aboutsummaryrefslogtreecommitdiffstats
path: root/quantum/audio/voices.c
blob: d2316ba1b3bfebf01c1e51bf7248e1bf2f8b5061 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
#include "voices.h"
#include "stdlib.h"
#include "vibrato_lut.h"

// these are imported from audio.c
extern uint16_t envelope_index;
extern float note_timbre;
extern float polyphony_rate;

voice_type voice = default_voice;

void set_voice(voice_type v) {
    voice = v;
}

void voice_iterate() {
    voice = (voice + 1) % number_of_voices;
}

void voice_deiterate() {
    voice = (voice - 1) % number_of_voices;
}

float voice_envelope(float frequency) {
    // envelope_index ranges from 0 to 0xFFFF, which is preserved at 880.0 Hz
    uint16_t compensated_index = (uint16_t)((float)envelope_index * (880.0 / frequency));

    switch (voice) {
        case default_voice:
            note_timbre = TIMBRE_50;
            polyphony_rate = 0;
	        break;

        case butts_fader:
            polyphony_rate = 0;
            switch (compensated_index) {
                case 0 ... 9:
                    frequency = frequency / 4;
                    note_timbre = TIMBRE_12;
	                break;

                case 10 ... 19:
                    frequency = frequency / 2;
                    note_timbre = TIMBRE_12;
	                break;

                case 20 ... 200:
                    note_timbre = .125 - pow(((float)compensated_index - 20) / (200 - 20), 2)*.125;
	                break;

                default:
                    note_timbre = 0;
                	break;
            }
    	    break;

        // case octave_crunch:
        //     polyphony_rate = 0;
        //     switch (compensated_index) {
        //         case 0 ... 9:
        //         case 20 ... 24:
        //         case 30 ... 32:
        //             frequency = frequency / 2;
        //             note_timbre = TIMBRE_12;
        //         break;

        //         case 10 ... 19:
        //         case 25 ... 29:
        //         case 33 ... 35:
        //             frequency = frequency * 2;
        //             note_timbre = TIMBRE_12;
	       //          break;

        //         default:
        //             note_timbre = TIMBRE_12;
        //         	break;
        //     }
	       //  break;

        case duty_osc:
            // This slows the loop down a substantial amount, so higher notes may freeze
            polyphony_rate = 0;
            switch (compensated_index) {
                default:
                    #define OCS_SPEED 10
                    #define OCS_AMP   .25
                    // sine wave is slow
                    // note_timbre = (sin((float)compensated_index/10000*OCS_SPEED) * OCS_AMP / 2) + .5;
                    // triangle wave is a bit faster
                    note_timbre = (float)abs((compensated_index*OCS_SPEED % 3000) - 1500) * ( OCS_AMP / 1500 ) + (1 - OCS_AMP) / 2;
                	break;
            }
	        break;

        case duty_octave_down:
            polyphony_rate = 0;
            note_timbre = (envelope_index % 2) * .125 + .375 * 2;
            if ((envelope_index % 4) == 0)
                note_timbre = 0.5;
            if ((envelope_index % 8) == 0)
                note_timbre = 0;
            break;
        case delayed_vibrato:
            polyphony_rate = 0;
            note_timbre = TIMBRE_50;
            #define VOICE_VIBRATO_DELAY 150
            #define VOICE_VIBRATO_SPEED 50
            switch (compensated_index) {
                case 0 ... VOICE_VIBRATO_DELAY:
                    break;
                default:
                    frequency = frequency * VIBRATO_LUT[(int)fmod((((float)compensated_index - (VOICE_VIBRATO_DELAY + 1))/1000*VOICE_VIBRATO_SPEED), VIBRATO_LUT_LENGTH)];
                    break;
            }
            break;
        // case delayed_vibrato_octave:
        //     polyphony_rate = 0;
        //     if ((envelope_index % 2) == 1) {
        //         note_timbre = 0.55;
        //     } else {
        //         note_timbre = 0.45;
        //     }
        //     #define VOICE_VIBRATO_DELAY 150
        //     #define VOICE_VIBRATO_SPEED 50
        //     switch (compensated_index) {
        //         case 0 ... VOICE_VIBRATO_DELAY:
        //             break;
        //         default:
        //             frequency = frequency * VIBRATO_LUT[(int)fmod((((float)compensated_index - (VOICE_VIBRATO_DELAY + 1))/1000*VOICE_VIBRATO_SPEED), VIBRATO_LUT_LENGTH)];
        //             break;
        //     }
        //     break;
        // case duty_fifth_down:
        //     note_timbre = 0.5;
        //     if ((envelope_index % 3) == 0)
        //         note_timbre = 0.75;
        //     break;
        // case duty_fourth_down:
        //     note_timbre = 0.0;
        //     if ((envelope_index % 12) == 0)
        //         note_timbre = 0.75;
        //     if (((envelope_index % 12) % 4) != 1)
        //         note_timbre = 0.75;
        //     break;
        // case duty_third_down:
        //     note_timbre = 0.5;
        //     if ((envelope_index % 5) == 0)
        //         note_timbre = 0.75;
        //     break;
        // case duty_fifth_third_down:
        //     note_timbre = 0.5;
        //     if ((envelope_index % 5) == 0)
        //         note_timbre = 0.75;
        //     if ((envelope_index % 3) == 0)
        //         note_timbre = 0.25;
        //     break;

		default:
   			break;
    }

    return frequency;
}