C/Visual C - REPRESENTACION GRAFICA PORCENTAJES CIRCULAR EN C

#include <windows.h>

#include <cmath>

#define PI 3.14159265

LRESULT CALLBACK WindowProc(HWND hwnd, UINT uMsg, WPARAM wParam, LPARAM lParam) {

    switch (uMsg) {

        case WM_PAINT: {

            PAINTSTRUCT ps;

            HDC hdc = BeginPaint(hwnd, &ps);

            // Datos de porcentajes

            double percentages[] = { 25.0, 35.0, 20.0, 20.0 }; // Porcentajes

            int numSegments = sizeof(percentages) / sizeof(percentages[0]);

            int radius = 100; // Radio del círculo

            int centerX = 200; // Centro del círculo

            int centerY = 200;

            // Variables para el ángulo

            double startAngle = 0.0;

            // Dibujar cada segmento

            for (int i = 0; i < numSegments; i++) {

                double angle = percentages[i] * 360.0 / 100.0; // Convertir porcentaje a ángulo

                double endAngle = startAngle + angle;

                // Calcular las coordenadas del arco

                POINT startPoint = {

                    static_cast<LONG>(centerX + radius * cos(startAngle * PI / 180)),

                    static_cast<LONG>(centerY - radius * sin(startAngle * PI / 180))

                };

                POINT endPoint = {

                    static_cast<LONG>(centerX + radius * cos(endAngle * PI / 180)),

                    static_cast<LONG>(centerY - radius * sin(endAngle * PI / 180))

                };

                // Dibujar el arco

                Arc(hdc, centerX - radius, centerY - radius, centerX + radius, centerY + radius,

                    endPoint.x, endPoint.y, startPoint.x,startPoint.y);

                // Actualizar el ángulo de inicio

                startAngle += angle;

            }

            EndPaint(hwnd, &ps);

        } break;

        case WM_DESTROY:

            PostQuitMessage(0);

            return 0;

    }

    return DefWindowProc(hwnd, uMsg, wParam, lParam);

}

int WINAPI WinMain(HINSTANCE hInstance, HINSTANCE, LPSTR, int nShowCmd) {

    const char CLASS_NAME[] = "MiClaseVentana";

    WNDCLASS wc = {};

    wc.lpfnWndProc = WindowProc;

    wc.hInstance = hInstance;

    wc.lpszClassName = CLASS_NAME;

    RegisterClass(&wc);

    HWND hwnd = CreateWindowEx(0, CLASS_NAME, "Círculo de porcentajes", WS_OVERLAPPEDWINDOW,

                               CW_USEDEFAULT, CW_USEDEFAULT, 400, 400,

                               NULL, NULL, hInstance, NULL);

    ShowWindow(hwnd, nShowCmd);

    MSG msg;

    while (GetMessage(&msg, NULL, 0, 0)) {

        TranslateMessage(&msg);

        DispatchMessage(&msg);

    }

    return 0;

}