examples/altonegen.c

   1 /*
   2  * OpenAL Tone Generator Test
   3  *
   4  * Copyright (c) 2015 by Chris Robinson <chris.kcat@gmail.com>
   5  *
   6  * Permission is hereby granted, free of charge, to any person obtaining a copy
   7  * of this software and associated documentation files (the "Software"), to deal
   8  * in the Software without restriction, including without limitation the rights
   9  * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
  10  * copies of the Software, and to permit persons to whom the Software is
  11  * furnished to do so, subject to the following conditions:
  12  *
  13  * The above copyright notice and this permission notice shall be included in
  14  * all copies or substantial portions of the Software.
  15  *
  16  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
  17  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  18  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
  19  * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
  20  * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
  21  * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
  22  * THE SOFTWARE.
  23  */
  24
  25 /* This file contains a test for generating waveforms and plays them for a
  26  * given length of time. Intended to inspect the behavior of the mixer by
  27  * checking the output with a spectrum analyzer and oscilloscope.
  28  *
  29  * TODO: This would actually be nicer as a GUI app with buttons to start and
  30  * stop individual waveforms, include additional whitenoise and pinknoise
  31  * generators, and have the ability to hook up EFX filters and effects.
  32  */
  33
  34 #include <stdio.h>
  35 #include <stdlib.h>
  36 #include <string.h>
  37 #include <assert.h>
  38 #include <limits.h>
  39 #include <math.h>
  40
  41 #include "AL/al.h"
  42 #include "AL/alc.h"
  43 #include "AL/alext.h"
  44
  45 #include "common/alhelpers.h"
  46
  47 #ifndef M_PI
  48 #define M_PI    (3.14159265358979323846)
  49 #endif
  50
  51 enum WaveType {
  52     WT_Sine,
  53     WT_Square,
  54     WT_Sawtooth,
  55     WT_Triangle,
  56     WT_Impulse,
  57     WT_WhiteNoise,
  58 };
  59
  60 static const char *GetWaveTypeName(enum WaveType type)
  61 {
  62     switch(type)
  63     {
  64         case WT_Sine: return "sine";
  65         case WT_Square: return "square";
  66         case WT_Sawtooth: return "sawtooth";
  67         case WT_Triangle: return "triangle";
  68         case WT_Impulse: return "impulse";
  69         case WT_WhiteNoise: return "noise";
  70     }
  71     return "(unknown)";
  72 }
  73
  74 static inline ALuint dither_rng(ALuint *seed)
  75 {
  76     *seed = (*seed * 96314165) + 907633515;
  77     return *seed;
  78 }
  79
  80 static void ApplySin(ALfloat *data, ALdouble g, ALuint srate, ALuint freq)
  81 {
  82     ALdouble smps_per_cycle = (ALdouble)srate / freq;
  83     ALuint i;
  84     for(i = 0;i < srate;i++)
  85     {
  86         ALdouble ival;
  87         data[i] += (ALfloat)(sin(modf(i/smps_per_cycle, &ival) * 2.0*M_PI) * g);
  88     }
  89 }
  90
  91 /* Generates waveforms using additive synthesis. Each waveform is constructed
  92  * by summing one or more sine waves, up to (and excluding) nyquist.
  93  */
  94 static ALuint CreateWave(enum WaveType type, ALuint freq, ALuint srate)
  95 {
  96     ALuint seed = 22222;
  97     ALuint data_size;
  98     ALfloat *data;
  99     ALuint buffer;
 100     ALenum err;
 101     ALuint i;
 102
 103     data_size = (ALuint)(srate * sizeof(ALfloat));
 104     data = calloc(1, data_size);
 105     switch(type)
 106     {
 107         case WT_Sine:
 108             ApplySin(data, 1.0, srate, freq);
 109             break;
 110         case WT_Square:
 111             for(i = 1;freq*i < srate/2;i+=2)
 112                 ApplySin(data, 4.0/M_PI * 1.0/i, srate, freq*i);
 113             break;
 114         case WT_Sawtooth:
 115             for(i = 1;freq*i < srate/2;i++)
 116                 ApplySin(data, 2.0/M_PI * ((i&1)*2 - 1.0) / i, srate, freq*i);
 117             break;
 118         case WT_Triangle:
 119             for(i = 1;freq*i < srate/2;i+=2)
 120                 ApplySin(data, 8.0/(M_PI*M_PI) * (1.0 - (i&2)) / (i*i), srate, freq*i);
 121             break;
 122         case WT_Impulse:
 123             /* NOTE: Impulse isn't handled using additive synthesis, and is
 124              * instead just a non-0 sample at a given rate. This can still be
 125              * useful to test (other than resampling, the ALSOFT_DEFAULT_REVERB
 126              * environment variable can prove useful here to test the reverb
 127              * response).
 128              */
 129             for(i = 0;i < srate;i++)
 130                 data[i] = (i%(srate/freq)) ? 0.0f : 1.0f;
 131             break;
 132         case WT_WhiteNoise:
 133             /* NOTE: WhiteNoise is just uniform set of uncorrelated values, and
 134              * is not influenced by the waveform frequency.
 135              */
 136             for(i = 0;i < srate;i++)
 137             {
 138                 ALuint rng0 = dither_rng(&seed);
 139                 ALuint rng1 = dither_rng(&seed);
 140                 data[i] = (ALfloat)(rng0*(1.0/UINT_MAX) - rng1*(1.0/UINT_MAX));
 141             }
 142             break;
 143     }
 144
 145     /* Buffer the audio data into a new buffer object. */
 146     buffer = 0;
 147     alGenBuffers(1, &buffer);
 148     alBufferData(buffer, AL_FORMAT_MONO_FLOAT32, data, (ALsizei)data_size, (ALsizei)srate);
 149     free(data);
 150
 151     /* Check if an error occured, and clean up if so. */
 152     err = alGetError();
 153     if(err != AL_NO_ERROR)
 154     {
 155         fprintf(stderr, "OpenAL Error: %s\n", alGetString(err));
 156         if(alIsBuffer(buffer))
 157             alDeleteBuffers(1, &buffer);
 158         return 0;
 159     }
 160
 161     return buffer;
 162 }
 163
 164
 165 int main(int argc, char *argv[])
 166 {
 167     enum WaveType wavetype = WT_Sine;
 168     const char *appname = argv[0];
 169     ALuint source, buffer;
 170     ALint last_pos, num_loops;
 171     ALint max_loops = 4;
 172     ALint srate = -1;
 173     ALint tone_freq = 1000;
 174     ALCint dev_rate;
 175     ALenum state;
 176     int i;
 177
 178     argv++; argc--;
 179     if(InitAL(&argv, &argc) != 0)
 180         return 1;
 181
 182     if(!alIsExtensionPresent("AL_EXT_FLOAT32"))
 183     {
 184         fprintf(stderr, "Required AL_EXT_FLOAT32 extension not supported on this device!\n");
 185         CloseAL();
 186         return 1;
 187     }
 188
 189     for(i = 0;i < argc;i++)
 190     {
 191         if(strcmp(argv[i], "-h") == 0 || strcmp(argv[i], "--help") == 0)
 192         {
 193             fprintf(stderr, "OpenAL Tone Generator\n"
 194 "\n"
 195 "Usage: %s [-device <name>] <options>\n"
 196 "\n"
 197 "Available options:\n"
 198 "  --help/-h                 This help text\n"
 199 "  -t <seconds>              Time to play a tone (default 5 seconds)\n"
 200 "  --waveform/-w <type>      Waveform type: sine (default), square, sawtooth,\n"
 201 "                                triangle, impulse, noise\n"
 202 "  --freq/-f <hz>            Tone frequency (default 1000 hz)\n"
 203 "  --srate/-s <sample rate>  Sampling rate (default output rate)\n",
 204                 appname
 205             );
 206             CloseAL();
 207             return 1;
 208         }
 209         else if(i+1 < argc && strcmp(argv[i], "-t") == 0)
 210         {
 211             i++;
 212             max_loops = atoi(argv[i]) - 1;
 213         }
 214         else if(i+1 < argc && (strcmp(argv[i], "--waveform") == 0 || strcmp(argv[i], "-w") == 0))
 215         {
 216             i++;
 217             if(strcmp(argv[i], "sine") == 0)
 218                 wavetype = WT_Sine;
 219             else if(strcmp(argv[i], "square") == 0)
 220                 wavetype = WT_Square;
 221             else if(strcmp(argv[i], "sawtooth") == 0)
 222                 wavetype = WT_Sawtooth;
 223             else if(strcmp(argv[i], "triangle") == 0)
 224                 wavetype = WT_Triangle;
 225             else if(strcmp(argv[i], "impulse") == 0)
 226                 wavetype = WT_Impulse;
 227             else if(strcmp(argv[i], "noise") == 0)
 228                 wavetype = WT_WhiteNoise;
 229             else
 230                 fprintf(stderr, "Unhandled waveform: %s\n", argv[i]);
 231         }
 232         else if(i+1 < argc && (strcmp(argv[i], "--freq") == 0 || strcmp(argv[i], "-f") == 0))
 233         {
 234             i++;
 235             tone_freq = atoi(argv[i]);
 236             if(tone_freq < 1)
 237             {
 238                 fprintf(stderr, "Invalid tone frequency: %s (min: 1hz)\n", argv[i]);
 239                 tone_freq = 1;
 240             }
 241         }
 242         else if(i+1 < argc && (strcmp(argv[i], "--srate") == 0 || strcmp(argv[i], "-s") == 0))
 243         {
 244             i++;
 245             srate = atoi(argv[i]);
 246             if(srate < 40)
 247             {
 248                 fprintf(stderr, "Invalid sample rate: %s (min: 40hz)\n", argv[i]);
 249                 srate = 40;
 250             }
 251         }
 252     }
 253
 254     {
 255         ALCdevice *device = alcGetContextsDevice(alcGetCurrentContext());
 256         alcGetIntegerv(device, ALC_FREQUENCY, 1, &dev_rate);
 257         assert(alcGetError(device)==ALC_NO_ERROR && "Failed to get device sample rate");
 258     }
 259     if(srate < 0)
 260         srate = dev_rate;
 261
 262     /* Load the sound into a buffer. */
 263     buffer = CreateWave(wavetype, (ALuint)tone_freq, (ALuint)srate);
 264     if(!buffer)
 265     {
 266         CloseAL();
 267         return 1;
 268     }
 269
 270     printf("Playing %dhz %s-wave tone with %dhz sample rate and %dhz output, for %d second%s...\n",
 271            tone_freq, GetWaveTypeName(wavetype), srate, dev_rate, max_loops+1, max_loops?"s":"");
 272     fflush(stdout);
 273
 274     /* Create the source to play the sound with. */
 275     source = 0;
 276     alGenSources(1, &source);
 277     alSourcei(source, AL_BUFFER, (ALint)buffer);
 278     assert(alGetError()==AL_NO_ERROR && "Failed to setup sound source");
 279
 280     /* Play the sound for a while. */
 281     num_loops = 0;
 282     last_pos = 0;
 283     alSourcei(source, AL_LOOPING, (max_loops > 0) ? AL_TRUE : AL_FALSE);
 284     alSourcePlay(source);
 285     do {
 286         ALint pos;
 287         al_nssleep(10000000);
 288         alGetSourcei(source, AL_SAMPLE_OFFSET, &pos);
 289         alGetSourcei(source, AL_SOURCE_STATE, &state);
 290         if(pos < last_pos && state == AL_PLAYING)
 291         {
 292             ++num_loops;
 293             if(num_loops >= max_loops)
 294                 alSourcei(source, AL_LOOPING, AL_FALSE);
 295             printf("%d...\n", max_loops - num_loops + 1);
 296             fflush(stdout);
 297         }
 298         last_pos = pos;
 299     } while(alGetError() == AL_NO_ERROR && state == AL_PLAYING);
 300
 301     /* All done. Delete resources, and close OpenAL. */
 302     alDeleteSources(1, &source);
 303     alDeleteBuffers(1, &buffer);
 304
 305     /* Close up OpenAL. */
 306     CloseAL();
 307
 308     return 0;
 309 }