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 #include "win_main_utf8.h"
  48
  49 #ifndef M_PI
  50 #define M_PI    (3.14159265358979323846)
  51 #endif
  52
  53 enum WaveType {
  54     WT_Sine,
  55     WT_Square,
  56     WT_Sawtooth,
  57     WT_Triangle,
  58     WT_Impulse,
  59     WT_WhiteNoise,
  60 };
  61
  62 static const char *GetWaveTypeName(enum WaveType type)
  63 {
  64     switch(type)
  65     {
  66         case WT_Sine: return "sine";
  67         case WT_Square: return "square";
  68         case WT_Sawtooth: return "sawtooth";
  69         case WT_Triangle: return "triangle";
  70         case WT_Impulse: return "impulse";
  71         case WT_WhiteNoise: return "noise";
  72     }
  73     return "(unknown)";
  74 }
  75
  76 static inline ALuint dither_rng(ALuint *seed)
  77 {
  78     *seed = (*seed * 96314165) + 907633515;
  79     return *seed;
  80 }
  81
  82 static void ApplySin(ALfloat *data, ALdouble g, ALuint srate, ALuint freq)
  83 {
  84     ALdouble smps_per_cycle = (ALdouble)srate / freq;
  85     ALuint i;
  86     for(i = 0;i < srate;i++)
  87     {
  88         ALdouble ival;
  89         data[i] += (ALfloat)(sin(modf(i/smps_per_cycle, &ival) * 2.0*M_PI) * g);
  90     }
  91 }
  92
  93 /* Generates waveforms using additive synthesis. Each waveform is constructed
  94  * by summing one or more sine waves, up to (and excluding) nyquist.
  95  */
  96 static ALuint CreateWave(enum WaveType type, ALuint freq, ALuint srate)
  97 {
  98     ALuint seed = 22222;
  99     ALuint data_size;
 100     ALfloat *data;
 101     ALuint buffer;
 102     ALenum err;
 103     ALuint i;
 104
 105     data_size = (ALuint)(srate * sizeof(ALfloat));
 106     data = calloc(1, data_size);
 107     switch(type)
 108     {
 109         case WT_Sine:
 110             ApplySin(data, 1.0, srate, freq);
 111             break;
 112         case WT_Square:
 113             for(i = 1;freq*i < srate/2;i+=2)
 114                 ApplySin(data, 4.0/M_PI * 1.0/i, srate, freq*i);
 115             break;
 116         case WT_Sawtooth:
 117             for(i = 1;freq*i < srate/2;i++)
 118                 ApplySin(data, 2.0/M_PI * ((i&1)*2 - 1.0) / i, srate, freq*i);
 119             break;
 120         case WT_Triangle:
 121             for(i = 1;freq*i < srate/2;i+=2)
 122                 ApplySin(data, 8.0/(M_PI*M_PI) * (1.0 - (i&2)) / (i*i), srate, freq*i);
 123             break;
 124         case WT_Impulse:
 125             /* NOTE: Impulse isn't handled using additive synthesis, and is
 126              * instead just a non-0 sample at a given rate. This can still be
 127              * useful to test (other than resampling, the ALSOFT_DEFAULT_REVERB
 128              * environment variable can prove useful here to test the reverb
 129              * response).
 130              */
 131             for(i = 0;i < srate;i++)
 132                 data[i] = (i%(srate/freq)) ? 0.0f : 1.0f;
 133             break;
 134         case WT_WhiteNoise:
 135             /* NOTE: WhiteNoise is just uniform set of uncorrelated values, and
 136              * is not influenced by the waveform frequency.
 137              */
 138             for(i = 0;i < srate;i++)
 139             {
 140                 ALuint rng0 = dither_rng(&seed);
 141                 ALuint rng1 = dither_rng(&seed);
 142                 data[i] = (ALfloat)(rng0*(1.0/UINT_MAX) - rng1*(1.0/UINT_MAX));
 143             }
 144             break;
 145     }
 146
 147     /* Buffer the audio data into a new buffer object. */
 148     buffer = 0;
 149     alGenBuffers(1, &buffer);
 150     alBufferData(buffer, AL_FORMAT_MONO_FLOAT32, data, (ALsizei)data_size, (ALsizei)srate);
 151     free(data);
 152
 153     /* Check if an error occured, and clean up if so. */
 154     err = alGetError();
 155     if(err != AL_NO_ERROR)
 156     {
 157         fprintf(stderr, "OpenAL Error: %s\n", alGetString(err));
 158         if(alIsBuffer(buffer))
 159             alDeleteBuffers(1, &buffer);
 160         return 0;
 161     }
 162
 163     return buffer;
 164 }
 165
 166
 167 int main(int argc, char *argv[])
 168 {
 169     enum WaveType wavetype = WT_Sine;
 170     const char *appname = argv[0];
 171     ALuint source, buffer;
 172     ALint last_pos, num_loops;
 173     ALint max_loops = 4;
 174     ALint srate = -1;
 175     ALint tone_freq = 1000;
 176     ALCint dev_rate;
 177     ALenum state;
 178     int i;
 179
 180     argv++; argc--;
 181     if(InitAL(&argv, &argc) != 0)
 182         return 1;
 183
 184     if(!alIsExtensionPresent("AL_EXT_FLOAT32"))
 185     {
 186         fprintf(stderr, "Required AL_EXT_FLOAT32 extension not supported on this device!\n");
 187         CloseAL();
 188         return 1;
 189     }
 190
 191     for(i = 0;i < argc;i++)
 192     {
 193         if(strcmp(argv[i], "-h") == 0 || strcmp(argv[i], "--help") == 0)
 194         {
 195             fprintf(stderr, "OpenAL Tone Generator\n"
 196 "\n"
 197 "Usage: %s [-device <name>] <options>\n"
 198 "\n"
 199 "Available options:\n"
 200 "  --help/-h                 This help text\n"
 201 "  -t <seconds>              Time to play a tone (default 5 seconds)\n"
 202 "  --waveform/-w <type>      Waveform type: sine (default), square, sawtooth,\n"
 203 "                                triangle, impulse, noise\n"
 204 "  --freq/-f <hz>            Tone frequency (default 1000 hz)\n"
 205 "  --srate/-s <sample rate>  Sampling rate (default output rate)\n",
 206                 appname
 207             );
 208             CloseAL();
 209             return 1;
 210         }
 211         else if(i+1 < argc && strcmp(argv[i], "-t") == 0)
 212         {
 213             i++;
 214             max_loops = atoi(argv[i]) - 1;
 215         }
 216         else if(i+1 < argc && (strcmp(argv[i], "--waveform") == 0 || strcmp(argv[i], "-w") == 0))
 217         {
 218             i++;
 219             if(strcmp(argv[i], "sine") == 0)
 220                 wavetype = WT_Sine;
 221             else if(strcmp(argv[i], "square") == 0)
 222                 wavetype = WT_Square;
 223             else if(strcmp(argv[i], "sawtooth") == 0)
 224                 wavetype = WT_Sawtooth;
 225             else if(strcmp(argv[i], "triangle") == 0)
 226                 wavetype = WT_Triangle;
 227             else if(strcmp(argv[i], "impulse") == 0)
 228                 wavetype = WT_Impulse;
 229             else if(strcmp(argv[i], "noise") == 0)
 230                 wavetype = WT_WhiteNoise;
 231             else
 232                 fprintf(stderr, "Unhandled waveform: %s\n", argv[i]);
 233         }
 234         else if(i+1 < argc && (strcmp(argv[i], "--freq") == 0 || strcmp(argv[i], "-f") == 0))
 235         {
 236             i++;
 237             tone_freq = atoi(argv[i]);
 238             if(tone_freq < 1)
 239             {
 240                 fprintf(stderr, "Invalid tone frequency: %s (min: 1hz)\n", argv[i]);
 241                 tone_freq = 1;
 242             }
 243         }
 244         else if(i+1 < argc && (strcmp(argv[i], "--srate") == 0 || strcmp(argv[i], "-s") == 0))
 245         {
 246             i++;
 247             srate = atoi(argv[i]);
 248             if(srate < 40)
 249             {
 250                 fprintf(stderr, "Invalid sample rate: %s (min: 40hz)\n", argv[i]);
 251                 srate = 40;
 252             }
 253         }
 254     }
 255
 256     {
 257         ALCdevice *device = alcGetContextsDevice(alcGetCurrentContext());
 258         alcGetIntegerv(device, ALC_FREQUENCY, 1, &dev_rate);
 259         assert(alcGetError(device)==ALC_NO_ERROR && "Failed to get device sample rate");
 260     }
 261     if(srate < 0)
 262         srate = dev_rate;
 263
 264     /* Load the sound into a buffer. */
 265     buffer = CreateWave(wavetype, (ALuint)tone_freq, (ALuint)srate);
 266     if(!buffer)
 267     {
 268         CloseAL();
 269         return 1;
 270     }
 271
 272     printf("Playing %dhz %s-wave tone with %dhz sample rate and %dhz output, for %d second%s...\n",
 273            tone_freq, GetWaveTypeName(wavetype), srate, dev_rate, max_loops+1, max_loops?"s":"");
 274     fflush(stdout);
 275
 276     /* Create the source to play the sound with. */
 277     source = 0;
 278     alGenSources(1, &source);
 279     alSourcei(source, AL_BUFFER, (ALint)buffer);
 280     assert(alGetError()==AL_NO_ERROR && "Failed to setup sound source");
 281
 282     /* Play the sound for a while. */
 283     num_loops = 0;
 284     last_pos = 0;
 285     alSourcei(source, AL_LOOPING, (max_loops > 0) ? AL_TRUE : AL_FALSE);
 286     alSourcePlay(source);
 287     do {
 288         ALint pos;
 289         al_nssleep(10000000);
 290         alGetSourcei(source, AL_SAMPLE_OFFSET, &pos);
 291         alGetSourcei(source, AL_SOURCE_STATE, &state);
 292         if(pos < last_pos && state == AL_PLAYING)
 293         {
 294             ++num_loops;
 295             if(num_loops >= max_loops)
 296                 alSourcei(source, AL_LOOPING, AL_FALSE);
 297             printf("%d...\n", max_loops - num_loops + 1);
 298             fflush(stdout);
 299         }
 300         last_pos = pos;
 301     } while(alGetError() == AL_NO_ERROR && state == AL_PLAYING);
 302
 303     /* All done. Delete resources, and close OpenAL. */
 304     alDeleteSources(1, &source);
 305     alDeleteBuffers(1, &buffer);
 306
 307     /* Close up OpenAL. */
 308     CloseAL();
 309
 310     return 0;
 311 }