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/*
* Copyright (c) 2018-2020, Andreas Kling <kling@serenityos.org>
* Copyright (c) 2019-2020, William McPherson <willmcpherson2@gmail.com>
*
* SPDX-License-Identifier: BSD-2-Clause
*/
#pragma once
#include <AK/Types.h>
#include <LibGfx/Color.h>
namespace Music {
// CD quality
// - Stereo
// - 16 bit
// - 44,100 samples/sec
// - 1,411.2 kbps
struct Sample {
i16 left;
i16 right;
};
// HACK: needs to increase with device sample rate, but all of the sample_count stuff is static for now
constexpr int sample_count = 1 << 10;
constexpr int buffer_size = sample_count * sizeof(Sample);
constexpr double sample_rate = 44100;
// Headroom for the synth
constexpr double volume_factor = 0.8;
enum Direction {
Down,
Up,
};
enum KeyColor {
White,
Black,
};
constexpr KeyColor key_pattern[] = {
White,
Black,
White,
Black,
White,
White,
Black,
White,
Black,
White,
Black,
White,
};
const Color note_pressed_color(64, 64, 255);
const Color column_playing_color(128, 128, 255);
const Color left_wave_colors[] = {
// Sine
{
255,
192,
0,
},
// Triangle
{
35,
171,
35,
},
// Square
{
128,
160,
255,
},
// Saw
{
240,
100,
128,
},
// Noise
{
197,
214,
225,
},
// RecordedSample
{
227,
39,
39,
},
};
// HACK: make the display code shut up for now
constexpr int RecordedSample = 5;
const Color right_wave_colors[] = {
// Sine
{
255,
223,
0,
},
// Triangle
{
35,
171,
90,
},
// Square
{
139,
128,
255,
},
// Saw
{
240,
100,
220,
},
// Noise
{
197,
223,
225,
},
// RecordedSample
{
227,
105,
39,
},
};
constexpr int notes_per_octave = 12;
constexpr int white_keys_per_octave = 7;
constexpr int black_keys_per_octave = 5;
constexpr int octave_min = 1;
constexpr int octave_max = 7;
constexpr int volume_max = 1000;
constexpr double beats_per_minute = 60;
constexpr int beats_per_bar = 4;
constexpr int notes_per_beat = 4;
constexpr int roll_length = (sample_rate / (beats_per_minute / 60)) * beats_per_bar;
constexpr char const* note_names[] = {
"C",
"C#",
"D",
"D#",
"E",
"F",
"F#",
"G",
"G#",
"A",
"A#",
"B",
};
// Equal temperament, A = 440Hz
// We calculate note frequencies relative to A4:
// 440.0 * pow(pow(2.0, 1.0 / 12.0), N)
// Where N is the note distance from A.
constexpr double note_frequencies[] = {
// Octave 1
32.703195662574764,
34.647828872108946,
36.708095989675876,
38.890872965260044,
41.203444614108669,
43.653528929125407,
46.249302838954222,
48.99942949771858,
51.913087197493056,
54.999999999999915,
58.270470189761156,
61.735412657015416,
// Octave 2
65.406391325149571,
69.295657744217934,
73.416191979351794,
77.781745930520117,
82.406889228217381,
87.307057858250872,
92.4986056779085,
97.998858995437217,
103.82617439498618,
109.99999999999989,
116.54094037952237,
123.4708253140309,
// Octave 3
130.8127826502992,
138.59131548843592,
146.83238395870364,
155.56349186104035,
164.81377845643485,
174.61411571650183,
184.99721135581709,
195.99771799087452,
207.65234878997245,
219.99999999999989,
233.08188075904488,
246.94165062806198,
// Octave 4
261.62556530059851,
277.18263097687202,
293.66476791740746,
311.12698372208081,
329.62755691286986,
349.22823143300383,
369.99442271163434,
391.99543598174927,
415.30469757994513,
440,
466.16376151808993,
493.88330125612413,
// Octave 5
523.25113060119736,
554.36526195374427,
587.32953583481526,
622.25396744416196,
659.25511382574007,
698.456462866008,
739.98884542326903,
783.99087196349899,
830.60939515989071,
880.00000000000034,
932.32752303618031,
987.76660251224882,
// Octave 6
1046.5022612023952,
1108.7305239074892,
1174.659071669631,
1244.5079348883246,
1318.5102276514808,
1396.9129257320169,
1479.977690846539,
1567.9817439269987,
1661.2187903197821,
1760.000000000002,
1864.6550460723618,
1975.5332050244986,
// Octave 7
2093.0045224047913,
2217.4610478149793,
2349.3181433392633,
2489.0158697766506,
2637.020455302963,
2793.8258514640347,
2959.9553816930793,
3135.9634878539991,
3322.437580639566,
3520.0000000000055,
3729.3100921447249,
3951.0664100489994,
};
constexpr int note_count = sizeof(note_frequencies) / sizeof(double);
constexpr double middle_c = note_frequencies[36];
}
using namespace Music;
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