[핵심 API로 배우는 윈도우프로그래밍(강경우, 한빛아카데미)] 3장 12번 풀이

#include <Windows.h>
#include<tchar.h>
#include<string.h>
#include<math.h>
LRESULT CALLBACK WndProc(HWND hwnd, UINT iMsg, WPARAM wParam, LPARAM lParam);
 
int WINAPI WinMain(HINSTANCE hInstance, HINSTANCE hPrevInstance, LPSTR lpszCmdLine, int nCmdShow)
{
    HWND hwnd;
    MSG msg;
 
    WNDCLASS WndClass;
    WndClass.style = CS_HREDRAW | CS_VREDRAW;
    WndClass.lpfnWndProc = WndProc;
    WndClass.cbClsExtra = 0;
    WndClass.cbWndExtra = 0;
    WndClass.hInstance = hInstance;
    WndClass.hIcon = LoadIcon(NULL, IDI_APPLICATION);
    WndClass.hCursor = LoadCursor(NULL, IDC_ARROW);
    WndClass.hbrBackground = (HBRUSH)GetStockObject(WHITE_BRUSH);
    WndClass.lpszMenuName = NULL;
    WndClass.lpszClassName = _T("Window Class Name");
 
    RegisterClass(&WndClass); //윈도우 클래스를 커널에 등록
 
    hwnd = CreateWindow( //윈도우 핸들값 반환
        _T("Window Class Name"), //윈도우 클래스 이름
        _T("홍길동의 첫 번째 윈도우"), //윈도우 타이틀이름
        WS_OVERLAPPEDWINDOW, //윈도우 스타일
        100, //윈도우 위치 x좌표
        100,//윈도우 위치 y좌표
        1000, //윈도우 가로크기
        600, //윈도우 세로크기
        NULL, //부모 윈도우핸들
        NULL, //메뉴핸들
        hInstance, //응용프로그램 인스턴스
        NULL); //생성 윈도우 정보
 
    ShowWindow(hwnd, nCmdShow);
    UpdateWindow(hwnd);
 
    while (GetMessage(&msg, NULL, 0, 0))
    {
        TranslateMessage(&msg);
        DispatchMessage(&msg);
    }
    return (int)msg.wParam;
}
 
LRESULT CALLBACK WndProc(HWND hwnd, UINT iMsg, WPARAM wParam, LPARAM lParam)
{
    HDC hdc;
    PAINTSTRUCT ps;
    HPEN redPen, blackPen, bluePen;
    static int  mX, mY;
    static int circleX[4][8], circleY[4][8];
    static int circleColor[4][8];
    static int circleCount = 0;
    switch (iMsg)
    {
    case WM_CREATE:
        for (int i = 0; i < 4; i++)
            for (int j = 0; j < 8; j++)
            {
                circleX[i][j] = -100;
                circleY[i][j] = -100;
                circleColor[i][j] = 0;
            }
 
        InvalidateRgn(hwnd, NULL, TRUE);
        break;
    case WM_LBUTTONDOWN:
        hdc = GetDC(hwnd);
        for (int i = 0; i < 5; i++)            //--------------프레임
        {
            MoveToEx(hdc, 0, i * 100, NULL);
            LineTo(hdc, 800, i * 100);
        }
        for (int i = 0; i < 9; i++)
        {
            MoveToEx(hdc, i * 100, 0, NULL);
            LineTo(hdc, i * 100, 400);
        }                                    //--------------프레임
        mX = LOWORD(lParam);
        mY = HIWORD(lParam);
        circleX[mY / 100][mX / 100] = (mX / 100) * 100;
        circleY[mY / 100][mX / 100] = (mY / 100) * 100;
        if (circleColor[mY / 100][mX / 100] == 0)
            circleColor[mY / 100][mX / 100] = 1; //빨강
        else if (circleColor[mY / 100][mX / 100] == 1)
            circleColor[mY / 100][mX / 100] = 2; //파랑
        else if (circleColor[mY / 100][mX / 100] == 2)
            circleColor[mY / 100][mX / 100] = 1; //빨강
        blackPen = CreatePen(PS_SOLID, 1, RGB(0, 0, 0));
        redPen = CreatePen(PS_SOLID, 1, RGB(255, 0, 0));
        bluePen = CreatePen(PS_SOLID, 1, RGB(0, 0, 255));
        for (int i = 0; i < 4; i++)
            for (int j = 0; j < 8; j++)
            {
 
                if (circleColor[i][j] == 1)
                    SelectObject(hdc, redPen);
                else if (circleColor[i][j] == 2)
                    SelectObject(hdc, bluePen);
                Ellipse(hdc, circleX[i][j], circleY[i][j], circleX[i][j] + 100, circleY[i][j] + 100);
            }
        ReleaseDC(hwnd, hdc);
        //InvalidateRgn(hwnd, NULL, TRUE);
        break;
    case WM_LBUTTONUP:
        break;
    case WM_MOUSEMOVE:
        break;
    case WM_PAINT:
        hdc = BeginPaint(hwnd, &ps);
 
        for (int i = 0; i < 5; i++)            //--------------프레임
        {
            MoveToEx(hdc, 0, i * 100, NULL);
            LineTo(hdc, 800, i * 100);
        }
        for (int i = 0; i < 9; i++)
        {
            MoveToEx(hdc, i * 100, 0, NULL);
            LineTo(hdc, i * 100, 400);
        }                                    //--------------프레임
 
        EndPaint(hwnd, &ps);
        break;
    case WM_DESTROY:
        PostQuitMessage(0);
        break;
 
    }
    return DefWindowProc(hwnd, iMsg, wParam, lParam);
}