5 // these are imported from audio.c
6 extern uint16_t envelope_index;
7 extern float note_timbre;
8 extern float polyphony_rate;
10 voice_type voice = default_voice;
12 void set_voice(voice_type v) {
16 void voice_iterate() {
17 voice = (voice + 1) % number_of_voices;
20 void voice_deiterate() {
21 voice = (voice - 1 + number_of_voices) % number_of_voices;
24 float voice_envelope(float frequency) {
25 // envelope_index ranges from 0 to 0xFFFF, which is preserved at 880.0 Hz
26 uint16_t compensated_index = (uint16_t)((float)envelope_index * (880.0 / frequency));
30 note_timbre = TIMBRE_50;
36 switch (compensated_index) {
38 note_timbre = TIMBRE_12;
42 note_timbre = TIMBRE_25;
46 note_timbre = .25 + .125 + pow(((float)compensated_index - 20) / (200 - 20), 2)*.125;
57 switch (compensated_index) {
59 frequency = frequency / 4;
60 note_timbre = TIMBRE_12;
64 frequency = frequency / 2;
65 note_timbre = TIMBRE_12;
69 note_timbre = .125 - pow(((float)compensated_index - 20) / (200 - 20), 2)*.125;
78 // case octave_crunch:
79 // polyphony_rate = 0;
80 // switch (compensated_index) {
84 // frequency = frequency / 2;
85 // note_timbre = TIMBRE_12;
91 // frequency = frequency * 2;
92 // note_timbre = TIMBRE_12;
96 // note_timbre = TIMBRE_12;
102 // This slows the loop down a substantial amount, so higher notes may freeze
104 switch (compensated_index) {
109 // note_timbre = (sin((float)compensated_index/10000*OCS_SPEED) * OCS_AMP / 2) + .5;
110 // triangle wave is a bit faster
111 note_timbre = (float)abs((compensated_index*OCS_SPEED % 3000) - 1500) * ( OCS_AMP / 1500 ) + (1 - OCS_AMP) / 2;
116 case duty_octave_down:
118 note_timbre = (envelope_index % 2) * .125 + .375 * 2;
119 if ((envelope_index % 4) == 0)
121 if ((envelope_index % 8) == 0)
124 case delayed_vibrato:
126 note_timbre = TIMBRE_50;
127 #define VOICE_VIBRATO_DELAY 150
128 #define VOICE_VIBRATO_SPEED 50
129 switch (compensated_index) {
130 case 0 ... VOICE_VIBRATO_DELAY:
133 frequency = frequency * vibrato_lut[(int)fmod((((float)compensated_index - (VOICE_VIBRATO_DELAY + 1))/1000*VOICE_VIBRATO_SPEED), VIBRATO_LUT_LENGTH)];
137 // case delayed_vibrato_octave:
138 // polyphony_rate = 0;
139 // if ((envelope_index % 2) == 1) {
140 // note_timbre = 0.55;
142 // note_timbre = 0.45;
144 // #define VOICE_VIBRATO_DELAY 150
145 // #define VOICE_VIBRATO_SPEED 50
146 // switch (compensated_index) {
147 // case 0 ... VOICE_VIBRATO_DELAY:
150 // frequency = frequency * VIBRATO_LUT[(int)fmod((((float)compensated_index - (VOICE_VIBRATO_DELAY + 1))/1000*VOICE_VIBRATO_SPEED), VIBRATO_LUT_LENGTH)];
154 // case duty_fifth_down:
155 // note_timbre = 0.5;
156 // if ((envelope_index % 3) == 0)
157 // note_timbre = 0.75;
159 // case duty_fourth_down:
160 // note_timbre = 0.0;
161 // if ((envelope_index % 12) == 0)
162 // note_timbre = 0.75;
163 // if (((envelope_index % 12) % 4) != 1)
164 // note_timbre = 0.75;
166 // case duty_third_down:
167 // note_timbre = 0.5;
168 // if ((envelope_index % 5) == 0)
169 // note_timbre = 0.75;
171 // case duty_fifth_third_down:
172 // note_timbre = 0.5;
173 // if ((envelope_index % 5) == 0)
174 // note_timbre = 0.75;
175 // if ((envelope_index % 3) == 0)
176 // note_timbre = 0.25;