INPUT.C

/*========================================================================== 
 * 
 *  Copyright (C) 1995-1997 Microsoft Corporation. All Rights Reserved. 
 * 
 *  File:       input.c 
 *  Content:    DirectInput functionality for Multi-player duel 
 * 
 * 
 ***************************************************************************/ 
 
 
#include "input.h" 
#include "gameproc.h" 
 
extern HINSTANCEghinst;// program instance 
extern HWND                     ghWndMain;              // app window handle 
 
static LPDIRECTINPUTlpdi;// DirectInput interface 
static LPDIRECTINPUTDEVICE      lpdiKeyboard;           // keyboard device interface 
static BOOLfKeybdAcquired;// has the keyboard been acquired? 
 
extern DWORDgdwKeys;// gameplay keys 
 
/* 
* 
* InitInput 
* 
* Initialize DirectInput objects & devices 
* 
*/ 
BOOL InitInput(void) 
{ 
GUIDguid = GUID_SysKeyboard; 
   HRESULT  hRes; 
 
// try to create di object (DIRECTINPUT_VERSION == DX5) 
if(DirectInputCreate(ghinst, DIRECTINPUT_VERSION, &lpdi, NULL) != DI_OK) 
{ 
      // creation failed, try DX3 compatibility 
      if(DirectInputCreate(ghinst, 0x0300, &lpdi, NULL) != DI_OK) 
      { 
         ShowError(IDS_DINPUT_ERROR_DIC); 
         return FALSE; 
      } 
} 
 
 
// try to create keyboard device 
        if(lpdi->lpVtbl->CreateDevice(lpdi, &guid, &lpdiKeyboard, NULL) !=DI_OK) 
{ 
ShowError(IDS_DINPUT_ERROR_CD); 
return FALSE; 
} 
 
        // Tell DirectInput that we want to receive data in keyboard format 
        if (lpdiKeyboard->lpVtbl->SetDataFormat(lpdiKeyboard, &c_dfDIKeyboard) != DI_OK) 
        { 
                ShowError(IDS_DINPUT_ERROR_DF); 
                return FALSE; 
        } 
 
        // set cooperative level 
        if(lpdiKeyboard->lpVtbl->SetCooperativeLevel(lpdiKeyboard, ghWndMain, 
                         DISCL_NONEXCLUSIVE | DISCL_FOREGROUND) != DI_OK) 
{ 
ShowError(IDS_DINPUT_ERROR_SP); 
return FALSE; 
        } 
 
// try to acquire the keyboard 
   hRes = lpdiKeyboard->lpVtbl->Acquire(lpdiKeyboard); 
   if(SUCCEEDED(hRes)) 
   { 
      // keyboard was acquired 
      fKeybdAcquired = TRUE; 
} 
   else 
   { 
      // keyboard was NOT acquired 
      fKeybdAcquired = FALSE; 
   } 
 
// if we get here, all objects were created successfully 
return TRUE; 
 
} 
 
 
/* 
* 
* DI_ReadKeys 
* 
* Use DirectInput to read game-play keys 
* 
*/ 
void DI_ReadKeys(void) 
{ 
BYTE rgbKeybd[256]; 
   HRESULT hRes; 
 
   hRes = lpdiKeyboard->lpVtbl->GetDeviceState(lpdiKeyboard, sizeof(rgbKeybd), rgbKeybd); 
   if(hRes != DI_OK) 
{ 
      if(hRes == DIERR_INPUTLOST) 
      { 
         // we lost control of the keyboard, reacquire 
         fKeybdAcquired = FALSE; 
         if(SUCCEEDED(lpdiKeyboard->lpVtbl->Acquire(lpdiKeyboard))) 
         { 
            fKeybdAcquired = TRUE; 
         } 
      } 
 
      // failed to read the keyboard, just return 
return; 
} 
 
// reset key states 
gdwKeys = gdwKeys ^ gdwKeys; 
 
// check & update key states 
if(rgbKeybd[DIK_NUMPAD5] & 0x80) 
gdwKeys |= KEY_STOP; 
 
if((rgbKeybd[DIK_NUMPAD2] & 0x80) || (rgbKeybd[DIK_DOWN] & 0x80)) 
gdwKeys |= KEY_DOWN; 
 
if((rgbKeybd[DIK_NUMPAD4] & 0x80) || (rgbKeybd[DIK_LEFT] & 0x80)) 
gdwKeys |= KEY_LEFT; 
 
if((rgbKeybd[DIK_NUMPAD6] & 0x80) || (rgbKeybd[DIK_RIGHT] & 0x80)) 
gdwKeys |= KEY_RIGHT; 
 
if((rgbKeybd[DIK_NUMPAD8] & 0x80) || (rgbKeybd[DIK_UP] & 0x80)) 
gdwKeys |= KEY_UP; 
 
if(rgbKeybd[DIK_SPACE] & 0x80) 
gdwKeys |= KEY_FIRE; 
 
} 
 
/* 
* 
* CleanupInput 
* 
* Cleans up DirectInput objects 
* 
*/ 
void CleanupInput(void) 
{ 
if(fKeybdAcquired) 
{ 
lpdiKeyboard->lpVtbl->Unacquire(lpdiKeyboard); 
fKeybdAcquired = FALSE; 
} 
 
if(lpdiKeyboard != NULL) 
lpdiKeyboard->lpVtbl->Release(lpdiKeyboard); 
 
if(lpdi!= NULL) 
lpdi->lpVtbl->Release(lpdi); 
 
} 
 
 
/* 
* 
* ReacquireInputDevices 
* 
* Reacquires DirectInput devices as needed 
* 
*/ 
BOOL ReacquireInputDevices(void) 
{ 
// try to acquire the keyboard 
        if(lpdiKeyboard != NULL) 
        { 
                lpdiKeyboard->lpVtbl->Acquire(lpdiKeyboard); 
     } 
        else 
        { 
                // keyboard device has not been created. 
                fKeybdAcquired = FALSE; 
                return FALSE; 
        } 
 
        // if we get here, we are acquired again 
        fKeybdAcquired = TRUE; 
        return TRUE; 
}