2.4-Crystalpoint/OpenAL.cpp

#include "OpenAL.h"
#include <cstdlib>
#include <iostream>
#include <windows.h>
#include <al.h>
#include <alc.h>

OpenAL::OpenAL()
{
	Init();

}

int OpenAL::EndWithError(char* msg)
{
	//Display error message in console
	int error = 0;
	std::cout << msg << "\n";
	system("PAUSE");
	return error;
}

int OpenAL::Init()
{
	//Loading of the WAVE file
	FILE *fp = NULL;                                                            //Create FILE pointer for the WAVE file
	fp = fopen("WAVE/Sound.wav", "rb");                                            //Open the WAVE file
	if (!fp) return EndWithError("Failed to open file");                        //Could not open file

																				//Variables to store info about the WAVE file (all of them is not needed for OpenAL)
	char type[4];
	DWORD size, chunkSize;
	short formatType, channels;
	DWORD sampleRate, avgBytesPerSec;
	short bytesPerSample, bitsPerSample;
	DWORD dataSize;

	//Check that the WAVE file is OK
	fread(type, sizeof(char), 4, fp);                                              //Reads the first bytes in the file
	if (type[0] != 'R' || type[1] != 'I' || type[2] != 'F' || type[3] != 'F')            //Should be "RIFF"
		return EndWithError("No RIFF");                                            //Not RIFF

	fread(&size, sizeof(DWORD), 1, fp);                                           //Continue to read the file
	fread(type, sizeof(char), 4, fp);                                             //Continue to read the file
	if (type[0] != 'W' || type[1] != 'A' || type[2] != 'V' || type[3] != 'E')           //This part should be "WAVE"
		return EndWithError("not WAVE");                                            //Not WAVE

	fread(type, sizeof(char), 4, fp);                                              //Continue to read the file
	if (type[0] != 'f' || type[1] != 'm' || type[2] != 't' || type[3] != ' ')           //This part should be "fmt "
		return EndWithError("not fmt ");                                            //Not fmt 

																					//Now we know that the file is a acceptable WAVE file
																					//Info about the WAVE data is now read and stored
	fread(&chunkSize, sizeof(DWORD), 1, fp);
	fread(&formatType, sizeof(short), 1, fp);
	fread(&channels, sizeof(short), 1, fp);
	fread(&sampleRate, sizeof(DWORD), 1, fp);
	fread(&avgBytesPerSec, sizeof(DWORD), 1, fp);
	fread(&bytesPerSample, sizeof(short), 1, fp);
	fread(&bitsPerSample, sizeof(short), 1, fp);

	fread(type, sizeof(char), 4, fp);
	if (type[0] != 'd' || type[1] != 'a' || type[2] != 't' || type[3] != 'a')           //This part should be "data"
		return EndWithError("Missing DATA");                                        //not data

	fread(&dataSize, sizeof(DWORD), 1, fp);                                        //The size of the sound data is read

																				   //Display the info about the WAVE file
	std::cout << "Chunk Size: " << chunkSize << "\n";
	std::cout << "Format Type: " << formatType << "\n";
	std::cout << "Channels: " << channels << "\n";
	std::cout << "Sample Rate: " << sampleRate << "\n";
	std::cout << "Average Bytes Per Second: " << avgBytesPerSec << "\n";
	std::cout << "Bytes Per Sample: " << bytesPerSample << "\n";
	std::cout << "Bits Per Sample: " << bitsPerSample << "\n";
	std::cout << "Data Size: " << dataSize << "\n";

	unsigned char* buf = new unsigned char[dataSize];                            //Allocate memory for the sound data
	std::cout << fread(buf, sizeof(BYTE), dataSize, fp) << " bytes loaded\n";           //Read the sound data and display the 
																				   //number of bytes loaded.
																				   //Should be the same as the Data Size if OK


																				   //Now OpenAL needs to be initialized 
	ALCdevice *device;                                                          //Create an OpenAL Device
	ALCcontext *context;                                                        //And an OpenAL Context
	device = alcOpenDevice(NULL);                                               //Open the device
	if (!device) return EndWithError("no sound device");                         //Error during device oening
	context = alcCreateContext(device, NULL);                                   //Give the device a context
	alcMakeContextCurrent(context);                                             //Make the context the current
	if (!context) return EndWithError("no sound context");                       //Error during context handeling

	ALuint source;                                                              //Is the name of source (where the sound come from)
	ALuint buffer;                                                           //Stores the sound data
	ALuint frequency = sampleRate;;                                               //The Sample Rate of the WAVE file
	ALenum format = 0;                                                            //The audio format (bits per sample, number of channels)

	alGenBuffers(1, &buffer);                                                    //Generate one OpenAL Buffer and link to "buffer"
	alGenSources(1, &source);                                                   //Generate one OpenAL Source and link to "source"
	if (alGetError() != AL_NO_ERROR) return EndWithError("Error GenSource");     //Error during buffer/source generation

																				 //Figure out the format of the WAVE file
	if (bitsPerSample == 8)
	{
		if (channels == 1)
			format = AL_FORMAT_MONO8;
		else if (channels == 2)
			format = AL_FORMAT_STEREO8;
	}
	else if (bitsPerSample == 16)
	{
		if (channels == 1)
			format = AL_FORMAT_MONO16;
		else if (channels == 2)
			format = AL_FORMAT_STEREO16;
	}
	if (!format) return EndWithError("Wrong BitPerSample");                      //Not valid format

	alBufferData(buffer, format, buf, dataSize, frequency);                    //Store the sound data in the OpenAL Buffer
	if (alGetError() != AL_NO_ERROR)
		return EndWithError("Error loading ALBuffer");                              //Error during buffer loading

																					//Sound setting variables
	ALfloat SourcePos[] = { 0.0, 0.0, 0.0 };                                    //Position of the source sound
	ALfloat SourceVel[] = { 0.0, 0.0, 0.0 };                                    //Velocity of the source sound
	ALfloat ListenerPos[] = { 0.0, 0.0, 0.0 };                                  //Position of the listener
	ALfloat ListenerVel[] = { 0.0, 0.0, 0.0 };                                  //Velocity of the listener
	ALfloat ListenerOri[] = { 0.0, 0.0, -1.0,  0.0, 1.0, 0.0 };                 //Orientation of the listener
																				//First direction vector, then vector pointing up) 
																				//Listener                                                                               
	alListenerfv(AL_POSITION, ListenerPos);                                  //Set position of the listener
	alListenerfv(AL_VELOCITY, ListenerVel);                                  //Set velocity of the listener
	alListenerfv(AL_ORIENTATION, ListenerOri);                                  //Set orientation of the listener

																				//Source
	alSourcei(source, AL_BUFFER, buffer);                                 //Link the buffer to the source
	alSourcef(source, AL_PITCH, 1.0f);                                 //Set the pitch of the source
	alSourcef(source, AL_GAIN, 1.0f);                                 //Set the gain of the source
	alSourcefv(source, AL_POSITION, SourcePos);                                 //Set the position of the source
	alSourcefv(source, AL_VELOCITY, SourceVel);                                 //Set the velocity of the source
	alSourcei(source, AL_LOOPING, AL_FALSE);                                 //Set if source is looping sound

																			 //PLAY 
	alSourcePlay(source);                                                       //Play the sound buffer linked to the source
	if (alGetError() != AL_NO_ERROR) return EndWithError("Error playing sound"); //Error when playing sound
	//system("PAUSE");                                                            //Pause to let the sound play

																				//Clean-up
	fclose(fp);                                                                 //Close the WAVE file
	delete[] buf;                                                               //Delete the sound data buffer
	alDeleteSources(1, &source);                                                //Delete the OpenAL Source
	alDeleteBuffers(1, &buffer);                                                 //Delete the OpenAL Buffer
	alcMakeContextCurrent(NULL);                                                //Make no context current
	alcDestroyContext(context);                                                 //Destroy the OpenAL Context
	alcCloseDevice(device);                                                     //Close the OpenAL Device

	return EXIT_SUCCESS;
}


OpenAL::~OpenAL()
{
}