2.1 文字列の表示

(1) 画像としての文字列

#include "myWin.h"
void procLeftButtonDown(HWND hw, WPARAM wp,LPARAM lp){
	HDC hdc=GetDC(hw);LPTSTR lptstr=TEXT("ようこそ Windowsへ");
	TextOut(hdc, 10,10, lptstr, lstrlen(lptstr));
	ReleaseDC(hw,hdc);
}
LRESULT CALLBACK WndProc(HWND hw, UINT msg, WPARAM wp,LPARAM lp){
	switch(msg){
 	case WM_DESTROY : PostQuitMessage(0)   ; return 0;
	case WM_LBUTTONDOWN : procLeftButtonDown(hw,wp,lp); return 0;
	}
	return DefWindowProc(hw,msg,wp,lp);
}

(2) クライアントエリアの更新

#include "myWin.h"
void procPaint(HWND hw, WPARAM wp,LPARAM lp){
	HDC hdc=GetDC(hw);LPTSTR lptstr=TEXT("ようこそ Windowsへ");
	TextOut(hdc, 10,10, lptstr, lstrlen(lptstr));
	ReleaseDC(hw,hdc);
}
LRESULT CALLBACK WndProc(HWND hw, UINT msg, WPARAM wp,LPARAM lp){
	switch(msg){
 	case WM_DESTROY : PostQuitMessage(0) ; return 0;
	case WM_PAINT   : procPaint(hw,wp,lp); return 0;
	}
	return DefWindowProc(hw,msg,wp,lp);
}


(3) 2行に分けて描画する

【procPaintのみ】

void procPaint(HWND hw, WPARAM wp,LPARAM lp){
	PAINTSTRUCT ps;TEXTMETRIC tm;
	HDC hdc=BeginPaint(hw, &ps); GetTextMetrics(hdc,&tm);
	LPTSTR lptstr=TEXT("ようこそ Windowsへ");
	int len=lstrlen(lptstr);
	TextOut(hdc, 10,10            , lptstr, len);
	TextOut(hdc, 10,10+tm.tmHeight, lptstr, len);
	ReleaseDC(hw,hdc);
}

(4) 文字色・背景色

【procPaintのみ】

void procPaint(HWND hw, WPARAM wp,LPARAM lp){
	PAINTSTRUCT ps;TEXTMETRIC tm;
	HDC hdc=BeginPaint(hw, &ps); GetTextMetrics(hdc,&tm);
	LPTSTR lptstr=TEXT("ようこそ Windowsへ");
	int len=lstrlen(lptstr);
	SetTextColor(hdc,0xFF0000);
	SetBkColor(hdc,RGB(0xCF,0xCF,0xCF));
	TextOut(hdc, 10,10            , lptstr, len);
	SetTextColor(hdc,RGB(255,0,0));
	SetBkMode(hdc,TRANSPARENT);
	TextOut(hdc, 10,10+tm.tmHeight, lptstr, len);
	EndPaint(hw,&ps);
}

(5) 描画領域のサイズと動的な改行

【procPaintのみ】

void procPaint(HWND hw, WPARAM wp,LPARAM lp){
	PAINTSTRUCT ps;RECT rect;
	HDC hdc=BeginPaint(hw, &ps); GetClientRect(hw,&rect);
	LPTSTR lptstr=TEXT("the world, the flesh, and the devil");
	DrawText(hdc, lptstr,-1,&rect,DT_CENTER | DT_WORDBREAK);
	EndPaint(hw,&ps);
}

(6) フォントの指定

【procPaintのみ】

void procPaint(HWND hw, WPARAM wp,LPARAM lp){
	PAINTSTRUCT ps;LPTSTR lptstr = TEXT("She twisted flowers into a wreath.");
	HDC   hdc=BeginPaint(hw, &ps);
	HFONT hF =CreateFont(
		32, 0, 0, 0, FW_BOLD, TRUE, TRUE, FALSE, SHIFTJIS_CHARSET,
		OUT_DEFAULT_PRECIS, CLIP_DEFAULT_PRECIS, DEFAULT_QUALITY,
		VARIABLE_PITCH | FF_ROMAN,NULL);
	SelectObject(hdc, hF);
	TextOut(hdc,10,10,lptstr,lstrlen(lptstr));
	EndPaint(hw,&ps);
}

【回転】

	HFONT hF=CreateFont(
		32, 0,-350,-350, FW_BOLD, TRUE, TRUE, FALSE, SHIFTJIS_CHARSET,
		OUT_DEFAULT_PRECIS, CLIP_DEFAULT_PRECIS, DEFAULT_QUALITY,
		VARIABLE_PITCH | FF_ROMAN,NULL);
	SelectObject(hdc, hF);
	TextOut(hdc,100,10,lptstr,lstrlen(lptstr));
	
(7) LOGFONT構造体を使用する方法

#include "myWin.h"
static LOGFONT lfF; 
void procCreate(HWND hw, WPARAM wp,LPARAM lp){
	lfF.lfHeight		= 32;
	lfF.lfWidth			= lfF.lfEscapement = lfF.lfOrientation = 0;
	lfF.lfWeight		= FW_BOLD;
	lfF.lfItalic		= lfF.lfUnderline = TRUE;
	lfF.lfStrikeOut		= FALSE;
	lfF.lfCharSet		= SHIFTJIS_CHARSET;
	lfF.lfOutPrecision	= OUT_DEFAULT_PRECIS;
	lfF.lfClipPrecision	= CLIP_DEFAULT_PRECIS;
	lfF.lfQuality		= DEFAULT_QUALITY;
	lfF.lfPitchAndFamily= 0; lfF.lfFaceName[0]	= '\0';
}
void procPaint(HWND hw, WPARAM wp,LPARAM lp){
	PAINTSTRUCT ps;
	LPTSTR lptstr = TEXT("She twisted flowers into a wreath.");
	HDC hdc=BeginPaint(hw, &ps); HFONT hF= CreateFontIndirect(&lfF);
	SelectObject(hdc, hF); TextOut(hdc,100,10,lptstr,lstrlen(lptstr));
	SelectObject(hdc,GetStockObject(SYSTEM_FONT));
	DeleteObject(hF); EndPaint(hw,&ps);
}
LRESULT CALLBACK WndProc(HWND hw, UINT msg, WPARAM wp,LPARAM lp){
	switch(msg){
 	case WM_DESTROY : PostQuitMessage(0)  ; return 0;
	case WM_CREATE  : procCreate(hw,wp,lp); return 0;
	case WM_PAINT   : procPaint (hw,wp,lp); return 0;
	}
	return DefWindowProc(hw,msg,wp,lp);
}

2.2  点の描画

void procPaint(HWND hw, WPARAM wp,LPARAM lp){
	PAINTSTRUCT ps;	HDC hdc=BeginPaint(hw, &ps);
	for(int i=0;i<100;i++) SetPixel(hdc,10+i,10,0xFF0000);
	EndPaint(hw,&ps);
}
LRESULT CALLBACK WndProc(HWND hw, UINT msg, WPARAM wp,LPARAM lp){
	switch(msg){
 	case WM_DESTROY : PostQuitMessage(0)  ; return 0;
	case WM_PAINT   : procPaint (hw,wp,lp); return 0;
	}
	return DefWindowProc(hw,msg,wp,lp);
}


2.3  線の描画

(1)カレントポジションと線分

【procPaintのみ】

void procPaint(HWND hw, WPARAM wp,LPARAM lp){
	PAINTSTRUCT ps;	HDC hdc=BeginPaint(hw, &ps);
	MoveToEx(hdc,10,10,NULL); 
	LineTo(hdc,60,110);
	 LineTo(hdc,110,10);
	EndPaint(hw,&ps);
}

(2)連続線分の描画

#include "myWin.h"
#define NUMPOLY 5
static POINT lpP[NUMPOLY];
void procCreate(HWND hw, WPARAM wp,LPARAM lp){
	lpP[0].x=150; lpP[0].y= 50;
	lpP[1].x=125; lpP[1].y=100;
	lpP[2].x= 75; lpP[2].y=100;
	lpP[3].x= 50; lpP[3].y= 50;
	lpP[4].x=100; lpP[4].y= 10;
}
void procPaint(HWND hw, WPARAM wp,LPARAM lp){
	PAINTSTRUCT ps;
	HDC hdc=BeginPaint(hw, &ps);
	MoveToEx(hdc,100,10,NULL);
	PolylineTo(hdc,lpP,NUMPOLY);
	EndPaint(hw,&ps);
}
LRESULT CALLBACK WndProc(HWND hw, UINT msg, WPARAM wp,LPARAM lp){
	switch(msg){
 	case WM_DESTROY : PostQuitMessage(0)  ; return 0;
	case WM_CREATE  : procCreate(hw,wp,lp); return 0;
	case WM_PAINT   : procPaint (hw,wp,lp); return 0;
	}
	return DefWindowProc(hw,msg,wp,lp);
}	

(3)連続線分を分割して描画

#include "myWin.h"
#define NUMPOLY 5
static POINT lpP[NUMPOLY];static CONST DWORD dw[]={3, 2};
void procCreate(HWND hw, WPARAM wp,LPARAM lp){
	lpP[0].x=150; lpP[0].y= 50;
	lpP[1].x=125; lpP[1].y=100;
	lpP[2].x= 75; lpP[2].y=100;
	lpP[3].x= 50; lpP[3].y= 50;
	lpP[4].x=100; lpP[4].y= 10;
}
void procPaint(HWND hw, WPARAM wp,LPARAM lp){
	PAINTSTRUCT ps;
	HDC hdc=BeginPaint(hw, &ps);
	PolyPolyline(hdc,lpP,dw,2);
	EndPaint(hw,&ps);
}
（WndProc以降は，前項(2)と同じ）

2.4 閉じた図形

(1) 長方形と楕円

#include "myWin.h"
void procPaint(HWND hw, WPARAM wp,LPARAM lp){
	PAINTSTRUCT ps;
	HDC hdc=BeginPaint(hw, &ps);
		MoveToEx(hdc, 0, 0,NULL);
		LineTo(hdc,270,70);
		Rectangle(hdc,10,10,80,60);
		Ellipse  (hdc,100,10,170,60);
		RoundRect(hdc,190,10,260,60,20,20);
	EndPaint(hw,&ps);
}
LRESULT CALLBACK WndProc(HWND hw, UINT msg, WPARAM wp,LPARAM lp){
	switch(msg){
 	case WM_DESTROY : PostQuitMessage(0) ; return 0;
	case WM_PAINT   : procPaint(hw,wp,lp); return 0;
	}
	return DefWindowProc(hw,msg,wp,lp);
}

(2) 円弧・扇形・弓形

【procPaintのみ】

void procPaint(HWND hw, WPARAM wp,LPARAM lp){
	PAINTSTRUCT ps;
	HDC hdc=BeginPaint(hw, &ps);
		Arc  (hdc,  10, 10, 100, 100, 100, 10,  10,55);
		Pie  (hdc, 110, 10, 200, 100, 200, 10, 110,55);
		Chord(hdc, 210, 10, 300, 100, 300, 10, 210,55);
	EndPaint(hw,&ps);
}

2.5 色々な曲線

(1) ベジェ曲線

#include "myWin.h"
static POINT pt[3];
void procCreate(HWND hw, WPARAM wp,LPARAM lp){
		pt[0].x=100; pt[0].y=100;
		pt[1].x=200; pt[1].y=50;
		pt[2].x=300; pt[2].y=100;
}
void procPaint(HWND hw, WPARAM wp,LPARAM lp){
	PAINTSTRUCT ps;RECT rect;
	HDC hdc=BeginPaint(hw, &ps); GetClientRect(hw,&rect);
		MoveToEx(hdc, 10,10,NULL);
		PolyBezierTo(hdc,pt,3);
		MoveToEx(hdc,10,10,NULL);
		PolylineTo(hdc,pt,3);
	EndPaint(hw,&ps);
}
LRESULT CALLBACK WndProc(HWND hw, UINT msg, WPARAM wp,LPARAM lp){
	switch(msg){
 	case WM_DESTROY : PostQuitMessage(0)  ; return 0;
	case WM_CREATE  : procCreate(hw,wp,lp); return 0;
	case WM_PAINT   : procPaint(hw,wp,lp) ; return 0;
	}
	return DefWindowProc(hw,msg,wp,lp);
}


(2) りサージュ図形

#include "myWin.h"
#include "math.h"
#define PI   3.14159265358979
#define SIZE 100
void Lissajous(HDC hdc){
	MoveToEx(hdc, SIZE*2+10, SIZE+10,NULL);
	for(int i=0;i<=360;i++){
		double A=PI*i/180;
		LineTo(hdc,
			(int)(SIZE*(cos(3*A)+1))+10,
			(int) (SIZE * (sin(5*A) +1)) + 10);  
	}
}
void procPaint(HWND hw, WPARAM wp,LPARAM lp){
	PAINTSTRUCT ps;RECT rect;
	HDC hdc=BeginPaint(hw, &ps); GetClientRect(hw,&rect);
	Lissajous(hdc);		
	EndPaint(hw,&ps);
}
LRESULT CALLBACK WndProc(HWND hw, UINT msg, WPARAM wp,LPARAM lp){
	switch(msg){
 	case WM_DESTROY : PostQuitMessage(0)  ; return 0;
	case WM_PAINT   : procPaint(hw,wp,lp) ; return 0;
	}
	return DefWindowProc(hw,msg,wp,lp);
}

(3) コッホ曲線

#include "myWin.h"
#include "math.h"
#define PI   3.14159265358979
static double curX,curY;static double Theta;
void t_pos(double X,double Y){ curX=X; curY=Y;}
void t_deg (double T){ Theta  =T;}
void t_turn(double T){ Theta +=T;}
void t_forward(HDC hdc,double length){
	double TH=Theta*PI/180;
	double X=curX+length*cos(TH);
	double Y=curY+length*sin(TH);
	MoveToEx(hdc,(int)curX, 100-(int)curY, NULL);
	LineTo  (hdc,(int)   X, 100-(int)   Y);
	curX=X; curY=Y;
}
void koch(HDC hdc,int n, double length){
	if(n<=0) t_forward(hdc,length);
	else{
		int nn=n-1;double len=length/3;
		koch(hdc,nn,len);t_turn(60); 
		koch(hdc,nn,len);t_turn(-120);
		koch(hdc,nn,len);t_turn(60);
		koch(hdc,nn,len);
	}
}
void procPaint(HWND hw, WPARAM wp,LPARAM lp){
	PAINTSTRUCT ps;
	HDC hdc=BeginPaint(hw, &ps); 
		t_pos(0,0);t_deg(0);
		koch(hdc,5,300);		
	EndPaint(hw,&ps);
}
LRESULT CALLBACK WndProc(HWND hw, UINT msg, WPARAM wp,LPARAM lp){
	switch(msg){
 	case WM_DESTROY : PostQuitMessage(0)  ; return 0;
	case WM_PAINT   : procPaint(hw,wp,lp) ; return 0;
	}
	return DefWindowProc(hw,msg,wp,lp);
}

2.6 ペンとブラシ

(1) ペンの作成

#include "myWin.h"
void procPaint(HWND hw, WPARAM wp,LPARAM lp){
	PAINTSTRUCT ps;
	HDC hdc=BeginPaint(hw,&ps);
	HPEN hpen=CreatePen(PS_DASH,1,0xFF0000);
	SelectObject(hdc, hpen);
	Rectangle(hdc,20,20,100,60);
	DeleteObject(hpen);
	EndPaint(hw,&ps);
}
LRESULT CALLBACK WndProc(HWND hw, UINT msg, WPARAM wp,LPARAM lp){
	switch(msg){
 	case WM_DESTROY : PostQuitMessage(0); return 0;
	case WM_PAINT:procPaint(hw, wp, lp);
	}
	return DefWindowProc(hw,msg,wp,lp);
}

(2) CreatePenIndirectを使う

#include "myWin.h"
Static LOGPEN logpen;
void procCreate(HWND hw, WPARAM wp,LPARAM lp){
	logpen.lopnStyle	= PS_SOLID;
	logpen.lopnWidth.x	= 4;
	logpen.lopnColor	= 0xFF;
}
void procPaint(HWND hw, WPARAM wp,LPARAM lp){
	PAINTSTRUCT ps;
	HDC hdc=BeginPaint(hw,&ps);
	SelectObject(hdc,CreatePenIndirect(&logpen));
	Rectangle(hdc,20,20,100,60);
	DeleteObject(SelectObject(hdc,GetStockObject(BLACK_PEN));
	EndPaint(hw,&ps);
}
LRESULT CALLBACK WndProc(HWND hw, UINT msg, WPARAM wp,LPARAM lp){
	switch(msg){
 	case WM_DESTROY: PostQuitMessage(0); return 0;
	case WM_CREATE : procCreate(hw, wp, lp);
	case WM_PAINT  : procPaint(hw, wp, lp);
	}
	return DefWindowProc(hw,msg,wp,lp);
}

(3) ブラシ

【procPaintのみ】

void procPaint(HWND hw, WPARAM wp,LPARAM lp){
	PAINTSTRUCT ps;
	HDC hdc=BeginPaint(hw,&ps);
	SelectObject(hdc,CreateSolidBrush(0xFF));
	Rectangle(hdc, 10, 10,200,100);
	DeleteObject(SelectObject(hdc,CreateSolidBrush(0xFF00)));
	Rectangle(hdc,30,30,240,60);
	DeleteObject(SelectObject(hdc,GetStockObject(WHITE_BRUSH)));
	EndPaint(hw,&ps);
}

【procPaintのみ】

void procPaint(HWND hw){
	PAINTSTRUCT ps;
	HDC hdc=BeginPaint(hw,&ps);
	HPEN hpen = CreatePen(PS_SOLID,4,0xFF) ;SelectObject(hdc,hpen);
	HBRUSH hbrush = CreateHatchBrush(HS_DIAGCROSS,0XFF00);
	SelectObject(hdc,hbrush); Rectangle(hdc, 10, 10,200,100);	
	DeleteObject(hbrush);
	hbrush = CreateHatchBrush(HS_CROSS,0XFF0000);
	SelectObject(hdc,hbrush); Ellipse(hdc, 20, 20,240,80); 
	DeleteObject(hbrush);
	DeleteObject(hpen);
	EndPaint(hw,&ps);
}

(4) ビットマップブラシ


【myBitmap.rcの内容】"myBitmap.bmp"は32×32のビットマップ

myBitmap BITMAP "myBitmap.bmp"


【ソースプログラム】

//ビットマップブラシ
#include <Windows.h>
static HBITMAP hB;   // ビットマップハンドル
static HBRUSH hBack; // パターンブラシのハンドル
LRESULT CALLBACK WndProc(HWND hw, UINT msg, WPARAM wp,LPARAM lp){
	switch(msg){
 	case WM_DESTROY : PostQuitMessage(0)  ; return 0;
	}
	return DefWindowProc(hw,msg,wp,lp);
}
BOOL initApp(HINSTANCE hCurI){
	WNDCLASS wc;
	hB    = LoadBitmap(hCurI,TEXT("myBitmap"));// ビットマップロード
	hBack = CreatePatternBrush(hB);            // ブラシ生成
	wc.style	= CS_HREDRAW | CS_VREDRAW|CS_DBLCLKS;
	wc.lpfnWndProc	= WndProc;
	wc.cbClsExtra	= wc.cbWndExtra=0;
	wc.hInstance	= hCurI;
	wc.hIcon	= LoadIcon(NULL,IDI_APPLICATION);
	wc.hCursor	= LoadCursor(NULL, IDC_ARROW);
	wc.hbrBackground= hBack;     // 生成したブラシを背景用とする
	wc.lpszMenuName	= NULL;
	wc.lpszClassName= TEXT("クラス名");
	return RegisterClass(&wc);
}
HWND initInst(HINSTANCE hCurI){
	HWND hw;
	hw=CreateWindow(TEXT("クラス名"),TEXT("こんばんは"),
		WS_OVERLAPPEDWINDOW | WS_VISIBLE,
		CW_USEDEFAULT,CW_USEDEFAULT,CW_USEDEFAULT,CW_USEDEFAULT,
		NULL,NULL,hCurI,NULL);
	return hw;
}
int WINAPI WinMain(HINSTANCE hCurI, HINSTANCE hPreI, PSTR lp, int cmd){
	MSG msg;
	if(!initApp(hCurI))       return 0;
	if(initInst(hCurI)==NULL) return 0;
	while(GetMessage(&msg,NULL,0,0)){
		TranslateMessage(&msg);
		DispatchMessage(&msg);
	}
	DeleteObject(hB);// リソース解放
	DeleteObject(hBack);
	return msg.wParam;
}

2.7 ラスタオペレーション

(2) ラスタオペレーションの例

#include "myWin.h"
void procPaint(HWND hw){
	PAINTSTRUCT ps;HBRUSH h1;
	HDC hdc=BeginPaint(hw,&ps);
	h1= CreateSolidBrush(0xFF0000);SelectObject(hdc,h1);
	Ellipse(hdc,10,10,200,100); DeleteObject(h1); 
	SetROP2(hdc,R2_XORPEN);       //ラスタオペレーションの指定
	h1= CreateSolidBrush(0xFF); SelectObject(hdc,h1);
	Rectangle(hdc,100,30,240,80); DeleteObject(h1);
	EndPaint(hw,&ps);
}
LRESULT CALLBACK WndProc(HWND hw, UINT msg, WPARAM wp,LPARAM lp){
	switch(msg){
 	case WM_DESTROY : PostQuitMessage(0); return 0;
	case WM_PAINT   : procPaint(hw)     ; return 0;
	}
	return DefWindowProc(hw,msg,wp,lp);
}

2.8 ビットマップの表示

(1) 原寸大の表示

【suzume.rcの内容】
suzume BITMAP "suzume.bmp"

【ソースプログラム】
#include "myWin.h"
static HBITMAP hB; 
void procCreate(HWND hw, WPARAM wp,LPARAM lp){
	hB=LoadBitmap(((LPCREATESTRUCT)lp)->hInstance, TEXT("suzume"));
}
void procPaint(HWND hw, WPARAM wp,LPARAM lp){
	PAINTSTRUCT ps;	
	HDC hdc  = BeginPaint(hw,&ps);
	HDC hBuff= CreateCompatibleDC(hdc);
	SelectObject(hBuff,hB);
	BitBlt(hdc,10,10,1000,600,hBuff,0,0,SRCCOPY);
	DeleteDC(hBuff);
	EndPaint(hw,&ps);
}
LRESULT CALLBACK WndProc(HWND hw, UINT msg, WPARAM wp,LPARAM lp){
	switch(msg){
 	case WM_DESTROY : PostQuitMessage(0)  ; return 0;
	case WM_CREATE  : procCreate(hw,wp,lp); return 0;
	case WM_PAINT   : procPaint (hw,wp,lp); return 0;
	}
	return DefWindowProc(hw,msg,wp,lp);
}

(2) 伸縮表示

//ビットマップの表示（ストレッチ)
#include "myWin.h"
#define SCALE 2 //縮小率
static HBITMAP hB; static BITMAP  bB;
void procCreate(HWND hw, WPARAM wp,LPARAM lp){
	hB=LoadBitmap(((LPCREATESTRUCT)lp)->hInstance, TEXT("suzume"));
	GetObject(hB,sizeof(BITMAP),&bB);
}
void procPaint(HWND hw, WPARAM wp,LPARAM lp){
	PAINTSTRUCT ps;	RECT rect;
	HDC hdc  = BeginPaint(hw,&ps);GetClientRect(hw,&rect);
		HDC hBuff= CreateCompatibleDC(hdc);
		SelectObject(hBuff,hB);
		SetStretchBltMode(hdc,COLORONCOLOR);
		StretchBlt(hdc,
			rect.right /2 - bB.bmWidth /(SCALE*2),
			rect.bottom/2 - bB.bmHeight/(SCALE*2),
			bB.bmWidth/SCALE, bB.bmHeight/SCALE,
			hBuff,0,0,
			bB.bmWidth, bB.bmHeight,SRCCOPY);
		DeleteDC(hBuff);
	EndPaint(hw,&ps);
}
(以下，WndProc以降省略)


2.9 その他の描画


(1) 多角形塗りつぶしモード

#include "myWin.h"
static POINT P1[5]={{100,10},{120,90},{70,40},{130,40},{80,90}};
static POINT P2[5];
void procCreate(HWND hw, WPARAM wp,LPARAM lp){
	for(int i=0;i<5;i++){P2[i].x=P1[i].x+100; P2[i].y=P1[i].y;}
}
void procPaint(HWND hw, WPARAM wp,LPARAM lp){
	PAINTSTRUCT ps;
	HDC hdc=BeginPaint(hw,&ps);
	HBRUSH hbrush=CreateSolidBrush(0xFF);
	SelectObject(hdc, hbrush);
	SetPolyFillMode(hdc,WINDING);
	Polygon(hdc,P1,5);
	SetPolyFillMode(hdc,ALTERNATE); 
	Polygon(hdc,P2,5);
	DeleteObject(hbrush);
	EndPaint(hw,&ps);
}
(以下，WndProc以降省略)

(2) ビットマップに描画

#include <Windows.h>
static HDC hBuff; static HBITMAP hBM;
void procCreate(HWND hw, WPARAM wp,LPARAM lp){
	HDC hdc=GetDC(hw); hBM=CreateCompatibleBitmap(hdc,1000,600);
	hBuff=CreateCompatibleDC(hdc); SelectObject(hBuff,hBM);
	SelectObject(hBuff,GetStockObject(NULL_PEN));
	PatBlt(hBuff,0,0,1000,600,WHITENESS);
	ReleaseDC(hw,hdc);
}
void procMouseMove(HWND hw, WPARAM wp,LPARAM lp){
	if(GetKeyState(VK_LBUTTON)<0){ 
		SelectObject(hBuff,CreateSolidBrush(0xFF));
		Ellipse(hBuff,LOWORD(lp)-2, HIWORD(lp)-2, 
		LOWORD(lp)+2, HIWORD(lp)+2);
		DeleteObject(SelectObject(hBuff,GetStockObject(WHITE_BRUSH)));
		InvalidateRect(hw,NULL,FALSE);
	}
}
void procPaint(HWND hw,WPARAM wp,LPARAM lp){
	PAINTSTRUCT ps;	HDC hdc=BeginPaint(hw,&ps);
	BitBlt(hdc,0,0,1000,600,hBuff,0,0,SRCCOPY);
	EndPaint(hw,&ps);
}
LRESULT CALLBACK WndProc(HWND hw, UINT msg, WPARAM wp,LPARAM lp){
	switch(msg){
	case WM_DESTROY  :	DeleteDC(hBuff);DeleteObject(hBM); 
				PostQuitMessage(0)     ; return 0;
	case WM_CREATE   :	procCreate(hw,wp,lp)   ; return 0;
	case WM_MOUSEMOVE:	procMouseMove(hw,wp,lp); return 0;	
	case WM_PAINT    :	procPaint(hw,wp,lp)    ; return 0;
	}
	return DefWindowProc(hw,msg,wp,lp);
}

(3) リージョン


BOOL FrameRgn(HDC hdc, HRGN hrgn, HBRUSH hbr, int nWidth, int nHight)；
void procPaint(HWND hw, WPARAM wp,LPARAM lp){
	PAINTSTRUCT ps;	
	HDC hdc=BeginPaint(hw,&ps);
	HRGN hrg=CreateRoundRectRgn(10,10,200,100,10,10);
	SelectObject(hdc,CreateHatchBrush(HS_DIAGCROSS,RGB(0,0,0xFF)));
	PaintRgn(hdc,hrg);
	FrameRgn(hdc,hrg, (HBRUSH)GetStockObject(GRAY_BRUSH),3,10);
	DeleteObject(hrg);
	DeleteObject(SelectObject(hdc,GetStockObject(BLACK_BRUSH)));
	EndPaint(hw,&ps);
}
(WndProc以降省略)

【リージョン内だけを再描画】

void procLeftButtonDown(HWND hw, WPARAM wp,LPARAM lp){
	HDC hdc=GetDC(hw); SelectObject(hdc,GetStockObject(WHITE_PEN));
	Rectangle(hdc,0,0,210,110);
	HRGN hrg=CreateRoundRectRgn(10,10,200,100,10,10);
	SelectObject(hdc,CreateHatchBrush(HS_DIAGCROSS,RGB(0,0,0xFF)));
	PaintRgn(hdc,hrg);
	FrameRgn(hdc,hrg, (HBRUSH)GetStockObject(GRAY_BRUSH),3,10);
	InvalidateRgn(hw,hrg,FALSE);
	DeleteObject(hrg);
	DeleteObject(SelectObject(hdc,GetStockObject(BLACK_BRUSH)));
	ReleaseDC(hw,hdc);
}
void procPaint(HWND hw, WPARAM wp,LPARAM lp){
	PAINTSTRUCT ps; TCHAR str[10];	HDC hdc=BeginPaint(hw,&ps);
	SelectObject(hdc,GetStockObject(BLACK_BRUSH));
	Ellipse(hdc,0,0,50,50);	EndPaint(hw,&ps);
}
LRESULT CALLBACK WndProc(HWND hw, UINT msg, WPARAM wp,LPARAM lp){
	switch(msg){
 	case WM_DESTROY     : PostQuitMessage(0)          ; return 0;
	case WM_LBUTTONDOWN : procLeftButtonDown(hw,wp,lp); return 0;
	case WM_PAINT       : procPaint(hw,wp,lp)         ; return 0;
	}
	return DefWindowProc(hw,msg,wp,lp);
}