sample.cpp

#define _CRT_SECURE_NO_WARNINGS
#include <Windows.h>
#include <cstdio>
#include <cmath>

float x = 0, y = 0;
int targetX = 0, targetY = 0;
float angle;

HBITMAP myBitmap;

LRESULT CALLBACK WndProc ( HWND hWnd, UINT uMsg, WPARAM wParam, LPARAM lParam )
{
	switch ( uMsg )
	{
	case WM_CREATE:
		myBitmap = ( HBITMAP ) LoadImage ( GetModuleHandle ( nullptr ), L"sample.bmp", IMAGE_BITMAP, 320, 320, LR_LOADFROMFILE );
		break;

	case WM_PAINT:
		{
			PAINTSTRUCT ps;
			// 창의 기본 DC를 가져온다
			HDC hDC = BeginPaint ( hWnd, &ps );
			// 기본 DC의 호환 DC (Compatible DC)를 생성한다
			// 호환 DC는 기본 DC와 시스템적으로 동일한 구성 (색의 가지수 등)을 가지게 된다
			HDC hCompDC = CreateCompatibleDC ( hDC );
			// 기본 DC의 호환 비트맵 (Compatible Bitmap)을 생성한다.
			// 동일한 색상 깊이를 가지게 되므로 색이 깨지지 않는다.
			HBITMAP hCompBitmap = CreateCompatibleBitmap ( hDC, 800, 600 );
			// 호환 DC에 호환 비트맵을 적용
			HBITMAP oldBitmap = ( HBITMAP ) SelectObject ( hCompDC, hCompBitmap );

			HDC bitmapDC = CreateCompatibleDC ( hCompDC );
			HBITMAP oldBitmapDCBitmap = ( HBITMAP ) SelectObject ( bitmapDC, myBitmap );
			BitBlt ( hCompDC, x, y, 320, 320, bitmapDC, 0, 0, SRCCOPY );
			SelectObject ( bitmapDC, oldBitmapDCBitmap );
			DeleteDC ( bitmapDC );

			// 호환 DC를 기본 DC에 BitBlt로 고속으로 복사한다
			BitBlt ( hDC, 0, 0, 800, 600, hCompDC, 0, 0, SRCCOPY );

			// 사용이 끝난 호환 DC 및 비트맵을 제거한다.
			SelectObject ( hCompDC, oldBitmap );
			DeleteObject ( hCompBitmap );
			DeleteDC ( hCompDC );
			// 창의 기본 DC를 해제한다
			EndPaint ( hWnd, &ps );
		}
		break;

	case WM_LBUTTONDOWN:
		targetX = LOWORD ( lParam );
		targetY = HIWORD ( lParam );

		printf ( "targetX = %d, targetY = %d\n", targetX, targetY );

		angle = atan2f (targetY - y, targetX - x);
		break;

	case WM_CLOSE:
		DeleteObject ( myBitmap );
		PostQuitMessage ( 0 );
		break;

	default:
		return DefWindowProc ( hWnd, uMsg, wParam, lParam );
	}

	return 0;
}

int WINAPI WinMain ( HINSTANCE hInstance, HINSTANCE hPrevInstance, LPSTR lpszCmdLine, int nCmdShow )
{
	WNDCLASS wndClass = { CS_VREDRAW | CS_HREDRAW, WndProc, 0, 0, hInstance, 0, 0, ( HBRUSH ) GetStockObject ( WHITE_BRUSH ), nullptr, L"asdf" };
	RegisterClass ( &wndClass );

	RECT rect = { 0, 0, 800, 600 };
	AdjustWindowRect ( &rect, WS_OVERLAPPEDWINDOW, FALSE );
	int width = rect.right - rect.left, height = rect.bottom - rect.top;
	int _x = GetSystemMetrics ( SM_CXSCREEN ) / 2 - width / 2, _y = GetSystemMetrics ( SM_CYSCREEN ) / 2 - height / 2;
	HWND hWnd = CreateWindow ( L"asdf", L"Test", WS_OVERLAPPEDWINDOW, _x, _y, width, height, nullptr, nullptr, hInstance, nullptr );

	ShowWindow ( hWnd, SW_SHOW );
	UpdateWindow ( hWnd );

	AllocConsole ();
	freopen ( "CONOUT$", "w", stdout );

	MSG msg;
	while ( true )
	{
		if ( PeekMessage ( &msg, nullptr, 0, 0, PM_NOREMOVE ) )
		{
			if ( !GetMessage ( &msg, nullptr, 0, 0 ) )
				break;
			TranslateMessage ( &msg );
			DispatchMessage ( &msg );
		}
		else
		{
			if ( targetX != x )
			{
				float tempX = x;
				x += cos ( angle );
				if ( ( tempX < targetX && x > targetX ) || ( tempX > targetX && x < targetX ) )
					x = targetX;
			}
			if ( targetY != y )
			{
				float tempY = y;
				y += sin ( angle );
				if ( ( tempY < targetY && y > targetY ) || ( tempY > targetY && y < targetY ) )
					y = targetY;
			}
			printf ( "x: %f, y: %f\n", x, y );

			InvalidateRect ( hWnd, nullptr, FALSE );
			Sleep ( 1 );
		}
	}
}