我正在使用SetTimer在我的游戏中放置一个定时器,定时器会每1000毫秒触发一段时间后,我想改变定时器的时间间隔,所以我再次调用SetTimer与相同的timerId(根据MSDN,这将取代旧超时计时器),但它似乎不起作用,计时器没有被解雇。SetTimer不改变时间间隔
这是我的代码,这是一个典型的游戏循环。
INT WINAPI wWinMain(HINSTANCE hInstance, HINSTANCE hPrevInstance, LPWSTR szCmdLine, int iCmdShow)
{
WNDCLASSEX winClass ;
winClass.lpszClassName = L"RotationBySetTimer";
winClass.cbSize = sizeof(WNDCLASSEX);
winClass.style = CS_HREDRAW | CS_VREDRAW;
winClass.lpfnWndProc = MsgProc;
winClass.hInstance = hInstance;
winClass.hIcon = NULL ;
winClass.hIconSm = NULL ;
winClass.hCursor = LoadCursor(NULL, IDC_ARROW) ;
winClass.hbrBackground = NULL ;
winClass.lpszMenuName = NULL ;
winClass.cbClsExtra = 0;
winClass.cbWndExtra = 0;
RegisterClassEx (&winClass) ;
HWND hWnd = CreateWindowEx(NULL,
winClass.lpszClassName, // window class name
L"RotationBySetTimer", // window caption
WS_OVERLAPPEDWINDOW, // window style
32, // initial x position
32, // initial y position
600, // initial window width
600, // initial window height
NULL, // parent window handle
NULL, // window menu handle
hInstance, // program instance handle
NULL) ; // creation parameters
**SetTimer(hWnd, 1, 1000, NULL);**
// Initialize Direct3D
if(SUCCEEDED(InitD3D(hWnd)))
{
// Show the window
ShowWindow(hWnd, SW_SHOWDEFAULT);
UpdateWindow(hWnd);
MSG msg ;
ZeroMemory(&msg, sizeof(msg));
PeekMessage(&msg, NULL, 0U, 0U, PM_NOREMOVE);
// Get last time
static DWORD lastTime = timeGetTime();
while (msg.message != WM_QUIT)
{
if(PeekMessage(&msg, NULL, 0U, 0U, PM_REMOVE) != 0)
{
TranslateMessage (&msg) ;
DispatchMessage (&msg) ;
}
else // Render the game if there is no message to process
{
// Get current time
DWORD currTime = timeGetTime();
// Calculate time elapsed
float timeDelta = (currTime - lastTime) * 0.001f;
// Render
Render(hWnd, timeDelta) ;
// Update last time to current
lastTime = currTime;
}
}
}
UnregisterClass(winClass.lpszClassName, hInstance) ;
return 0;
}
我在Render函数中再次调用SetTimer来更改时间间隔。
void Render(HWND hWnd, float timeDelta)
{
**SetTimer(hWnd, 1, 2000, NULL);**
if (!g_bActive)
{
Sleep(50) ;
}
SetupMatrix() ;
// Clear the back-buffer to a RED color
g_pd3dDevice->Clear(0, NULL, D3DCLEAR_TARGET, D3DCOLOR_XRGB(0,0,0), 1.0f, 0);
// Begin the scene
if(SUCCEEDED(g_pd3dDevice->BeginScene()))
{
// Draw teapot
g_pTeapotMesh->DrawSubset(0) ;
// End the scene
g_pd3dDevice->EndScene();
}
// Present the back-buffer contents to the display
g_pd3dDevice->Present(NULL, NULL, NULL, NULL);
}
代码工作好之前,我在SetTimer的再次调用渲染功能,但加入这一行,为什么后停止工作?
为了让您收到'WM_TIMER'消息,您的代码必须抽取消息循环。如果您陷入计算密集的渲染中,并不会定期停止抽取消息循环,则无论计时器的间隔如何,都不会收到“WM_TIMER”消息。如果你注释掉第二次调用SetTimer,你实际上是否每1000毫秒收到一次WM_TIMER消息? – 2013-05-11 08:26:36
是的,当我将第二个调用注释到SetTimer时,它就可以工作。 – zdd 2013-05-11 11:47:31