ladybird/Applications/Piano/PianoWidget.cpp
2019-12-25 16:14:11 +01:00

559 lines
16 KiB
C++

#include "PianoWidget.h"
#include <AK/Queue.h>
#include <LibDraw/GraphicsBitmap.h>
#include <LibGUI/GPainter.h>
#include <math.h>
PianoWidget::PianoWidget()
{
set_font(Font::default_fixed_width_font());
}
PianoWidget::~PianoWidget()
{
}
void PianoWidget::paint_event(GPaintEvent& event)
{
GPainter painter(*this);
painter.add_clip_rect(event.rect());
painter.fill_rect(event.rect(), Color::Black);
render_wave(painter);
render_piano(painter);
render_knobs(painter);
render_roll(painter);
}
void PianoWidget::fill_audio_buffer(uint8_t* stream, int len)
{
if (++m_time == m_tick) {
m_time = 0;
change_roll_column();
}
m_sample_count = len / sizeof(Sample);
memset(stream, 0, len);
auto* sst = (Sample*)stream;
for (int i = 0; i < m_sample_count; ++i) {
static const double volume = 1800;
for (size_t n = 0; n < (sizeof(m_note_on) / sizeof(u8)); ++n) {
if (!m_note_on[n])
continue;
double val = 0;
switch (m_wave_type) {
case WaveType::Sine:
val = ((volume * m_power[n]) * w_sine(n));
break;
case WaveType::Saw:
val = ((volume * m_power[n]) * w_saw(n));
break;
case WaveType::Square:
val = ((volume * m_power[n]) * w_square(n));
break;
case WaveType::Triangle:
val = ((volume * m_power[n]) * w_triangle(n));
break;
case WaveType::Noise:
val = ((volume * m_power[n]) * w_noise());
break;
}
sst[i].left += val;
}
sst[i].right = sst[i].left;
}
// Decay pressed notes.
if (m_decay_enabled) {
for (size_t n = 0; n < (sizeof(m_note_on) / sizeof(u8)); ++n) {
if (m_note_on[n])
m_power[n] *= 0.965;
}
}
static Queue<Sample*> delay_frames;
static const int delay_length_in_frames = m_tick * 4;
if (m_delay_enabled) {
if (delay_frames.size() >= delay_length_in_frames) {
auto* to_blend = delay_frames.dequeue();
for (int i = 0; i < m_sample_count; ++i) {
sst[i].left += to_blend[i].left * 0.333333;
sst[i].right += to_blend[i].right * 0.333333;
}
delete[] to_blend;
}
Sample* frame = new Sample[m_sample_count];
memcpy(frame, sst, m_sample_count * sizeof(Sample));
delay_frames.enqueue(frame);
}
ASSERT(len <= 2048 * (int)sizeof(Sample));
memcpy(m_back_buffer, (Sample*)stream, len);
swap(m_front_buffer, m_back_buffer);
}
double PianoWidget::w_sine(size_t n)
{
double pos = note_frequency[n] / 44100.0;
double sin_step = pos * 2 * M_PI;
double w = sin(m_sin_pos[n]);
m_sin_pos[n] += sin_step;
return w;
}
static inline double hax_floor(double t)
{
return (int)t;
}
double PianoWidget::w_saw(size_t n)
{
double saw_step = note_frequency[n] / 44100.0;
double t = m_saw_pos[n];
double w = (0.5 - (t - hax_floor(t))) * 2;
//printf("w: %g, step: %g\n", w, saw_step);
m_saw_pos[n] += saw_step;
return w;
}
double PianoWidget::w_square(size_t n)
{
double pos = note_frequency[n] / 44100.0;
double square_step = pos * 2 * M_PI;
double w = sin(m_square_pos[n]);
if (w > 0)
w = 1;
else
w = -1;
//printf("w: %g, step: %g\n", w, square_step);
m_square_pos[n] += square_step;
return w;
}
double PianoWidget::w_triangle(size_t n)
{
double triangle_step = note_frequency[n] / 44100.0;
double t = m_triangle_pos[n];
double w = fabs(fmod((4 * t) + 1, 4) - 2) - 1;
m_triangle_pos[n] += triangle_step;
return w;
}
double PianoWidget::w_noise()
{
return (((double)rand() / RAND_MAX) * 2.0) - 1.0;
}
int PianoWidget::octave_base() const
{
return (m_octave - m_octave_min) * 12;
}
struct KeyDefinition {
int index;
PianoKey piano_key;
String label;
KeyCode key_code;
};
const KeyDefinition key_definitions[] = {
{ 0, K_C1, "A", KeyCode::Key_A },
{ 1, K_D1, "S", KeyCode::Key_S },
{ 2, K_E1, "D", KeyCode::Key_D },
{ 3, K_F1, "F", KeyCode::Key_F },
{ 4, K_G1, "G", KeyCode::Key_G },
{ 5, K_A1, "H", KeyCode::Key_H },
{ 6, K_B1, "J", KeyCode::Key_J },
{ 7, K_C2, "K", KeyCode::Key_K },
{ 8, K_D2, "L", KeyCode::Key_L },
{ 9, K_E2, ";", KeyCode::Key_Semicolon },
{ 10, K_F2, "'", KeyCode::Key_Apostrophe },
{ 11, K_G2, "r", KeyCode::Key_Return },
{ 0, K_Db1, "W", KeyCode::Key_W },
{ 1, K_Eb1, "E", KeyCode::Key_E },
{ 3, K_Gb1, "T", KeyCode::Key_T },
{ 4, K_Ab1, "Y", KeyCode::Key_Y },
{ 5, K_Bb1, "U", KeyCode::Key_U },
{ 7, K_Db2, "O", KeyCode::Key_O },
{ 8, K_Eb2, "P", KeyCode::Key_P },
{ 10, K_Gb2, "]", KeyCode::Key_RightBracket },
};
void PianoWidget::note(KeyCode key_code, SwitchNote switch_note)
{
for (auto& kd : key_definitions) {
if (kd.key_code == key_code) {
note(kd.piano_key, switch_note);
return;
}
}
}
void PianoWidget::note(PianoKey piano_key, SwitchNote switch_note)
{
int n = octave_base() + piano_key;
if (switch_note == On) {
if (m_note_on[n] == 0) {
m_sin_pos[n] = 0;
m_square_pos[n] = 0;
m_saw_pos[n] = 0;
m_triangle_pos[n] = 0;
}
++m_note_on[n];
m_power[n] = 1;
} else {
if (m_note_on[n] > 1) {
--m_note_on[n];
} else if (m_note_on[n] == 1) {
--m_note_on[n];
m_power[n] = 0;
}
}
}
void PianoWidget::keydown_event(GKeyEvent& event)
{
if (keys[event.key()])
return;
keys[event.key()] = true;
switch (event.key()) {
case KeyCode::Key_C:
if (++m_wave_type == InvalidWave)
m_wave_type = 0;
break;
case KeyCode::Key_V:
m_delay_enabled = !m_delay_enabled;
break;
case KeyCode::Key_B:
m_decay_enabled = !m_decay_enabled;
break;
case KeyCode::Key_Z:
if (m_octave > m_octave_min)
--m_octave;
memset(m_note_on, 0, sizeof(m_note_on));
break;
case KeyCode::Key_X:
if (m_octave < m_octave_max)
++m_octave;
memset(m_note_on, 0, sizeof(m_note_on));
break;
default:
note((KeyCode)event.key(), On);
}
update();
}
void PianoWidget::keyup_event(GKeyEvent& event)
{
keys[event.key()] = false;
note((KeyCode)event.key(), Off);
update();
}
void PianoWidget::mousedown_event(GMouseEvent& event)
{
m_mouse_pressed = true;
m_piano_key_under_mouse = find_key_for_relative_position(event.x() - x(), event.y() - y());
if (m_piano_key_under_mouse) {
note(m_piano_key_under_mouse, On);
update();
return;
}
RollNote* roll_note_under_mouse = find_roll_note_for_relative_position(event.x() - x(), event.y() - y());
if (roll_note_under_mouse)
roll_note_under_mouse->pressed = !roll_note_under_mouse->pressed;
update();
}
void PianoWidget::mouseup_event(GMouseEvent&)
{
m_mouse_pressed = false;
note(m_piano_key_under_mouse, Off);
update();
}
void PianoWidget::mousemove_event(GMouseEvent& event)
{
if (!m_mouse_pressed)
return;
PianoKey mouse_was_over = m_piano_key_under_mouse;
m_piano_key_under_mouse = find_key_for_relative_position(event.x() - x(), event.y() - y());
if (m_piano_key_under_mouse == mouse_was_over)
return;
if (mouse_was_over)
note(mouse_was_over, Off);
if (m_piano_key_under_mouse)
note(m_piano_key_under_mouse, On);
update();
}
void PianoWidget::render_wave(GPainter& painter)
{
Color wave_color;
switch (m_wave_type) {
case WaveType::Sine:
wave_color = Color(255, 192, 0);
break;
case WaveType::Saw:
wave_color = Color(240, 100, 128);
break;
case WaveType::Square:
wave_color = Color(128, 160, 255);
break;
case WaveType::Triangle:
wave_color = Color(35, 171, 35);
break;
case WaveType::Noise:
wave_color = Color(197, 214, 225);
break;
}
int prev_x = 0;
int prev_y = m_height / 2;
for (int x = 0; x < m_sample_count; ++x) {
double val = m_front_buffer[x].left;
val /= 32768;
val *= m_height;
int y = ((m_height / 8) - 8) + val;
if (x == 0)
painter.set_pixel({ x, y }, wave_color);
else
painter.draw_line({ prev_x, prev_y }, { x, y }, wave_color);
prev_x = x;
prev_y = y;
}
}
static int white_key_width = 22;
static int white_key_height = 60;
static int black_key_width = 16;
static int black_key_height = 35;
static int black_key_stride = white_key_width - black_key_width;
static int black_key_offset = white_key_width - black_key_width / 2;
Rect PianoWidget::define_piano_key_rect(int index, PianoKey n) const
{
Rect rect;
int stride = 0;
int offset = 0;
if (is_white(n)) {
rect.set_width(white_key_width);
rect.set_height(white_key_height);
} else {
rect.set_width(black_key_width);
rect.set_height(black_key_height);
stride = black_key_stride;
offset = black_key_offset;
}
rect.set_x(offset + index * rect.width() + (index * stride));
rect.set_y(m_height - white_key_height);
return rect;
}
PianoKey PianoWidget::find_key_for_relative_position(int x, int y) const
{
// here we iterate backwards because we want to try to match the black
// keys first, which are defined last
for (int i = (sizeof(key_definitions) / sizeof(KeyDefinition)) - 1; i >= 0; i--) {
auto& kd = key_definitions[i];
auto rect = define_piano_key_rect(kd.index, kd.piano_key);
if (rect.contains(x, y))
return kd.piano_key;
}
return K_None;
}
void PianoWidget::render_piano_key(GPainter& painter, int index, PianoKey n, const StringView& text)
{
Color color;
if (m_note_on[octave_base() + n]) {
color = Color(64, 64, 255);
} else {
if (is_white(n))
color = Color::White;
else
color = Color::Black;
}
auto rect = define_piano_key_rect(index, n);
painter.fill_rect(rect, color);
painter.draw_rect(rect, Color::Black);
Color text_color;
if (is_white(n)) {
text_color = Color::Black;
} else {
text_color = Color::White;
}
Rect r(rect.x(), rect.y() + rect.height() / 2, rect.width(), rect.height() / 2);
painter.draw_text(r, text, TextAlignment::Center, text_color);
}
void PianoWidget::render_piano(GPainter& painter)
{
for (auto& kd : key_definitions)
render_piano_key(painter, kd.index, kd.piano_key, kd.label);
}
static int knob_width = 100;
void PianoWidget::render_knob(GPainter& painter, const Rect& rect, bool state, const StringView& text)
{
Color text_color;
if (state) {
painter.fill_rect(rect, Color(0, 200, 0));
text_color = Color::Black;
} else {
painter.draw_rect(rect, Color(180, 0, 0));
text_color = Color(180, 0, 0);
}
painter.draw_text(rect, text, TextAlignment::Center, text_color);
}
void PianoWidget::render_knobs(GPainter& painter)
{
Rect delay_knob_rect(m_width - knob_width - 16, m_height - 50, knob_width, 16);
render_knob(painter, delay_knob_rect, m_delay_enabled, "V: Delay ");
Rect decay_knob_rect(m_width - knob_width - 16, m_height - 30, knob_width, 16);
render_knob(painter, decay_knob_rect, m_decay_enabled, "B: Decay ");
Rect octave_knob_rect(m_width - knob_width - 16 - knob_width - 16, m_height - 50, knob_width, 16);
auto text = String::format("Z/X: Oct %d ", m_octave);
int oct_rgb_step = 255 / (m_octave_max + 4);
int oshade = (m_octave + 4) * oct_rgb_step;
painter.draw_rect(octave_knob_rect, Color(oshade, oshade, oshade));
painter.draw_text(octave_knob_rect, text, TextAlignment::Center, Color(oshade, oshade, oshade));
Rect wave_knob_rect(m_width - knob_width - 16 - knob_width - 16, m_height - 30, knob_width, 16);
switch (m_wave_type) {
case WaveType::Sine:
painter.draw_rect(wave_knob_rect, Color(255, 192, 0));
painter.draw_text(wave_knob_rect, "C: Sine ", TextAlignment::Center, Color(255, 192, 0));
break;
case WaveType::Saw:
painter.draw_rect(wave_knob_rect, Color(240, 100, 128));
painter.draw_text(wave_knob_rect, "C: Sawtooth", TextAlignment::Center, Color(240, 100, 128));
break;
case WaveType::Square:
painter.draw_rect(wave_knob_rect, Color(128, 160, 255));
painter.draw_text(wave_knob_rect, "C: Square ", TextAlignment::Center, Color(128, 160, 255));
break;
case WaveType::Triangle:
painter.draw_rect(wave_knob_rect, Color(35, 171, 35));
painter.draw_text(wave_knob_rect, "C: Triangle", TextAlignment::Center, Color(35, 171, 35));
break;
case WaveType::Noise:
painter.draw_rect(wave_knob_rect, Color(197, 214, 225));
painter.draw_text(wave_knob_rect, "C: Noise ", TextAlignment::Center, Color(197, 214, 225));
break;
}
}
static int roll_columns = 32;
static int roll_rows = 20;
static int roll_note_size = 512 / roll_columns;
static int roll_height = roll_note_size * roll_rows;
static int roll_y = 512 - white_key_height - roll_height - 16;
Rect PianoWidget::define_roll_note_rect(int column, int row) const
{
Rect rect;
rect.set_width(roll_note_size);
rect.set_height(roll_note_size);
rect.set_x(column * roll_note_size);
rect.set_y(roll_y + (row * roll_note_size));
return rect;
}
PianoWidget::RollNote* PianoWidget::find_roll_note_for_relative_position(int x, int y)
{
for (int row = 0; row < roll_rows; ++row) {
for (int column = 0; column < roll_columns; ++column) {
auto rect = define_roll_note_rect(column, row);
if (rect.contains(x, y))
return &m_roll_notes[row][column];
}
}
return nullptr;
}
void PianoWidget::render_roll_note(GPainter& painter, int column, int row, PianoKey key)
{
Color color;
auto roll_note = m_roll_notes[row][column];
if (roll_note.pressed) {
if (roll_note.playing)
color = Color(24, 24, 255);
else
color = Color(64, 64, 255);
} else {
if (roll_note.playing)
color = Color(104, 104, 255);
else
color = is_white(key) ? Color::White : Color::MidGray;
}
auto rect = define_roll_note_rect(column, row);
painter.fill_rect(rect, color);
painter.draw_rect(rect, Color::Black);
}
void PianoWidget::render_roll(GPainter& painter)
{
for (int row = 0; row < roll_rows; ++row) {
PianoKey key = (PianoKey)(roll_rows - row);
for (int column = 0; column < roll_columns; ++column)
render_roll_note(painter, column, row, key);
}
}
void PianoWidget::change_roll_column()
{
static int current_column = 0;
static int previous_column = roll_columns - 1;
for (int row = 0; row < roll_rows; ++row) {
m_roll_notes[row][previous_column].playing = false;
if (m_roll_notes[row][previous_column].pressed)
note((PianoKey)(roll_rows - row), Off);
m_roll_notes[row][current_column].playing = true;
if (m_roll_notes[row][current_column].pressed)
note((PianoKey)(roll_rows - row), On);
}
if (++current_column == roll_columns)
current_column = 0;
if (++previous_column == roll_columns)
previous_column = 0;
update();
}
void PianoWidget::custom_event(CCustomEvent&)
{
update();
}