297 lines
		
	
	
		
			9.5 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			297 lines
		
	
	
		
			9.5 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
| /* Copyright 2016 Jack Humbert
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|  *
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|  * This program is free software: you can redistribute it and/or modify
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|  * it under the terms of the GNU General Public License as published by
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|  * the Free Software Foundation, either version 2 of the License, or
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|  * (at your option) any later version.
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|  *
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|  * This program is distributed in the hope that it will be useful,
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|  * but WITHOUT ANY WARRANTY; without even the implied warranty of
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|  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
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|  * GNU General Public License for more details.
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|  *
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|  * You should have received a copy of the GNU General Public License
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|  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
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|  */
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| #include "voices.h"
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| #include "audio.h"
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| #include "stdlib.h"
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| 
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| // these are imported from audio.c
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| extern uint16_t envelope_index;
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| extern float note_timbre;
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| extern float polyphony_rate;
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| extern bool glissando;
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| 
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| voice_type voice = default_voice;
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| 
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| void set_voice(voice_type v) {
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|     voice = v;
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| }
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| 
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| void voice_iterate() {
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|     voice = (voice + 1) % number_of_voices;
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| }
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| 
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| void voice_deiterate() {
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|     voice = (voice - 1 + number_of_voices) % number_of_voices;
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| }
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| 
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| float voice_envelope(float frequency) {
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|     // envelope_index ranges from 0 to 0xFFFF, which is preserved at 880.0 Hz
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|     __attribute__ ((unused))
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|     uint16_t compensated_index = (uint16_t)((float)envelope_index * (880.0 / frequency));
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| 
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|     switch (voice) {
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|         case default_voice:
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|             glissando = false;
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|             note_timbre = TIMBRE_50;
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|             polyphony_rate = 0;
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| 	        break;
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| 
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|     #ifdef AUDIO_VOICES
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| 
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|         case something:
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|             glissando = false;
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|             polyphony_rate = 0;
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|             switch (compensated_index) {
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|                 case 0 ... 9:
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|                     note_timbre = TIMBRE_12;
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|                     break;
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| 
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|                 case 10 ... 19:
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|                     note_timbre = TIMBRE_25;
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|                     break;
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| 
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|                 case 20 ... 200:
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|                     note_timbre = .125 + .125;
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|                     break;
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| 
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|                 default:
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|                     note_timbre = .125;
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|                     break;
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|             }
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|             break;
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| 
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|         case drums:
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|             glissando = false;
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|             polyphony_rate = 0;
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|                 // switch (compensated_index) {
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|                 //     case 0 ... 10:
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|                 //         note_timbre = 0.5;
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|                 //         break;
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|                 //     case 11 ... 20:
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|                 //         note_timbre = 0.5 * (21 - compensated_index) / 10;
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|                 //         break;
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|                 //     default:
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|                 //         note_timbre = 0;
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|                 //         break;
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|                 // }
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|                 // frequency = (rand() % (int)(frequency * 1.2 - frequency)) + (frequency * 0.8);
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| 
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|             if (frequency < 80.0) {
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| 
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|             } else if (frequency < 160.0) {
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| 
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|                 // Bass drum: 60 - 100 Hz
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|                 frequency = (rand() % (int)(40)) + 60;
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|                 switch (envelope_index) {
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|                     case 0 ... 10:
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|                         note_timbre = 0.5;
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|                         break;
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|                     case 11 ... 20:
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|                         note_timbre = 0.5 * (21 - envelope_index) / 10;
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|                         break;
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|                     default:
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|                         note_timbre = 0;
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|                         break;
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|                 }
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| 
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|             } else if (frequency < 320.0) {
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| 
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| 
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|                 // Snare drum: 1 - 2 KHz
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|                 frequency = (rand() % (int)(1000)) + 1000;
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|                 switch (envelope_index) {
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|                     case 0 ... 5:
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|                         note_timbre = 0.5;
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|                         break;
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|                     case 6 ... 20:
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|                         note_timbre = 0.5 * (21 - envelope_index) / 15;
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|                         break;
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|                     default:
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|                         note_timbre = 0;
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|                         break;
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|                 }
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| 
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|             } else if (frequency < 640.0) {
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| 
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|                 // Closed Hi-hat: 3 - 5 KHz
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|                 frequency = (rand() % (int)(2000)) + 3000;
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|                 switch (envelope_index) {
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|                     case 0 ... 15:
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|                         note_timbre = 0.5;
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|                         break;
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|                     case 16 ... 20:
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|                         note_timbre = 0.5 * (21 - envelope_index) / 5;
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|                         break;
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|                     default:
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|                         note_timbre = 0;
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|                         break;
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|                 }
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| 
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|             } else if (frequency < 1280.0) {
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| 
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|                 // Open Hi-hat: 3 - 5 KHz
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|                 frequency = (rand() % (int)(2000)) + 3000;
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|                 switch (envelope_index) {
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|                     case 0 ... 35:
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|                         note_timbre = 0.5;
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|                         break;
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|                     case 36 ... 50:
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|                         note_timbre = 0.5 * (51 - envelope_index) / 15;
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|                         break;
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|                     default:
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|                         note_timbre = 0;
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|                         break;
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|                 }
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| 
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|             }
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|             break;
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|         case butts_fader:
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|             glissando = true;
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|             polyphony_rate = 0;
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|             switch (compensated_index) {
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|                 case 0 ... 9:
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|                     frequency = frequency / 4;
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|                     note_timbre = TIMBRE_12;
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| 	                break;
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| 
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|                 case 10 ... 19:
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|                     frequency = frequency / 2;
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|                     note_timbre = TIMBRE_12;
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| 	                break;
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| 
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|                 case 20 ... 200:
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|                     note_timbre = .125 - pow(((float)compensated_index - 20) / (200 - 20), 2)*.125;
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| 	                break;
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| 
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|                 default:
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|                     note_timbre = 0;
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|                 	break;
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|             }
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|     	    break;
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| 
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|         // case octave_crunch:
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|         //     polyphony_rate = 0;
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|         //     switch (compensated_index) {
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|         //         case 0 ... 9:
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|         //         case 20 ... 24:
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|         //         case 30 ... 32:
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|         //             frequency = frequency / 2;
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|         //             note_timbre = TIMBRE_12;
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|         //         break;
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| 
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|         //         case 10 ... 19:
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|         //         case 25 ... 29:
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|         //         case 33 ... 35:
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|         //             frequency = frequency * 2;
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|         //             note_timbre = TIMBRE_12;
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| 	       //          break;
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| 
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|         //         default:
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|         //             note_timbre = TIMBRE_12;
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|         //         	break;
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|         //     }
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| 	       //  break;
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| 
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|         case duty_osc:
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|             // This slows the loop down a substantial amount, so higher notes may freeze
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|             glissando = true;
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|             polyphony_rate = 0;
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|             switch (compensated_index) {
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|                 default:
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|                     #define OCS_SPEED 10
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|                     #define OCS_AMP   .25
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|                     // sine wave is slow
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|                     // note_timbre = (sin((float)compensated_index/10000*OCS_SPEED) * OCS_AMP / 2) + .5;
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|                     // triangle wave is a bit faster
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|                     note_timbre = (float)abs((compensated_index*OCS_SPEED % 3000) - 1500) * ( OCS_AMP / 1500 ) + (1 - OCS_AMP) / 2;
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|                 	break;
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|             }
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| 	        break;
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| 
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|         case duty_octave_down:
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|             glissando = true;
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|             polyphony_rate = 0;
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|             note_timbre = (envelope_index % 2) * .125 + .375 * 2;
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|             if ((envelope_index % 4) == 0)
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|                 note_timbre = 0.5;
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|             if ((envelope_index % 8) == 0)
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|                 note_timbre = 0;
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|             break;
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|         case delayed_vibrato:
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|             glissando = true;
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|             polyphony_rate = 0;
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|             note_timbre = TIMBRE_50;
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|             #define VOICE_VIBRATO_DELAY 150
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|             #define VOICE_VIBRATO_SPEED 50
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|             switch (compensated_index) {
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|                 case 0 ... VOICE_VIBRATO_DELAY:
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|                     break;
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|                 default:
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|                     frequency = frequency * vibrato_lut[(int)fmod((((float)compensated_index - (VOICE_VIBRATO_DELAY + 1))/1000*VOICE_VIBRATO_SPEED), VIBRATO_LUT_LENGTH)];
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|                     break;
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|             }
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|             break;
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|         // case delayed_vibrato_octave:
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|         //     polyphony_rate = 0;
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|         //     if ((envelope_index % 2) == 1) {
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|         //         note_timbre = 0.55;
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|         //     } else {
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|         //         note_timbre = 0.45;
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|         //     }
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|         //     #define VOICE_VIBRATO_DELAY 150
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|         //     #define VOICE_VIBRATO_SPEED 50
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|         //     switch (compensated_index) {
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|         //         case 0 ... VOICE_VIBRATO_DELAY:
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|         //             break;
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|         //         default:
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|         //             frequency = frequency * VIBRATO_LUT[(int)fmod((((float)compensated_index - (VOICE_VIBRATO_DELAY + 1))/1000*VOICE_VIBRATO_SPEED), VIBRATO_LUT_LENGTH)];
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|         //             break;
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|         //     }
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|         //     break;
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|         // case duty_fifth_down:
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|         //     note_timbre = 0.5;
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|         //     if ((envelope_index % 3) == 0)
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|         //         note_timbre = 0.75;
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|         //     break;
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|         // case duty_fourth_down:
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|         //     note_timbre = 0.0;
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|         //     if ((envelope_index % 12) == 0)
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|         //         note_timbre = 0.75;
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|         //     if (((envelope_index % 12) % 4) != 1)
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|         //         note_timbre = 0.75;
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|         //     break;
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|         // case duty_third_down:
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|         //     note_timbre = 0.5;
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|         //     if ((envelope_index % 5) == 0)
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|         //         note_timbre = 0.75;
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|         //     break;
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|         // case duty_fifth_third_down:
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|         //     note_timbre = 0.5;
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|         //     if ((envelope_index % 5) == 0)
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|         //         note_timbre = 0.75;
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|         //     if ((envelope_index % 3) == 0)
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|         //         note_timbre = 0.25;
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|         //     break;
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| 
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|     #endif
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| 
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| 		default:
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|    			break;
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|     }
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| 
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|     return frequency;
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| }
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