【发布时间】:2012-04-01 22:31:12
【问题描述】:
所以我正在尝试使用 Windows API(和 DirectX9,如果重要的话)制作程序,并尝试使用 WM_KEYDOWN 和 WM_KEYUP 从键盘获取输入。这是我现在代码的相关部分。这个想法是“keyTimes”数组应该存储一个键被按下的帧数。
LRESULT CALLBACK WndProc(HWND, UINT, WPARAM, LPARAM);
Game* Game::s_instance = NULL;
LPDIRECT3D9 d3dObject;
LPDIRECT3DDEVICE9 d3dDevice;
Game::Game(){
for(int i=0; i<256; i++){
keyTimes[i]=0;
}
}
//....
Game* Game::Instance(){
if(Game::s_instance==NULL){
s_instance = new Game();
}
return s_instance;
}
//Checks to see if key was pressed, and adds to value
void Game::keyCheck(int keyNum, bool pressed){
if(pressed){
keyTimes[keyNum]++;
}
else{
keyTimes[keyNum]=0;
}
}
//Returns time that key has been pressed
int Game::keyPressed(int keyNum){
return keyTimes[keyNum];
}
//Returns true if key was hit once, and doesn't return true again until the key is let go and hit again.
bool Game::keyHit(int keyNum){
return keyTimes[keyNum]==1;
}
//Returns true only if the key has been held for delay
bool Game::keyHeld(int keyNum, int delay){
if(delay==0)
delay=1;
return keyTimes[keyNum]==delay;
}
//Returns true everyXFrame frames.
bool Game::keyPressedDelay(int keyNum, int everyXFrame){
if(everyXFrame<2){
return false;
}
return keyTimes[keyNum]%everyXFrame==1;
}
LRESULT CALLBACK WndProc(HWND hWnd, UINT message, WPARAM wParam, LPARAM lParam){
switch (message)
{
case WM_DESTROY:
PostQuitMessage(0);
break;
case WM_KEYDOWN:
{
Game::Instance()->keyCheck(wParam,true);
return 0;
}
break;
case WM_KEYUP:
{
Game::Instance()->keyCheck(wParam,false);
return 0;
}
break;
default:
return DefWindowProc(hWnd, message, wParam, lParam);
}
return 0;
}
//........
//Inside the main function while loop....
if(Game::Instance()->keyHit(VK_LEFT)){
thing->move(-3,0);
}
if(Game::Instance()->keyHit(VK_RIGHT)){
thing->move(3,0);
}
if(Game::Instance()->keyHit(VK_UP)){
thing->move(0,-3);
}
if(Game::Instance()->keyHit(VK_DOWN)){
thing->move(0,3);
}
//.......
因此,当我尝试使用“KeyPressed”函数作为布尔值来移动主函数中的“事物”时,它会移动三个像素,停止大约半秒,然后再次开始移动。如果我在按住第一个键的同时尝试按下另一个键,它也会再次停止。当我使用“KeyHit”移动它时,它会移动大约 9-12 个像素,然后停止(而不是只移动 3 个像素)。
我将如何更改我的代码,以使函数按照注释的方式工作,没有任何延迟?
编辑 3/26/12:我已设法修复代码。事实证明,问题只是我在我的主循环中使用了 GetMessage 函数,它在移动之前等待输入,而我应该一直使用 PeekMessage。
【问题讨论】:
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也许
WM_MOVEUP(或类似的)消息将有助于解决问题,如果您在密钥关闭时继续发送它。非系统定义的消息有指定的消息范围。