游戏引擎

开发平台：
Visual C++

Audio.cpp：源码内容
							// Audio.cpp: implementation of the CAudio class.
//
//////////////////////////////////////////////////////////////////////
#include "stdafx.h"
#include "Audio.h"
//////////////////////////////////////////////////////////////////////
// Construction/Destruction
//////////////////////////////////////////////////////////////////////
void CSound::
	Set3DPos(float x, float y, float z)
	{	ds3DBuffer->SetPosition(x, y, -z, DS3D_IMMEDIATE);	}
//------------------------------------------------------------------//
//- void CSound::Set3DDistances(float, float) -----------------------//
//------------------------------------------------------------------//
//- Sets the max, and minimum distance for a CSound to be heard.	   -//
//------------------------------------------------------------------//
void CSound::
	Set3DDistances(float minDistance, float maxDistance)
	{
	DS3DBUFFER dsBufferParams;
	dsBufferParams.flMinDistance= minDistance;	//Sets the minimum distance
	dsBufferParams.flMaxDistance= maxDistance;	//Sets the maximum distance
	//Now, set the parameters for our CSound's 3D buffer
	if(ds3DBuffer)
		ds3DBuffer->SetAllParameters(&dsBufferParams, DS3D_IMMEDIATE);
	}
//------------------------------------------------------------------//
//- void CSound::Shutdown(void) -------------------------------------//
//------------------------------------------------------------------//
//- Shutdown the CSound, I originally had this in the destructor,   -//
//- but it was acting screwy... so I now it has it's own function. -//
//------------------------------------------------------------------//
void CSound::
	Shutdown(void)
	{
	if(dmSegment!=NULL)
		{
		dmSegment->Release();
		dmSegment= NULL;
		}
	if(ds3DBuffer!=NULL)
		{
		ds3DBuffer->Release(); 
		ds3DBuffer= NULL;
		}
	}
//------------------------------------------------------------------//
//- bool CAudio::Init(void) ----------------------------------//
//------------------------------------------------------------------//
//- Initiates DirectAudio.  This function must be called by the    -//
//- programmer, though the shutdown function is automatically	   -//
//- called by the destructor (as, not shutting down DAudio		   -//
//- correctly can have some bad consequences).					   -//
//------------------------------------------------------------------//
bool CAudio::
	Init(HWND hwnd,unsigned int MaxNumber)
	{
	HRESULT hr;
	WCHAR wcharStr[MAX_PATH];
	char pathStr[MAX_PATH];
	CoInitialize(NULL);
	//Create the loader object, load it... and load it good.
	hr= CoCreateInstance(CLSID_DirectMusicLoader, NULL, CLSCTX_INPROC,
						IID_IDirectMusicLoader8, (void**)&dmLoader);
	if(FAILED(hr))
		{
		MessageBox(hwnd, "Unable to create main DirectAudio file loader", "ERROR", MB_OK);
		return false;
		}
	//Create the performance object for that.... performance stuff. 
	hr= CoCreateInstance(CLSID_DirectMusicPerformance, NULL, CLSCTX_INPROC,
						 IID_IDirectMusicPerformance8, (void**)&dmPerformance);
	if(FAILED(hr))
		{
		MessageBox(hwnd, "Unable to create main DirectAudio performance object", "ERROR", MB_OK);
		Shutdown();
		return false;
		}
	//Initialize the performance with the standard audio path information
	dmPerformance->InitAudio(NULL, NULL, hwnd, DMUS_APATH_DYNAMIC_3D , 64,
							 DMUS_AUDIOF_ALL, NULL);
     //Create a simple 3D audiopath
	 hr= dmPerformance->CreateStandardAudioPath(DMUS_APATH_DYNAMIC_3D,
												64, TRUE, &dm3DAudioPath);
     if(FAILED(hr))
		{
		MessageBox(hwnd, "Unable to create the DirectAudio audio path", "ERROR", MB_OK);
		Shutdown();
		return false;
		}
     //Retrieve the listener information from our audiopath
	 hr= dm3DAudioPath->GetObjectInPath(0, DMUS_PATH_PRIMARY_BUFFER, 0, GUID_NULL, 0, 
											IID_IDirectSound3DListener8,
											(void**)&ds3DListener);
     if(FAILED(hr))
		{
		MessageBox(hwnd, "Unable to recieve listener from audio path", "ERROR", MB_OK);
		Shutdown();
		return false;
		}
	//Get the listener information
	dsListenerParams.dwSize= sizeof(DS3DLISTENER);
	ds3DListener->GetAllParameters(&dsListenerParams);
	//Set our default position of listener (since the listener shouldn't be moving all too much
	dsListenerParams.vPosition.x= 0.0f;
	dsListenerParams.vPosition.y= 0.0f;
	dsListenerParams.vPosition.z= 0.0f;
	ds3DListener->SetAllParameters(&dsListenerParams, DS3D_IMMEDIATE);
	//Retrieve the current directory
	GetCurrentDirectory(MAX_PATH, pathStr);
	//Convert the file name to a unicode string... as thats what COM needs
	MultiByteToWideChar(CP_ACP, 0, pathStr, -1, wcharStr, MAX_PATH);
	//Set the search directory
	dmLoader->SetSearchDirectory(GUID_DirectMusicAllTypes, wcharStr, FALSE);
	m_MaxNum=MaxNumber;
	pSound=new CSound[m_MaxNum];
	return true;
	}
//------------------------------------------------------------------//
//- void CAudio::DAudioShutdown(void) ------------------------//
//------------------------------------------------------------------//
//- Shuts down DirectAudio.  This function is called automatically -//
//- by the CAudio destructor, hence the reason why this	   -//
//- function is private.										   -//
//------------------------------------------------------------------//
void CAudio::Shutdown(void)
{
    for(unsigned int i=0;i < m_MaxNum;i++)
	{
		pSound[i].Shutdown();
	}
    delete [] pSound;
	//Shut down the direct CSound listener(player) information
	if(ds3DListener!=NULL)
		ds3DListener->Release();
	//Shut down the direct music performance information
	if(dmPerformance!=NULL)
		{
		dmPerformance->Stop(NULL, NULL, 0, 0);
		dmPerformance->CloseDown();
		dmPerformance->Release();
		}
	//Shut down the direct music audiopath
	if(dm3DAudioPath!=NULL)
		dm3DAudioPath->Release();
	//Shut down the direct music loader
  	if(dmLoader!=NULL)
    	dmLoader->Release();
	//Uninitialize COM (*MUST* be done, or you're asking for trouble)
	CoUninitialize();
	}
//------------------------------------------------------------------//
//- bool CAudio::Create(CSound*, char*, bool) -----------------//
//------------------------------------------------------------------//
//- Use the audio manager to create an individual CSound effect from-//
//- a file.														   -//
//------------------------------------------------------------------//
bool CAudio::
	Create(unsigned int NumOfSound, char* filename, bool is3DSound)
	{
	if(NumOfSound>(m_MaxNum-1))return false;
	DS3DBUFFER dsBufferParams; 
	HRESULT hr;
	WCHAR wcharStr[MAX_PATH];
	//Convert the file name to the string that DirectAudio needs
	MultiByteToWideChar(CP_ACP, 0, filename, -1, wcharStr, MAX_PATH);
	//Load the audio segment from a file
	hr= dmLoader->LoadObjectFromFile(CLSID_DirectMusicSegment,
									 IID_IDirectMusicSegment8,
									 wcharStr,
									 (void**)&pSound[NumOfSound].dmSegment);
	if(FAILED(hr))
		{
		return false;
		}
	//Do code specific for 3D CSounds
	if(is3DSound)
		{
		//Get the 3D buffer, and audio path
		hr= dm3DAudioPath->GetObjectInPath(DMUS_PCHANNEL_ALL, DMUS_PATH_BUFFER, 0, 
										   GUID_NULL, 0, IID_IDirectSound3DBuffer,
										   (void**)&pSound[NumOfSound].ds3DBuffer);
		if(FAILED(hr))
			{
			
			return false;
			}
		//Get the 3D buffer paramters
		dsBufferParams.dwSize= sizeof(DS3DBUFFER);
		pSound[NumOfSound].ds3DBuffer->GetAllParameters(&dsBufferParams);
		//Set some new parameters
		dsBufferParams.dwMode= DS3DMODE_HEADRELATIVE;    // relative to the listener
		pSound[NumOfSound].ds3DBuffer->SetAllParameters(&dsBufferParams, DS3D_IMMEDIATE);
		//Set the 3D CSound flag to true
		pSound[NumOfSound].is3DSound = true;
		}
	//Do code specific to non-3D CSounds (background music)
	else
		{
		//Set the 3D buffer to null since we don't need it
		pSound[NumOfSound].ds3DBuffer= NULL;
		//Set the 3D CSound flag to false, since we don't need it either
		pSound[NumOfSound].is3DSound= false;
		}
	return true;
	}
//------------------------------------------------------------------//
//- void CAudio::Play(CSound*, DWORD) -------------------------//
//------------------------------------------------------------------//
//- Play the CSound, and repeat it numRepeats amount of times.	   -//
//------------------------------------------------------------------//
void CAudio::
	Play(unsigned int NumOfSound, DWORD numRepeats)
	{
	if(NumOfSound>(m_MaxNum-1))return ;
	//Set the number of repeats that we want for the specific CSound
	pSound[NumOfSound].dmSegment->SetRepeats(numRepeats);
	if(pSound[NumOfSound].is3DSound)
		{
		pSound[NumOfSound].dmSegment->Download(dmPerformance);
		//Play the segment using the 3D audio path
		dmPerformance->PlaySegmentEx(pSound[NumOfSound].dmSegment, NULL, NULL, 
									 DMUS_SEGF_ALIGN , 0,
									 NULL, NULL, dm3DAudioPath);
		}
	else
		{
		//Download the segment's performance object
		pSound[NumOfSound].dmSegment->Download(dmPerformance);
		//Play the non-3D CSound segment
		dmPerformance->PlaySegmentEx(pSound[NumOfSound].dmSegment, NULL, NULL, 
									 DMUS_SEGF_DEFAULT, 0,
									 NULL, NULL, NULL);
		}
	}
//------------------------------------------------------------------//
//- void CAudio::Stop(CSound*) --------------------------------//
//------------------------------------------------------------------//
//- Stop playing the specified CSound.							   -//
//------------------------------------------------------------------//
void CAudio::
	Stop(unsigned int NumOfSound)
	{
	if(NumOfSound>(m_MaxNum-1))  return  ;
	dmPerformance->StopEx(pSound[NumOfSound].dmSegment, 0, 0);	
}
//------------------------------------------------------------------//
//- void CAudio::SetListenerPos(float, float, float) ---------//
//------------------------------------------------------------------//
//- Set the listener's (player's) position in 3D space.			   -//
//------------------------------------------------------------------//
void CAudio::
	SetListenerPos(float x, float y, float z)
	{
	//Get the listener parameters
	dsListenerParams.dwSize= sizeof(DS3DLISTENER);
	ds3DListener->GetAllParameters(&dsListenerParams);
	//Set the listener's position in 3D space
	dsListenerParams.vPosition.x=  x;
	dsListenerParams.vPosition.y=  y;
	dsListenerParams.vPosition.z= -z;
	//Set all of the new parameters
	ds3DListener->SetAllParameters(&dsListenerParams, DS3D_IMMEDIATE);
	}
//------------------------------------------------------------------//
//- void CAudio::SetListenerRolloff(float) -------------------//
//------------------------------------------------------------------//
//- Set the listener's CSound volume rolloff with distance.		   -//
//------------------------------------------------------------------//
void CAudio::
	SetListenerRolloff(float rolloff)
	{
	if(ds3DListener)
		ds3DListener->SetRolloffFactor(rolloff, DS3D_IMMEDIATE);
	}
//------------------------------------------------------------------//
//- void CAudio::SetListenerOrientation(float, float, float, float, float, float) -//
//------------------------------------------------------------------//
//- Set the listener's orientation (you may need to implement a    -//
//- camera class to use this function correctly).				   -//
//------------------------------------------------------------------//
void CAudio::
	SetListenerOrientation(float forwardX, float forwardY, float forwardZ,
						   float topX, float topY, float topZ)
	{
	ds3DListener->SetOrientation(forwardX, forwardY, -forwardZ, 
								 topX, topY, topZ, DS3D_IMMEDIATE);
	}

						