/*
  * This file is part of FFmpeg.
  *
  * FFmpeg is free software; you can redistribute it and/or
  * modify it under the terms of the GNU Lesser General Public
  * License as published by the Free Software Foundation; either
  * version 2.1 of the License, or (at your option) any later version.
  *
  * FFmpeg is distributed in the hope that it will be useful,
  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  * Lesser General Public License for more details.
  *
  * You should have received a copy of the GNU Lesser General Public
  * License along with FFmpeg; if not, write to the Free Software
  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
  */
 
 #include <stdint.h>
 #include "libavutil/avassert.h"
 #include "avfilter.h"
 #include "generate_wave_table.h"
 
 void ff_generate_wave_table(enum WaveType wave_type,
                             enum AVSampleFormat sample_fmt,
                             void *table, int table_size,
                             double min, double max, double phase)
 {
     uint32_t i, phase_offset = phase / M_PI / 2 * table_size + 0.5;
 
     for (i = 0; i < table_size; i++) {
         uint32_t point = (i + phase_offset) % table_size;
         double d;
 
         switch (wave_type) {
         case WAVE_SIN:
             d = (sin((double)point / table_size * 2 * M_PI) + 1) / 2;
             break;
         case WAVE_TRI:
             d = (double)point * 2 / table_size;
             switch (4 * point / table_size) {
             case 0: d = d + 0.5; break;
             case 1:
             case 2: d = 1.5 - d; break;
             case 3: d = d - 1.5; break;
             }
             break;
         default:
             av_assert0(0);
         }
 
         d  = d * (max - min) + min;
         switch (sample_fmt) {
         case AV_SAMPLE_FMT_FLT: {
             float *fp = (float *)table;
             *fp++ = (float)d;
             table = fp;
             continue; }
         case AV_SAMPLE_FMT_DBL: {
             double *dp = (double *)table;
             *dp++ = d;
             table = dp;
             continue; }
         }
 
         d += d < 0 ? -0.5 : 0.5;
         switch (sample_fmt) {
         case AV_SAMPLE_FMT_S16: {
             int16_t *sp = table;
             *sp++ = (int16_t)d;
             table = sp;
             continue; }
         case AV_SAMPLE_FMT_S32: {
             int32_t *ip = table;
             *ip++ = (int32_t)d;
             table = ip;
             continue; }
         default:
             av_assert0(0);
         }
     }
 }