问题描述
- windows程序设计WM_ANISOTROPIC使用问题
-
#include#define NUMLINES ((int) (sizeof devcaps / sizeof devcaps [0]))
struct
{
int iIndex ;
TCHAR * szLabel ;
TCHAR * szDesc ;
}
devcaps [] =
{
HORZSIZE, TEXT ("HORZSIZE"), TEXT ("Width in millimeters:"),
VERTSIZE, TEXT ("VERTSIZE"), TEXT ("Height in millimeters:"),
HORZRES, TEXT ("HORZRES"), TEXT ("Width in pixels:"),
VERTRES, TEXT ("VERTRES"), TEXT ("Height in raster lines:"),
BITSPIXEL, TEXT ("BITSPIXEL"), TEXT ("Color bits per pixel:"),
PLANES, TEXT ("PLANES"), TEXT ("Number of color planes:"),
NUMBRUSHES, TEXT ("NUMBRUSHES"), TEXT ("Number of device brushes:"),
NUMPENS, TEXT ("NUMPENS"), TEXT ("Number of device pens:"),
NUMMARKERS, TEXT ("NUMMARKERS"), TEXT ("Number of device markers:"),
NUMFONTS, TEXT ("NUMFONTS"), TEXT ("Number of device fonts:"),
NUMCOLORS, TEXT ("NUMCOLORS"), TEXT ("Number of device colors:"),
PDEVICESIZE, TEXT ("PDEVICESIZE"), TEXT ("Size of device structure:"),
ASPECTX, TEXT ("ASPECTX"), TEXT ("Relative width of pixel:"),
ASPECTY, TEXT ("ASPECTY"), TEXT ("Relative height of pixel:"),
ASPECTXY, TEXT ("ASPECTXY"), TEXT ("Relative diagonal of pixel:"),
LOGPIXELSX, TEXT ("LOGPIXELSX"), TEXT ("Horizontal dots per inch:"),
LOGPIXELSY, TEXT ("LOGPIXELSY"), TEXT ("Vertical dots per inch:"),
SIZEPALETTE, TEXT ("SIZEPALETTE"), TEXT ("Number of palette entries:"),
NUMRESERVED, TEXT ("NUMRESERVED"), TEXT ("Reserved palette entries:"),
COLORRES, TEXT ("COLORRES"), TEXT ("Actual color resolution:")
} ;LRESULT CALLBACK WndProc (HWND, UINT, WPARAM, LPARAM) ;
int WINAPI WinMain (HINSTANCE hInstance, HINSTANCE hPrevInstance,
PSTR szCmdLine, int iCmdShow)
{
static TCHAR szAppName[] = TEXT ("DevCaps1") ;
HWND hwnd ;
MSG msg ;
WNDCLASS wndclass ;wndclass.style = CS_HREDRAW | CS_VREDRAW ; wndclass.lpfnWndProc = WndProc ; wndclass.cbClsExtra = 0 ; wndclass.cbWndExtra = 0 ; 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 ("This program requires Windows NT!"), szAppName, MB_ICONERROR) ; return 0 ; } hwnd = CreateWindow (szAppName, TEXT ("Device Capabilities"), WS_OVERLAPPEDWINDOW, CW_USEDEFAULT, CW_USEDEFAULT, CW_USEDEFAULT, CW_USEDEFAULT, NULL, NULL, hInstance, NULL) ; ShowWindow (hwnd, iCmdShow) ; UpdateWindow (hwnd) ; while (GetMessage (&msg, NULL, 0, 0)) { TranslateMessage (&msg) ; DispatchMessage (&msg) ; } return msg.wParam ;
}
LRESULT CALLBACK WndProc (HWND hwnd, UINT message, WPARAM wParam, LPARAM lParam)
{
static int cxChar, cxCaps, cyChar,x,y,cxClient,cyClient ;
TCHAR szBuffer[10] ;
HDC hdc ;
int i ;
PAINTSTRUCT ps ;
TEXTMETRIC tm ;switch (message) { case WM_CREATE: hdc = GetDC (hwnd) ; x=1000; y=1000; SetMapMode(hdc,MM_ANISOTROPIC); SetWindowExtEx(hdc,x,y,NULL); SetViewportExtEx(hdc,cxClient,-cyClient,NULL); SetViewportOrgEx(hdc,cxClient/2,cyClient/2,NULL); GetTextMetrics (hdc, &tm) ; cxChar = tm.tmAveCharWidth ; cxCaps = (tm.tmPitchAndFamily & 1 ? 3 : 2) * cxChar / 2 ; cyChar = tm.tmHeight + tm.tmExternalLeading ; ReleaseDC (hwnd, hdc) ; return 0 ; case WM_KEYDOWN: switch(wParam) { case VK_LEFT: x=x+50; y=y+50; InvalidateRect(hwnd,NULL,TRUE); UpdateWindow(hwnd); break; case VK_RIGHT: x=x-50; y=y-50; InvalidateRect(hwnd,NULL,TRUE); UpdateWindow(hwnd); break; } return 0; case WM_PAINT: hdc = BeginPaint (hwnd, &ps) ; SetMapMode(hdc,MM_ANISOTROPIC); SetWindowExtEx(hdc,x,y,NULL); SetViewportExtEx(hdc,cxClient,-cyClient,NULL); SetViewportOrgEx(hdc,cxClient/2,cyClient/2,NULL); for (i = 0 ; i < NUMLINES ; i++) { TextOut (hdc, 0, cyChar * i, devcaps[i].szLabel, lstrlen (devcaps[i].szLabel)) ; TextOut (hdc, 14 * cxCaps, cyChar * i, devcaps[i].szDesc, lstrlen (devcaps[i].szDesc)) ; SetTextAlign (hdc, TA_RIGHT | TA_TOP) ; TextOut (hdc, 14 * cxCaps + 35 * cxChar, cyChar * i, szBuffer, wsprintf (szBuffer, TEXT ("%5d"), GetDeviceCaps (hdc, devcaps[i].iIndex))) ; SetTextAlign (hdc, TA_LEFT | TA_TOP) ; } EndPaint (hwnd, &ps) ; return 0 ; case WM_DESTROY: PostQuitMessage (0) ; return 0 ; } return DefWindowProc (hwnd, message, wParam, lParam) ;
}
以上代码是程序代码,此代码大部分来自windows程序设计第四章的DevCaps1程序,我只是把
case WM_CREATE部分增加了代码
x=1000;
y=1000;
SetMapMode(hdc,MM_ANISOTROPIC);
SetWindowExtEx(hdc,x,y,NULL);
SetViewportExtEx(hdc,cxClient,-cyClient,NULL);
SetViewportOrgEx(hdc,cxClient/2,cyClient/2,NULL);
用于改变映射方式,另外增加了
case WM_KEYDOWN:
switch(wParam)
{
case VK_LEFT:
x=x+50;
y=y+50;
InvalidateRect(hwnd,NULL,TRUE);
UpdateWindow(hwnd);
break;
case VK_RIGHT:
x=x-50;
y=y-50;
InvalidateRect(hwnd,NULL,TRUE);
UpdateWindow(hwnd);
break;
}
return 0;
每次按下左箭头,映射模式下的逻辑坐标范围增加50,同时将整个窗口InvalidateRect,然后updatewindow
立刻更新窗口,右箭头是逻辑坐标范围缩小50,其余效果一样,最后case WM_PAINT在
BeginPaint函数后增加
SetMapMode(hdc,MM_ANISOTROPIC);
SetWindowExtEx(hdc,x,y,NULL);
SetViewportExtEx(hdc,cxClient,-cyClient,NULL);
SetViewportOrgEx(hdc,cxClient/2,cyClient/2,NULL);
也就是将减小或者增大的的逻辑坐标应用到此程序中,这个程序的执行情况应该是每次减小逻辑坐标
输出的文字应该变大,增加逻辑坐标输出的问题变小(因为我最开始设置映射模式时默认值为1000,
假如此时 GetTextMetrics 获得的cxChar和cyChar都为10,那么后面逻辑坐标变大并且应用到此程序
中,那么相对的cxChar和cyChar比例就缩小了,因为后面没有再调用GetTextMetrics函数,所以他们
一直为10,同理,逻辑坐标变小后应该放大,但实际运行情况是字体没有变小变大,但是每一段文字之间
的空格变大了,请问这是为什么,请知道的告诉下,谢谢了,这个问题纠结很久了)
解决方案
http://blog.sina.com.cn/s/blog_5cd4cccf0100pxh9.html