46.矩操作函數SetRect、FillRect、FrameRect、PtInRect、InvertRect、Offsetrect、SetRectEmpty、IsRectEmpty、Intersect

先把這兩個定義給弄清除 INT_PTR CALLBACK

typedef __int64 INT_PTR, *PINT_PTR;
#define CALLBACK    __stdcall
           

FillRect 填充矩形區域

WINUSERAPI
int
WINAPI
FillRect(
    __in HDC hDC,
    __in CONST RECT *lprc, //要填充的矩形區域
    __in HBRUSH hbr //畫筆，這裡的畫筆可以不用選入DC直接填充,
    );
           

SetRect設定矩形區域的範圍，可以直接用左上和右下四個點設定矩形區域的範圍

WINUSERAPI
BOOL
WINAPI
SetRect(
    __out LPRECT lprc, //要設定的對象
    __in int xLeft,
    __in int yTop,
    __in int xRight,
    __in int yBottom);
           

FrameRect 指定的畫刷為指定的矩形畫邊框。邊框的寬和高總是一個邏輯單元。

WINUSERAPI
int
WINAPI
FrameRect(
    __in HDC hDC,
    __in CONST RECT *lprc,
    __in HBRUSH hbr);
           

InvertRect 對矩形區域内的顔色進行取反操作 （函數通過對矩形内部的像素點進行邏輯NOT操作而将視窗中的矩形反轉。）

WINUSERAPI
BOOL
WINAPI
InvertRect(
    __in HDC hDC,
    __in CONST RECT *lprc);
           

OffsetRect 對矩形區域進行偏移，偏移distancex和distancey長度

WINUSERAPI
BOOL
WINAPI
OffsetRect(
    __inout LPRECT lprc,
    __in int dx,
    __in int dy);
           

SetRectEmpty 将矩形lpRect設為一個空矩形

IsRectEmpty 矩形區域是否為空

WINUSERAPI
BOOL
WINAPI
SetRectEmpty(
    __out LPRECT lprc);

WINUSERAPI
BOOL
WINAPI
SetRectEmpty(
    __out LPRECT lprc);
           

InflateRect函數增大或減小指定矩形的寬和高。InflateRect函數在矩形的左和右增加dx,在矩形的上下增加dy。 dx和dy參數是有符号值。正數增加寬和高，負數減小。

WINUSERAPI
BOOL
WINAPI
InflateRect(
    __inout LPRECT lprc,
    __in int dx,
    __in int dy);
           

GetClientRect、GetWindowRect 獲得窗體的矩形區域

長為rect.right,高為rect.bottom

WINUSERAPI
BOOL
WINAPI
GetClientRect(
    __in HWND hWnd,
    __out LPRECT lpRect);

WINUSERAPI
BOOL
WINAPI
GetWindowRect(
    __in HWND hWnd,
    __out LPRECT lpRect);
           

IntersectRect獲得兩個矩形的相交區域

UnionRect獲得兩個矩形合并區域

//相交兩個矩形區域
WINUSERAPI
BOOL
WINAPI
IntersectRect(
    __out LPRECT lprcDst,
    __in CONST RECT *lprcSrc1,
    __in CONST RECT *lprcSrc2);
//合并兩個矩形區域
WINUSERAPI
BOOL
WINAPI
UnionRect(
    __out LPRECT lprcDst,
    __in CONST RECT *lprcSrc1,
    __in CONST RECT *lprcSrc2);
           

PtInRect點是否在矩形區域内

WINUSERAPI
BOOL
WINAPI
PtInRect(
    __in CONST RECT *lprc,
    __in POINT pt);
           

在這裡程式設計的時候，學習到一個小技巧

DlgMainProc消息處理函數的最後一個參數，LPARAM lParam是傳遞了滑鼠的指針

POINT pt;

pt.x = LOWORD（lParam）;獲得滑鼠的x點

pt.y = HIWORD（lParam）;獲得滑鼠的y點

下面是我寫的代碼

#include <Windows.h>
#include "resource.h"

INT_PTR CALLBACK DlgMainProc(HWND hWnd,UINT uMsg,WPARAM wParam,LPARAM lParam)
{
	BOOL bRet = true;
	HDC hdc;
	PAINTSTRUCT ps;
	static int ix = 10;
	static int iy = 10;
	HBRUSH hBrush;
	TCHAR szBuffer[256];

	DWORD isEmpty;

	RECT rect;
	RECT rect_dest1,rect_dest2;
	RECT rect_src1,rect_src2;
	
	int wmId,b;
	POINT pt;

	switch(uMsg)
	{
	case WM_COMMAND:
		wmId = LOWORD(wParam);
		b = HIWORD(wParam);
		switch(wmId)
		{
		case IDC_BUTTON1:
			isEmpty = IsRectEmpty(&rect);
			wsprintf(szBuffer,TEXT("SetRectEmpty:\nx = %d \ny = %d \nIsRectEmpty:%d\n"),rect.left,rect.top,isEmpty);
			MessageBox(hWnd,szBuffer,TEXT("test"),MB_OK);
			break;
		case IDC_BUTTON2:
			EndDialog(hWnd,0);
			break;
		default:
			return DefWindowProc(hWnd,uMsg,wParam,lParam);
		}
		break;
	case WM_CLOSE:
		EndDialog(hWnd,0);
		break;
	case WM_PAINT:
		hdc = BeginPaint(hWnd,&ps);

		SetRect(&rect,ix,iy,ix+100,iy+100);
		FillRect(hdc,&rect,(HBRUSH)GetStockObject(GRAY_BRUSH ));
		
		SetRect(&rect,ix*2+100,iy,ix*2+200,iy+100);
		FrameRect(hdc,&rect,(HBRUSH)GetStockObject(BLACK_BRUSH));
		
		SetRect(&rect,ix*3+200,iy,ix*3+300,iy+100);
		hBrush = CreateSolidBrush(RGB(0,255,255));
		SelectObject(hdc,(HBRUSH)hBrush);
		Rectangle(hdc,rect.left,rect.top,rect.right,rect.bottom);
		InvertRect(hdc,&rect);
		OffsetRect(&rect,50,50);
		//SetRect(&rect,ix*3+250,iy,ix*3+350,iy+100);
		InvertRect(hdc,&rect);

		OffsetRect(&rect,100,100);
		OffsetRect(&rect,-320,10);
		InflateRect(&rect,50,50);

		FrameRect(hdc,&rect,(HBRUSH)GetStockObject(LTGRAY_BRUSH));

		//SetRectEmpty(&rect);
		
		isEmpty = IsRectEmpty(&rect);
		wsprintf(szBuffer,TEXT("SetRectEmpty:\nx = %d \ny = %d \nIsRectEmpty:%d\n"),rect.left,rect.top,isEmpty);
		//MessageBox(NULL,szBuffer,TEXT("test"),MB_OK);
		
		GetClientRect(hWnd,&rect);

		SetRect(&rect_src1,rect.right-200,rect.bottom-200,rect.right-10,rect.bottom-10);
		SetRect(&rect_src2,rect.right-300,rect.bottom-300,rect.right-110,rect.bottom-110);
		IntersectRect(&rect_dest1,&rect_src1,&rect_src2);
		UnionRect(&rect_dest2,&rect_src1,&rect_src2);
		

		FillRect(hdc,&rect_src1,(HBRUSH)GetStockObject(BLACK_BRUSH));
		FillRect(hdc,&rect_src2,(HBRUSH)GetStockObject(WHITE_BRUSH));
		FillRect(hdc,&rect_dest1,(HBRUSH)GetStockObject(DKGRAY_BRUSH));
		FrameRect(hdc,&rect_dest2,(HBRUSH)GetStockObject(DKGRAY_BRUSH));
		
		
		
		EndPaint(hWnd,&ps);
		break;
	case WM_LBUTTONDOWN:

		break;
	case WM_MOUSEMOVE:
		GetClientRect(hWnd,&rect);
		rect.left = rect.right-200;
		rect.top = rect.bottom-200;

		pt.x = LOWORD(lParam);
		pt.y = HIWORD(lParam);
		if(PtInRect(&rect,pt))
		{
			MessageBox(hWnd,TEXT("滑鼠移動到選擇區域了"),TEXT("測試"),MB_OK);
		}
		break;
	default:
		bRet = false;
		break;
	}


	return bRet;

}

int APIENTRY WinMain(HINSTANCE hInstance,
	HINSTANCE hPrevInstance,
	LPSTR szCmdLine,
	int nCmdLine)
{
	DialogBox(hInstance,MAKEINTRESOURCE(IDD_DIALOG1),NULL,DlgMainProc);
	return 0;
}