(LHWM::GetSensorValue("/gpu-nvidia/0/temperature/2")) + L"°C hot spot)"
            );
            std::this_thread::sleep_for(std::chrono::seconds(7));
        } while (true);
        PostQuitMessage(0);
    });

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

    overlayThread.join();
    Shell_NotifyIcon(NIM_DELETE, &nid);
    return 0;
}