5 // these are imported from audio.c
6 extern uint16_t envelope_index;
7 extern float note_timbre;
8 extern float polyphony_rate;
11 voice_type voice = default_voice;
13 void set_voice(voice_type v) {
17 void voice_iterate() {
18 voice = (voice + 1) % number_of_voices;
21 void voice_deiterate() {
22 voice = (voice - 1 + number_of_voices) % number_of_voices;
25 float voice_envelope(float frequency) {
26 // envelope_index ranges from 0 to 0xFFFF, which is preserved at 880.0 Hz
27 __attribute__ ((unused))
28 uint16_t compensated_index = (uint16_t)((float)envelope_index * (880.0 / frequency));
33 note_timbre = TIMBRE_50;
42 switch (compensated_index) {
44 note_timbre = TIMBRE_12;
48 note_timbre = TIMBRE_25;
52 note_timbre = .125 + .125;
64 // switch (compensated_index) {
69 // note_timbre = 0.5 * (21 - compensated_index) / 10;
75 // frequency = (rand() % (int)(frequency * 1.2 - frequency)) + (frequency * 0.8);
77 if (frequency < 80.0) {
79 } else if (frequency < 160.0) {
81 // Bass drum: 60 - 100 Hz
82 frequency = (rand() % (int)(40)) + 60;
83 switch (envelope_index) {
88 note_timbre = 0.5 * (21 - envelope_index) / 10;
95 } else if (frequency < 320.0) {
98 // Snare drum: 1 - 2 KHz
99 frequency = (rand() % (int)(1000)) + 1000;
100 switch (envelope_index) {
105 note_timbre = 0.5 * (21 - envelope_index) / 15;
112 } else if (frequency < 640.0) {
114 // Closed Hi-hat: 3 - 5 KHz
115 frequency = (rand() % (int)(2000)) + 3000;
116 switch (envelope_index) {
121 note_timbre = 0.5 * (21 - envelope_index) / 5;
128 } else if (frequency < 1280.0) {
130 // Open Hi-hat: 3 - 5 KHz
131 frequency = (rand() % (int)(2000)) + 3000;
132 switch (envelope_index) {
137 note_timbre = 0.5 * (51 - envelope_index) / 15;
149 switch (compensated_index) {
151 frequency = frequency / 4;
152 note_timbre = TIMBRE_12;
156 frequency = frequency / 2;
157 note_timbre = TIMBRE_12;
161 note_timbre = .125 - pow(((float)compensated_index - 20) / (200 - 20), 2)*.125;
170 // case octave_crunch:
171 // polyphony_rate = 0;
172 // switch (compensated_index) {
176 // frequency = frequency / 2;
177 // note_timbre = TIMBRE_12;
183 // frequency = frequency * 2;
184 // note_timbre = TIMBRE_12;
188 // note_timbre = TIMBRE_12;
194 // This slows the loop down a substantial amount, so higher notes may freeze
197 switch (compensated_index) {
202 // note_timbre = (sin((float)compensated_index/10000*OCS_SPEED) * OCS_AMP / 2) + .5;
203 // triangle wave is a bit faster
204 note_timbre = (float)abs((compensated_index*OCS_SPEED % 3000) - 1500) * ( OCS_AMP / 1500 ) + (1 - OCS_AMP) / 2;
209 case duty_octave_down:
212 note_timbre = (envelope_index % 2) * .125 + .375 * 2;
213 if ((envelope_index % 4) == 0)
215 if ((envelope_index % 8) == 0)
218 case delayed_vibrato:
221 note_timbre = TIMBRE_50;
222 #define VOICE_VIBRATO_DELAY 150
223 #define VOICE_VIBRATO_SPEED 50
224 switch (compensated_index) {
225 case 0 ... VOICE_VIBRATO_DELAY:
228 frequency = frequency * vibrato_lut[(int)fmod((((float)compensated_index - (VOICE_VIBRATO_DELAY + 1))/1000*VOICE_VIBRATO_SPEED), VIBRATO_LUT_LENGTH)];
232 // case delayed_vibrato_octave:
233 // polyphony_rate = 0;
234 // if ((envelope_index % 2) == 1) {
235 // note_timbre = 0.55;
237 // note_timbre = 0.45;
239 // #define VOICE_VIBRATO_DELAY 150
240 // #define VOICE_VIBRATO_SPEED 50
241 // switch (compensated_index) {
242 // case 0 ... VOICE_VIBRATO_DELAY:
245 // frequency = frequency * VIBRATO_LUT[(int)fmod((((float)compensated_index - (VOICE_VIBRATO_DELAY + 1))/1000*VOICE_VIBRATO_SPEED), VIBRATO_LUT_LENGTH)];
249 // case duty_fifth_down:
250 // note_timbre = 0.5;
251 // if ((envelope_index % 3) == 0)
252 // note_timbre = 0.75;
254 // case duty_fourth_down:
255 // note_timbre = 0.0;
256 // if ((envelope_index % 12) == 0)
257 // note_timbre = 0.75;
258 // if (((envelope_index % 12) % 4) != 1)
259 // note_timbre = 0.75;
261 // case duty_third_down:
262 // note_timbre = 0.5;
263 // if ((envelope_index % 5) == 0)
264 // note_timbre = 0.75;
266 // case duty_fifth_third_down:
267 // note_timbre = 0.5;
268 // if ((envelope_index % 5) == 0)
269 // note_timbre = 0.75;
270 // if ((envelope_index % 3) == 0)
271 // note_timbre = 0.25;