3 Ann Hell Ex Machina - Music Software
4 Copyright (C) 2003/2006 Angel Ortega <angel@triptico.com>
6 ss_ins.c - Software synthesizer's instruments
8 This program is free software; you can redistribute it and/or
9 modify it under the terms of the GNU General Public License
10 as published by the Free Software Foundation; either version 2
11 of the License, or (at your option) any later version.
13 This program is distributed in the hope that it will be useful,
14 but WITHOUT ANY WARRANTY; without even the implied warranty of
15 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
16 GNU General Public License for more details.
18 You should have received a copy of the GNU General Public License
19 along with this program; if not, write to the Free Software
20 Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
22 http://www.triptico.com
44 * ss_ins_init - Initializes an instrument.
47 * Initializes an instrument structure.
49 void ss_ins_init(struct ss_ins
* i
)
51 memset(i
, '\0', sizeof(struct ss_ins
));
53 /* default channels: stereo left and right, full volume */
54 ss_ins_set_channel(i
, 0, 1.0);
55 ss_ins_set_channel(i
, 1, 1.0);
57 /* sustain shouldn't be 0 to avoid end of note clicks */
58 ss_ins_set_sustain(i
, 50.0);
59 ss_ins_set_attack(i
, 0.0);
60 ss_ins_set_vibrato(i
, 0.0, 0.0);
61 ss_ins_set_portamento(i
, 0.0);
66 * ss_ins_disable - Disables an instrument.
69 * Disables an instrument. From now on, no more notes can be played
70 * on this instrument. If no note are left sounding, ss_ins_frame()
71 * will return immediately.
73 void ss_ins_disable(struct ss_ins
* i
)
80 * ss_ins_add_layer - Adds a layer to an instrument.
82 * @w: wave describing the layer
84 * Adds a layer to an instrument.
86 * Returns 0 if the layer was added successfully.
88 void ss_ins_add_layer(struct ss_ins
* i
, struct ss_wave
* w
)
91 GROW(i
->layers
, i
->n_layers
, struct ss_wave
*);
93 i
->layers
[i
->n_layers
] = w
;
100 * ss_ins_find_layer - Finds a layer inside an instrument
102 * @freq: the desired frequency
103 * @off: pointer to element offset to start searching
105 * Finds a layer inside the @i instrument with a matching @freq, starting
106 * from the layer number pointed by @off. If a matching layer is found, its
107 * struct ss_wave is returned and @off is left pointing to the next layer
108 * (allowing it to be used as an enumerator). If no layer is found, NULL
111 struct ss_wave
* ss_ins_find_layer(struct ss_ins
* i
, double freq
, int * off
)
114 struct ss_wave
* w
= NULL
;
116 /* if off is NULL, point to the first layer */
117 if(off
== NULL
) off
= &n
;
119 /* find a matching layer, starting from *off */
120 for(;*off
< i
->n_layers
;(*off
)++)
124 if(freq
>= w
->min_freq
&& freq
<= w
->max_freq
)
128 /* passed the end; none found */
129 if(*off
== i
->n_layers
)
139 * ss_ins_set_channel - Sets the volume for an instrument's channel.
141 * @channel: channel number
144 * Sets the volume for an instrument's channel. If the channel does
145 * not exist, it's created and space allocated for it in the volume and
146 * effect dynamic arrays.
148 void ss_ins_set_channel(struct ss_ins
* i
, int channel
, sample_t vol
)
150 /* if channel is new, alloc space for it */
151 if(channel
<= i
->n_channels
)
155 GROW(i
->vols
, channel
, sample_t
);
156 GROW(i
->effs
, channel
, struct ss_eff
*);
158 /* fill newly allocated space */
159 for(n
= i
->n_channels
;n
<= channel
;n
++)
165 i
->n_channels
= channel
+ 1;
169 i
->vols
[channel
] = vol
;
174 * ss_ins_set_sustain - Sets the sustain for an instrument.
176 * @sustain: the sustain time in milliseconds
178 * Sets the sustain for an instrument. @sustain is expressed in
181 void ss_ins_set_sustain(struct ss_ins
* i
, double sustain
)
183 i
->sustain
= sustain
;
188 * ss_ins_set_attack - Sets the attack for an instrument.
190 * @attack: the attack time in milliseconds
192 * Sets the attack for an instrument. @attack is expressed in
195 void ss_ins_set_attack(struct ss_ins
* i
, double attack
)
202 * ss_ins_set_vibrato - Sets the vibrato for an instrument.
204 * @depth: vibrato depth in msecs
205 * @freq: vibrato frequency in Hzs
207 * Sets the vibrato for an instrument. @depth is expressed in
208 * milliseconds and @freq in Hzs.
210 void ss_ins_set_vibrato(struct ss_ins
* i
, double depth
, double freq
)
212 i
->vib_depth
= depth
;
218 * ss_ins_set_portamento - Sets portamento for an instrument.
220 * @portamento: portamento value
222 * Sets portamento for an instrument.
224 void ss_ins_set_portamento(struct ss_ins
* i
, double portamento
)
226 i
->portamento
= portamento
;
231 * ss_ins_play - Plays a note given the desired wave.
238 * Orders the instrument to start playing a note, given a specific wave.
239 * The wave is usually one of the instrument's layers, but it doesn't
242 * Returns -1 if the instrument is disabled, -2 if no free generators
243 * were found, or 0 if everything went ok.
245 int ss_ins_play(struct ss_ins
* i
, double freq
, sample_t vol
, int note_id
,
250 /* if the instrument is disabled, no more notes are allowed */
251 if(i
->disabled
) return(-1);
253 /* get a free generator, or fail */
254 if((g
= ss_gen_alloc(&i
->gens
)) == NULL
)
257 /* start the generator */
258 ss_gen_play(g
, freq
, vol
, note_id
, w
);
260 /* set generator parameters */
261 ss_gen_sustain(g
, i
->sustain
);
262 ss_gen_attack(g
, i
->attack
);
263 ss_gen_vibrato(g
, i
->vib_depth
, i
->vib_freq
);
264 ss_gen_portamento(g
, i
->portamento
);
271 * ss_ins_note_on - Plays a note.
273 * @note: MIDI note to be played
277 * Locates a layer to play a note, and starts generators to
278 * play it. The @note is expressed as a MIDI note and the
279 * desired volume (from 0 to 1) stored in @vol. The note @id
280 * should be a positive, unique identifier for this note; no two
281 * simultaneously playing notes should share this id.
283 * Returns the number of generators that were activated.
285 int ss_ins_note_on(struct ss_ins
* i
, int note
, sample_t vol
, int note_id
)
291 freq
= ss_note_frequency(note
);
293 for(n
= g
= 0;(w
=ss_ins_find_layer(i
, freq
, &n
)) != NULL
;g
++)
295 if(ss_ins_play(i
, freq
, vol
, note_id
, w
) < 0)
304 * ss_ins_note_off - Releases a note.
306 * @note_id: the id of the note to be released
308 * Releases a note. The generators associated to it will enter release mode.
310 void ss_ins_note_off(struct ss_ins
* i
, int note_id
)
314 /* releases all generators with that note_id */
315 for(g
= i
->gens
;g
!= NULL
;g
= g
->next
)
317 if(g
->note_id
== note_id
)
324 * ss_ins_frame - Generates a frame of samples.
326 * @frame: array where the output samples will be stored
328 * Generates a frame of samples mixing all the active generators
331 * Returns 0 if the instrument is disabled and is no longer
332 * emitting sound, or 1 otherwise.
334 int ss_ins_frame(struct ss_ins
* i
, sample_t frame
[])
339 sample_t l_frame
[SS_MAX_CHANNELS
];
341 /* if instrument is disabled and there is no more generators, exit */
342 if(i
->disabled
&& i
->gens
== NULL
)
344 /* reset all effects */
345 for(n
= 0;n
< i
->n_channels
;n
++)
346 ss_eff_off(&i
->effs
[n
]);
351 /* resets this local frame */
352 ss_output_init_frame(l_frame
);
354 /* loops through the generators */
355 for(g
= i
->gens
;g
!= NULL
;g
= t
)
359 /* if the generator has stopped, free it */
360 if(ss_gen_frame(g
, i
->n_channels
, l_frame
))
361 ss_gen_free(&i
->gens
, g
);
364 /* loops through the effects and remixes */
365 for(n
= 0;n
< i
->n_channels
;n
++)
366 frame
[n
] += ss_eff_process(i
->effs
[n
],
367 l_frame
[n
] * i
->vols
[n
]);