[핵심 API로 배우는 윈도우프로그래밍(강경우, 한빛아카데미)] 10장 2번 풀이

#include <Windows.h>
#include<tchar.h>
#include<string.h>
#include<winres.h>
#include<process.h>
#include<time.h>
#include<stdio.h>
#include<stdlib.h>
//#pragma comment(linker,"/entry:WinMainCRTStartup /subsystem:console")
 
LRESULT CALLBACK WndProc(HWND hwnd, UINT iMsg, WPARAM wParam, LPARAM lParam);
void ThreadProc();
HINSTANCE hInst;
HWND hwnd;
 
int WINAPI WinMain(HINSTANCE hInstance, HINSTANCE hPrevInstance, LPSTR lpszCmdLine, int nCmdShow)
{
    MSG msg;
    WNDCLASS WndClass;
 
    hInst = hInstance;
    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);
 
    hwnd = CreateWindow(
        _T("Window Class Name"),
        _T("박정호"),
        WS_OVERLAPPEDWINDOW,
        50,
        50,
        1000,
        700,
        NULL,
        NULL,
        hInstance,
        NULL);
 
    ShowWindow(hwnd, nCmdShow);
    UpdateWindow(hwnd);
 
    while (GetMessage(&msg, NULL, 0, 0))
    {
        TranslateMessage(&msg);
        DispatchMessage(&msg);
    }
    return (int)msg.wParam;
}
int xPos = 30, yPos = 30;
static RECT rt;
HANDLE hEvent;
BOOL directionX = TRUE;
BOOL directionY = TRUE;
LRESULT CALLBACK WndProc(HWND hwnd, UINT iMsg, WPARAM wParam, LPARAM lParam)
{
    HDC hdc;
    PAINTSTRUCT ps;
    static HANDLE hThread;
    static int count = 0;
    static BOOL GO = FALSE;
    static BOOL init = TRUE;
    switch (iMsg)
    {
    case WM_CREATE:
        GetClientRect(hwnd, &rt);
        hEvent = CreateEvent(NULL, TRUE, TRUE, NULL);
        break;
 
    case WM_LBUTTONDOWN:
        if (init)
        {
            hThread = (HANDLE)_beginthreadex(NULL, 0, (unsigned int(__stdcall *)(void *))ThreadProc, NULL, 0, NULL);
            init = FALSE;
        }
        if (GO)                //멈춤
        {
            ResetEvent(hEvent);
            GO = FALSE;
        }
        else                //시작
        {
            SetEvent(hEvent);
            GO = TRUE;
        }
 
        break;
    case WM_PAINT:
        hdc = BeginPaint(hwnd, &ps);
        Ellipse(hdc, xPos - 20, yPos - 20, xPos + 20, yPos + 20);
        EndPaint(hwnd, &ps);
        break;
    case WM_DESTROY:
        CloseHandle(hThread);
        PostQuitMessage(0);
        break;
 
    }
    return DefWindowProc(hwnd, iMsg, wParam, lParam);
}
void ThreadProc()
{
    HDC hdc;
 
    hdc = GetDC(hwnd);
    while (1)
    {
        WaitForSingleObject(hEvent, INFINITE);
        if (xPos < 20 || xPos>rt.right - 20)
            directionX = directionX ? FALSE : TRUE;
        if (yPos < 20 || yPos>rt.bottom - 20)
            directionY = directionY ? FALSE : TRUE;
 
        if (directionX)
            xPos++;
        else
            xPos--;
 
        if (directionY)
            yPos++;
        else
            yPos--;
 
        InvalidateRgn(hwnd, NULL, TRUE);
        Sleep(5);
    }
    ReleaseDC(hwnd, hdc);
    return;
}