SetViewportOrgEx和SetWindowOrgEx

在MM_TEXT映射模式下使用这两个函数。

对于

BOOL SetViewportOrgEx(
HDC hdc, // 设备内容HANDLE
int X, // 新Viewport的x坐标
int Y, // 新Viewport的y坐标
LPPOINT lpPoint // 原来的Viewport的坐标
);

这样逻辑点(0,0)将映射到设备点(X,Y)，即(X,Y)成为了原点。

对于

BOOL SetWindowOrgEx(HDC hdc, int X, int Y, LPPOINT lpPoint)；

SetWindowOrgEx函数的参数总是以逻辑单位的形式给出

#include <Windows.h>
 
LRESULT CALLBACK WndProc(HWND, UINT, WPARAM, LPARAM);
 
int WINAPI WinMain(HINSTANCE hInstance, HINSTANCE hPrevInstance, PSTR szCmdLine, int iCmdShow)
{
    static TCHAR szAppName[] = TEXT("WNDCLASS NAME");
    HWND hwnd;
    MSG msg;
    WNDCLASS wndclass;
 
    wndclass.style = CS_HREDRAW | CS_VREDRAW;
    wndclass.lpfnWndProc = WndProc;
    wndclass.cbClsExtra = ;
    wndclass.cbWndExtra = ;
    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 = szAppName;
 
    if (!RegisterClass(&wndclass)) {
        MessageBox(NULL, TEXT("窗口创建失败！需要Windows NT！(传递消息为UNICODE)"), szAppName, MB_ICONERROR);
 
        return ;
    }
 
    hwnd = CreateWindow(
        szAppName,
        TEXT("Hk_Mayfly"),
        WS_OVERLAPPEDWINDOW,
        CW_USEDEFAULT,
        CW_USEDEFAULT,
        CW_USEDEFAULT,//宽度
        CW_USEDEFAULT,//高度
        NULL,
        NULL,
        hInstance,
        NULL
    );
    ShowWindow(hwnd, iCmdShow);
    UpdateWindow(hwnd);
 
    while (GetMessage(&msg, NULL, , )) {
        TranslateMessage(&msg);
        DispatchMessage(&msg);
    }
 
    return msg.wParam;
}
 
LRESULT CALLBACK WndProc(HWND hwnd, UINT message, WPARAM wParam, LPARAM lParam) {
    HDC hdc;
    PAINTSTRUCT ps;
    static int iMapMode;
    TCHAR szBuffer[] = L"Hk_Mayfly!!!!？";
    static int cxClient, cyClient;
 
    switch (message) {
    case WM_SIZE:
        cxClient = LOWORD(lParam);
        cyClient = HIWORD(lParam);
        return ;
    case WM_PAINT:
        hdc = BeginPaint(hwnd, &ps);
        //
        TextOut(hdc, , , TEXT("●"), );
        SelectObject(hdc, CreateSolidBrush(RGB(, , )));//蓝色
        Ellipse(hdc, , , , );
        SelectObject(hdc, CreateSolidBrush(RGB(,,)));//绿色
        Ellipse(hdc, cxClient - , cyClient - , cxClient, cyClient);
 
        //2
        //SetViewportOrgEx(hdc, cxClient / 2, cyClient / 2, NULL);//将逻辑点(0,0)映射到设备点(cxClient / 2,cyClient / 2),即将(cxClient / 2,cyClient / 2)作为(0,0)点
        /*TextOut(hdc, 0, 0, TEXT("●"), 1);
        SelectObject(hdc, CreateSolidBrush(RGB(0, 245, 255)));
        Ellipse(hdc, 0, 0, 100, 100);
        SelectObject(hdc, CreateSolidBrush(RGB(67, 205, 128)));
        Ellipse(hdc, cxClient - 100, cyClient - 100, cxClient, cyClient);*/
 
        //
        /*将逻辑点(cxClient / 2,cyClient / 2)映射到设备点(0,0),将(0,0)点作为(0,200)*/
        /*SetWindowOrgEx(hdc, cxClient / 2, cyClient / 2, NULL);
        TextOut(hdc, 0, 0, TEXT("●"), 1);
        SelectObject(hdc, CreateSolidBrush(RGB(0, 245, 255)));
        Ellipse(hdc, 0, 0, 100, 100);
        SelectObject(hdc, CreateSolidBrush(RGB(67, 205, 128)));
        Ellipse(hdc, cxClient - 100, cyClient - 100, cxClient, cyClient);*/
        EndPaint(hwnd, &ps);
        return ;
    case WM_DESTROY:
        PostQuitMessage();
        return ;
    }
    return DefWindowProc(hwnd, message, wParam, lParam);
}

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