ss_gen.h

   1 /*
   2
   3     Ann Hell Ex Machina - Music Software
   4     Copyright (C) 2003/2004 Angel Ortega <angel@triptico.com>
   5
   6     This program is free software; you can redistribute it and/or
   7     modify it under the terms of the GNU General Public License
   8     as published by the Free Software Foundation; either version 2
   9     of the License, or (at your option) any later version.
  10
  11     This program is distributed in the hope that it will be useful,
  12     but WITHOUT ANY WARRANTY; without even the implied warranty of
  13     MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14     GNU General Public License for more details.
  15
  16     You should have received a copy of the GNU General Public License
  17     along with this program; if not, write to the Free Software
  18     Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.
  19
  20     http://www.triptico.com
  21
  22 */
  23
  24 /*
  25
  26 generator modes:
  27
  28 SS_GEN_PLAYING - Generator is generating sound after a call
  29         to generator_play(). If sound is not looped, jumps
  30         to SS_GEN_ZOMBIE when the cursor reaches loop_end.
  31
  32 SS_GEN_RELEASED - Generator is generating the sustain of a sound
  33         after a call to generator_release(). When the sustain
  34         ends, jumps to SS_GEN_FREE.
  35
  36 SS_GEN_ZOMBIE - Generator was playing a non-looped sound and the
  37         cursor got beyond loop_end. No sound is being generated.
  38         Waiting for a call to generator_release() to enter
  39         SS_GEN_FREE immediately.
  40
  41 SS_GEN_FREE - Generator is free to be used.
  42
  43 */
  44
  45 #ifndef SS_GEN_NUM
  46 #define SS_GEN_NUM      256
  47 #endif
  48
  49 #define SS_GEN_PLAYING  3
  50 #define SS_GEN_RELEASED 2
  51 #define SS_GEN_FREE     0
  52
  53 struct ss_gen
  54 {
  55         int mode;               /* SS_GEN_* */
  56
  57         int note_id;            /* note ID */
  58         int trk_id;             /* track ID */
  59
  60         float * wave[CHANNELS]; /* the PCM waves */
  61         float vol[CHANNELS];    /* the volumes */
  62
  63         double size;            /* size in samples */
  64         double loop_start;      /* start of loop (-1, no loop) */
  65         double loop_end;        /* end of loop */
  66
  67         double inc;             /* increment (frequency) */
  68         double cursor;          /* offset to next sample */
  69
  70         int sustain;            /* number of samples to play after release */
  71         float dvol[CHANNELS];   /* volume decrement for each sample in sustain */
  72
  73         int portamento;         /* number of samples of portamento */
  74         double dest_inc;        /* final portamento inc */
  75         double dinc;            /* delta of inc */
  76 };
  77
  78
  79 int ss_gen_play(int note_id, int trk_id, float * wave[], float vol[],
  80         double size, double inc, double loop_start, double loop_end,
  81         int sustain);
  82
  83 int ss_gen_release(int note_id);
  84
  85 int _ss_gen_frame(struct ss_gen * g, float frame[]);
  86
  87 void ss_gen_frame(int trk_id, float frame[]);
  88
  89 int ss_gen_portamento(struct ss_gen * g, int portamento, double dest_inc);