5인용C++스터디/윈도우에그림그리기

GDI ¶

GDI(Graphics Device Interface)�� 그��기�� . �� 과 �� 그�� 고 �� . �� Windows�� 그�� GDI�� 각�� Windows �� GDI�� , �� , ��, 그��고 �� 각�� .

DC ¶

DC(Device Context)�� GDI�� 구�� 그�� 기 �� ��. 그�� 그��고�� DC�� . ��그�� Windows�� 그 �� . 그�� GDI �� 그��고�� Windows�� .

�� : �� 그�� .

�� /�� �� 기 �� ��.

DC �� 기 ¶

DC �� 고 �� WM_PAINT �� BeginPaint�� EndPaint �� .

hdc = BeginPaint (hwnd, &ps);
��
EndPaint (hwnd, &ps);

�� 그�� .
�� ps�� PAINTSTRUCT �� 구��. PAINTSTRUCT 구�� 그�� .

WM_PAINT ¶

�� 그�� WinMain�� UpdateWindow�� . �� 금 �� 그��게 ��.

WM_PAINT �� 거�� BeginPaint�� .

hdc = BeginPaint (hwnd, &ps);

그��고 ��과 �� EndPaint�� .

EndPaint (hwnd, &ps);

�� 경�� 그�� . �� PAINTSTRUCT �� 구�� . PAINTSTRUCT 구�� 그�� .

WndProc�� BeginPaint�� 고 �� GetClientRect�� .

GetClientRect(hwnd, &rect);

�� 그�� . �� RECT�� 각�� 구�� .

�� ¶

~cpp 
#include <windows.h>

LRESULT CALLBACK WndProc(HWND,UINT,WPARAM,LPARAM);

int WINAPI WinMain(HINSTANCE hInst, HINSTANCE hPrev, LPSTR lpCmdLine, int nCmdShow)
{
	HWND hWnd;
	WNDCLASS wc;
	MSG mSg;
	char szTitleName[]="Drawing Line";
	char szClassName[]="it is a class";

	wc.cbClsExtra=NULL;
	wc.cbWndExtra=NULL;
	wc.hbrBackground=(HBRUSH)GetStockObject(WHITE_BRUSH);
	wc.hCursor=LoadCursor(NULL,IDC_ARROW);
	wc.hIcon=LoadIcon(NULL,IDI_APPLICATION);
	wc.hInstance=hInst;
	wc.lpfnWndProc=WndProc;
	wc.lpszClassName=szClassName;
	wc.lpszMenuName=NULL;
	wc.style=NULL;

	RegisterClass(&wc);

	hWnd=CreateWindow(szClassName,szTitleName, WS_OVERLAPPEDWINDOW,100,90,320,240,NULL,NULL,hInst,NULL);

	ShowWindow(hWnd,nCmdShow);
	UpdateWindow(hWnd);

	while(GetMessage(&mSg,NULL,0,0))
	{
		TranslateMessage(&mSg);
		DispatchMessage(&mSg);
	}
	return mSg.wParam;
}

LRESULT CALLBACK WndProc(
						 HWND hWnd,
						 UINT uMsg,
						 WPARAM wParam,
						 LPARAM lParam)
{
	HDC hDC;
	HPEN hPen;
	PAINTSTRUCT ps;
	static int nSX,nSY,nEX,nEY;
	static POINT pt;
	static BOOL bTF;

	switch(uMsg)
	{
	case WM_LBUTTONDOWN:
		{
			bTF = TRUE;
			nSX=LOWORD(lParam);
			nSY=HIWORD(lParam);
		}
		return FALSE;

	case WM_LBUTTONUP:
		{
			bTF=FALSE;
			nEX=LOWORD(lParam);
			nEY=HIWORD(lParam);
			InvalidateRect(hWnd,NULL,FALSE);
		}
		return FALSE;

	case WM_PAINT:
		{
			if(bTF==FALSE)
			{
				hPen=CreatePen(PS_SOLID,0,RGB(0,0,0));
				hDC=BeginPaint(hWnd,&ps);
				SelectObject(hDC,hPen);
                                    SelectObject(hDC, GetStockObject(NULL_BRUSH));
 				MoveToEx(hDC,nSX,nSY,&pt);
				LineTo(hDC,nEX,nEY);
				DeleteObject(hPen);
				EndPaint(hWnd,&ps);
			}
		}
			return FALSE;
	case WM_DESTROY:
		PostQuitMessage(0);
		return FALSE;
		}
		return DefWindowProc(hWnd,uMsg,wParam,lParam);
	}

~cpp 
                               hPen=CreatePen(PS_SOLID,0,RGB(0,0,0)); 
                               hDC=BeginPaint(hWnd,&ps); 
                               Ellipse(hDC,nSX,nSY,nEX,nEY);
                               EndPaint(hWnd,&ps);

CreatePen() : �� .
SelectObject() : CreatePen()�� .
LineTO() : �� 그�� .
DeleteObject() : CreatePen()�� .

5��C++��