为什么屏幕刷新的速度这么慢?

[y_zhi_yong]

我有一程序,想实现随机的画图操作,但是屏幕重画的速度特别慢.还请各位高手指点.代码如下.
#include <windows.h>
#include "time.h"

#define DIVISIONS 5
#define MoveTo(hdc, x, y) MoveToEx (hdc, x, y, NULL)

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

int WINAPI WinMain (HINSTANCE hInstance, HINSTANCE hPrevInstance,
PSTR szCmdLine, int iCmdShow)
{
static char szAppName[] = "Checker1" ;
HWND hwnd ;
MSG msg ;
WNDCLASSEX wndclass ;

wndclass.cbSize = sizeof (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 ;
wndclass.hIconSm = LoadIcon (NULL, IDI_APPLICATION) ;

RegisterClassEx (&wndclass) ;

hwnd = CreateWindow (szAppName, "Checker1 Mouse Hit-Test Demo",
WS_OVERLAPPEDWINDOW,
CW_USEDEFAULT, CW_USEDEFAULT,
CW_USEDEFAULT, CW_USEDEFAULT,
NULL, NULL, hInstance, NULL) ;

ShowWindow (hwnd, iCmdShow) ;
SetTimer(hwnd,1,1000,NULL);
UpdateWindow (hwnd) ;


while (GetMessage (&msg, NULL, 0, 0))
{
TranslateMessage (&msg) ;
DispatchMessage (&msg) ;
}
KillTimer(hwnd,1);
return msg.wParam ;
}

LRESULT CALLBACK WndProc (HWND hwnd, UINT iMsg, WPARAM wParam, LPARAM lParam)
{
static BOOL fState[DIVISIONS][DIVISIONS] ;
static int cxBlock, cyBlock ;
HDC hdc ;
PAINTSTRUCT ps ;
RECT rect ;
int x, y ;
static int m,n;

switch (iMsg)
{
case WM_SIZE :
cxBlock = LOWORD (lParam) / DIVISIONS ;
cyBlock = HIWORD (lParam) / DIVISIONS ;
return 0 ;

case WM_TIMER:
hdc=GetDC(hwnd);
srand(unsigned(time(NULL)));
m=rand()%5;
n=rand()%5;

fState[m][n]=1;

InvalidateRect(hwnd,NULL,false);
return 0;


case WM_LBUTTONDOWN :
x = LOWORD (lParam) / cxBlock ;
y = HIWORD (lParam) / cyBlock ;

if(m==x && n==y)
MessageBeep(0);
else
MessageBeep(MB_ICONHAND);
return 0 ;


case WM_PAINT :
hdc = BeginPaint (hwnd, &ps) ;

for (x = 0 ; x < DIVISIONS ; x++)
for (y = 0 ; y < DIVISIONS ; y++)
{
Rectangle(hdc,x*cxBlock,y*cyBlock,(x+1)*cxBlock,(y+1)*cyBlock);

if (fState [m][n])
{
MoveTo (hdc, m * cxBlock, n * cyBlock) ;
LineTo (hdc, (m+1) * cxBlock, (n+1) * cyBlock) ;
MoveTo (hdc, m * cxBlock, (n+1) * cyBlock) ;
LineTo (hdc, (m+1) * cxBlock, n * cyBlock) ;
}
}

EndPaint (hwnd, &ps) ;
return 0 ;

case WM_DESTROY :
PostQuitMessage (0) ;
return 0 ;
}
return DefWindowProc (hwnd, iMsg, wParam, lParam) ;
}

[virtualfunction]

SetTimer(hwnd,1,1000,NULL);// 1秒钟刷新一次？

[y_zhi_yong]

我曾设置为0.5秒一次,10ms一次,但是刷新速度都比较慢.而且,间隔时间越短屏幕的晃动越厉害.

[dycdyc123]

这个？？

可能与自己的刷新率有关

你搞高点试试？