Just checked in the new improvements. There is now a polyphonic piano demo. Only two notes can be sustained – if you touch at different screen heights – because of the touch-sensor limitation, but keys that were hit before keep sounding for a bit. Shows M5Sound has no problem with 14 concurrent Synth instances.
To make this satisfying, I needed to be able to move my finger from key to key (glissando), which M5Button didn't let me do. Enter M5.Buttons.pianoMode = true. Now you can slip off one button and onto the next. The price to pay is that gesture recognition is switched off in pianoMode.
(The DTMF dialer is also cooler in pianoMode, so changed that too.)
Also there's now 1000_hzand C_major examples, just so that not all examples are somewhat advanced bits of code. But Piano, like the DTMF_dialer, is still pretty small and quite readable for a stylish polyphonic piano:
/*
Polyphonic synthesizer. Lingering notes will continue to sound as new notes
are played. If you place one finger high on the screen and another low, you
can even play two notes at the same time. As you can see you can have many
synths going at the same time.
*/
#include <M5Core2.h>
#define WKW 40
#define WKH 240
#define BKW 30
#define BKH 160
#define WHITE_KEY {WHITE, NODRAW, BLACK}
#define BLACK_KEY {BLACK, NODRAW, NODRAW}
#define NUM_KEYS 14
float notes[NUM_KEYS] = { NOTE_F4 , NOTE_G4 , NOTE_A4 , NOTE_B4 , NOTE_C5,
NOTE_D5 , NOTE_E5 , NOTE_F5 , NOTE_Gb4, NOTE_Ab4,
NOTE_Bb4, NOTE_Db5, NOTE_Eb5, NOTE_Gb5 };
// (waveform, freq, attack, decay, sustain, release)
Synth synth[NUM_KEYS] = Synth(TRIANGLE, 0, 50, 300, 0.7, 1000);
Button f_( 0, 0, WKW, WKH, false, "f" , WHITE_KEY);
Button g_( 40, 0, WKW, WKH, false, "g" , WHITE_KEY);
Button A_( 80, 0, WKW, WKH, false, "A" , WHITE_KEY);
Button B_( 120, 0, WKW, WKH, false, "B" , WHITE_KEY);
Button C_( 160, 0, WKW, WKH, false, "C" , WHITE_KEY);
Button D_( 200, 0, WKW, WKH, false, "D" , WHITE_KEY);
Button E_( 240, 0, WKW, WKH, false, "E" , WHITE_KEY);
Button F_( 280, 0, WKW, WKH, false, "F" , WHITE_KEY);
Button gb( 25, 0, BKW, BKH, false, "gb", BLACK_KEY);
Button Ab( 65, 0, BKW, BKH, false, "Ab", BLACK_KEY);
Button Bb( 105, 0, BKW, BKH, false, "Bb", BLACK_KEY);
Button Db( 185, 0, BKW, BKH, false, "Db", BLACK_KEY);
Button Eb( 225, 0, BKW, BKH, false, "Eb", BLACK_KEY);
Button Gb( 305, 0, 15, BKH, false, "Gb", BLACK_KEY);
void setup() {
M5.begin();
M5.Buttons.draw();
// Prettier with top of keys as straight line
M5.Lcd.fillRect(0, 0, 320, 5, BLACK);
// Trick to make sure buttons do not draw over eachother anymore
M5.Buttons.drawFn = nullptr;
// So that you can swipe from one button to another
M5.Buttons.pianoMode = true;
// Set up syths with their notes
for (uint8_t n = 0; n < 14; n++) {
synth[n].freq = notes[n];
}
M5.Buttons.addHandler(pressKey , E_TOUCH);
M5.Buttons.addHandler(releaseKey, E_RELEASE);
}
void loop() {
M5.update();
}
void pressKey(Event& e) {
// instanceIndex() -4 because of background, BtnA, BtnB and BtnC.
uint8_t key = e.button->instanceIndex() - 4;
synth[key].start();
}
void releaseKey(Event& e) {
uint8_t key = e.button->instanceIndex() - 4;
synth[key].stop();
}
