C++ : AL/altypes. h 没有那个文件或目录

Question

我正在尝试开始使用 OpenAL。

我正在尝试编译我从 here 获得的这个程序使用:

g++ main.cpp -lOpenAL

此时出现错误"AL/altypes.h"No such file or directory.。有谁知道我该如何解决这个问题？我已经安装了 libopenal-dev。 (我认为我在 Ubuntu 13.04 上？)

#include <iostream>
#include <cstdlib>
#include <AL/altypes.h>
#include <AL/al.h>
#include <AL/alu.h>
#include <AL/alut.h>


#define NUM_BUFFERS 1
#define NUM_SOURCES 1
#define NUM_ENVIRONMENTS 1

ALfloat listenerPos[] = {0.0, 0.0, 4.0};
ALfloat listenerVel[] = {0.0, 0.0, 0.0};
ALfloat listenerOri[] = {0.0, 0.0, 1.0, 0.0, 1.0, 0.0};

ALfloat source0Pos[] = {0.0, 0.0, 0.0};
ALfloat source0Vel[] = {0.0, 0.0, 0.0};

ALuint buffer[NUM_BUFFERS];
ALuint source[NUM_SOURCES];
ALuint environment[NUM_ENVIRONMENTS];

ALsizei size, freq;
ALenum format;
ALvoid* data;

void init(void)
{
    alListenerfv(AL_POSITION,listenerPos);
    alListenerfv(AL_VELOCITY,listenerVel);
    alListenerfv(AL_ORIENTATION,listenerOri);

    alGetError(); // clear any error messages

    // Generate buffers, or else no sound will happen!
    alGenBuffers(NUM_BUFFERS, buffer);

    if(alGetError() != AL_NO_ERROR) 
    {
        std::cout << "- Error creating buffers !!" << std::endl;
        exit(1);
    }
    else
    {
        std::cout << "init() - No errors yet." << std::endl;
    }

    alutLoadWAVFile((Albyte *) "c.wav", &format, &data, size,&freq, &al_bool);
    alBufferData(buffer[0],format,data,size,freq);
    alutUnloadWAV(format,data,size,freq);

    alGetError(); /* clear error */
    alGenSources(NUM_SOURCES, source);

    if(alGetError() != AL_NO_ERROR) 
    {
        std::cout << "- Error creating sources !!" << std::endl;
        exit(2);
    }
    else
    {
        std::cout << "init - no errors after alGenSources" << std::endl;
    }

    alSourcef(source[0], AL_PITCH, 1.0f);
    alSourcef(source[0], AL_GAIN, 1.0f);
    alSourcefv(source[0], AL_POSITION, source0Pos);
    alSourcefv(source[0], AL_VELOCITY, source0Vel);
    alSourcei(source[0], AL_BUFFER,buffer[0]);
    alSourcei(source[0], AL_LOOPING, AL_TRUE);
}

int main()
{

    //initialise openAL
    alutInit(&argc, argv) ; 

    init();

    return 0;
}

顺便说一句，这个程序目前实际上不会做我想做的事。

我想声明一个 double/int 数组，用数据填充它并播放该数据。有谁知道我该怎么做？

Answer 1

有一个包含实用程序的包 libalut-dev，但是请查看用于音频文件 I/O 的 libsndfile。推出您自己的 WAV/PCM 解析器始终是一个 chalice ，它可以教给您很多东西，而且并不难。 WRT 你在一边......以下开放代码将数据合成到一个开放缓冲区中，然后将其呈现为音频。下面的另一页代码将为您提供一个流媒体音频播放器，这很方便。编译它使用

gcc -o gen_tone_08  gen_tone_08.c -lopenal -lm

告诉我们你过得怎么样

#include <stdio.h>
#include <stdlib.h>    // gives malloc
#include <math.h>


#ifdef __APPLE__
#include <OpenAL/al.h>
#include <OpenAL/alc.h>
#elif __linux
#include <AL/al.h>
#include <AL/alc.h>
#endif

ALCdevice  * openal_output_device;
ALCcontext * openal_output_context;

ALuint internal_buffer;
ALuint streaming_source[1];

int al_check_error(const char * given_label) {

    ALenum al_error;
    al_error = alGetError();

    if(AL_NO_ERROR != al_error) {

        printf("ERROR - %s  (%s)\n", alGetString(al_error), given_label);
        return al_error;
    }
    return 0;
}

void MM_init_al() {

    const char * defname = alcGetString(NULL, ALC_DEFAULT_DEVICE_SPECIFIER);

    openal_output_device  = alcOpenDevice(defname);
    openal_output_context = alcCreateContext(openal_output_device, NULL);
    alcMakeContextCurrent(openal_output_context);

    // setup buffer and source

    alGenBuffers(1, & internal_buffer);
    al_check_error("failed call to alGenBuffers");
}

void MM_exit_al() {

    ALenum errorCode = 0;

    // Stop the sources
    alSourceStopv(1, & streaming_source[0]);        //      streaming_source
    int ii;
    for (ii = 0; ii < 1; ++ii) {
        alSourcei(streaming_source[ii], AL_BUFFER, 0);
    }
    // Clean-up
    alDeleteSources(1, &streaming_source[0]);
    alDeleteBuffers(16, &streaming_source[0]);
    errorCode = alGetError();
    alcMakeContextCurrent(NULL);
    errorCode = alGetError();
    alcDestroyContext(openal_output_context);
    alcCloseDevice(openal_output_device);
}

void MM_render_one_buffer() {

    /* Fill buffer with Sine-Wave */
    // float freq = 440.f;
    float freq = 100.f;
    float incr_freq = 0.1f;

    int seconds = 4;
    // unsigned sample_rate = 22050;
    unsigned sample_rate = 44100;
    double my_pi = 3.14159;
    size_t buf_size = seconds * sample_rate;

    short * samples = malloc(sizeof(short) * buf_size);

   printf("\nhere is freq %f\n", freq);
    int i=0;
    for(; i<buf_size; ++i) {
        samples[i] = 32760 * sin( (2.f * my_pi * freq)/sample_rate * i );

        freq += incr_freq;
        // incr_freq += incr_freq;
        // freq *= factor_freq;

        if (100.0 > freq || freq > 5000.0) {

            incr_freq *= -1.0f;
        }
    }

    /* upload buffer to OpenAL */
    alBufferData( internal_buffer, AL_FORMAT_MONO16, samples, buf_size, sample_rate);
    al_check_error("populating alBufferData");

    free(samples);

    /* Set-up sound source and play buffer */
    // ALuint src = 0;
    // alGenSources(1, &src);
    // alSourcei(src, AL_BUFFER, internal_buffer);
    alGenSources(1, & streaming_source[0]);
    alSourcei(streaming_source[0], AL_BUFFER, internal_buffer);
    // alSourcePlay(src);
    alSourcePlay(streaming_source[0]);

    // ---------------------

    ALenum current_playing_state;
    alGetSourcei(streaming_source[0], AL_SOURCE_STATE, & current_playing_state);
    al_check_error("alGetSourcei AL_SOURCE_STATE");

    while (AL_PLAYING == current_playing_state) {

        printf("still playing ... so sleep\n");

        sleep(1);   // should use a thread sleep NOT sleep() for a more responsive finish

        alGetSourcei(streaming_source[0], AL_SOURCE_STATE, & current_playing_state);
        al_check_error("alGetSourcei AL_SOURCE_STATE");
    }

    printf("end of playing\n");

    /* Dealloc OpenAL */
    MM_exit_al();

}   //  MM_render_one_buffer

int main() {

    MM_init_al();

    MM_render_one_buffer();
}