Craig Evans
Pong for Gamepad2
Edit.
Diff: Gamepad2/Gamepad.cpp
- Revision:
- 0:7423345f87c5
--- /dev/null Thu Jan 01 00:00:00 1970 +0000
+++ b/Gamepad2/Gamepad.cpp Fri Jan 31 12:32:38 2020 +0000
@@ -0,0 +1,464 @@
+#include "Gamepad.h"
+
+#include "mbed.h"
+
+//////////// constructor/destructor ////////////
+Gamepad::Gamepad()
+ :
+ _led1(new PwmOut(PTA2)),
+ _led2(new PwmOut(PTC2)),
+ _led3(new PwmOut(PTC3)),
+ _led4(new PwmOut(PTA1)),
+ _led5(new PwmOut(PTC10)),
+ _led6(new PwmOut(PTC11)),
+
+ _button_A(new InterruptIn(PTC7)),
+ _button_B(new InterruptIn(PTC9)),
+ _button_X(new InterruptIn(PTC5)),
+ _button_Y(new InterruptIn(PTC0)),
+ _button_start(new InterruptIn(PTC8)),
+
+ _vert(new AnalogIn(PTB11)),
+ _horiz(new AnalogIn(PTB10)),
+
+ _pot1(new AnalogIn(PTB2)),
+ _pot2(new AnalogIn(PTB3)),
+
+ dac(new AnalogOut(DAC0_OUT)),
+ ticker(new Ticker),
+ timeout(new Timeout),
+ note_timeout(new Timeout),
+
+ _x0(0),
+ _y0(0)
+{}
+
+
+///////////////// public methods /////////////////
+
+void Gamepad::init()
+{
+ leds_off();
+
+ // read centred values of joystick
+ _x0 = _horiz->read();
+ _y0 = _vert->read();
+
+ // Set all buttons to PullUp
+ _button_A->mode(PullUp);
+ _button_B->mode(PullUp);
+ _button_X->mode(PullUp);
+ _button_Y->mode(PullUp);
+ _button_start->mode(PullUp);
+
+ // Set up interrupts for the fall of buttons
+ _button_A->fall(callback(this,&Gamepad::A_fall_interrupt));
+ _button_B->fall(callback(this,&Gamepad::B_fall_interrupt));
+ _button_X->fall(callback(this,&Gamepad::X_fall_interrupt));
+ _button_Y->fall(callback(this,&Gamepad::Y_fall_interrupt));
+ _button_start->fall(callback(this,&Gamepad::start_fall_interrupt));
+
+ // initalise button flags
+ reset_buttons();
+
+ // number of samples
+ _n = 16;
+ _sample_array = new float[_n];
+
+ // create sample array for one period between 0.0 and 1.0
+ for (int i = 0; i < _n ; i++) {
+ _sample_array[i] = 0.5f + 0.5f*sin(i*2*PI/_n);
+ //printf("y[%i] = %f\n",i,_sample_array[i]);
+ }
+
+}
+
+void Gamepad::leds_off()
+{
+ leds(0.0);
+}
+
+void Gamepad::leds_on()
+{
+ leds(1.0);
+}
+
+void Gamepad::leds(float val) const
+{
+ if (val < 0.0f) {
+ val = 0.0f;
+ }
+ if (val > 1.0f) {
+ val = 1.0f;
+ }
+
+ // leds are active-low, so subtract from 1.0
+ // 0.0 corresponds to fully-off, 1.0 to fully-on
+ val = 1.0f - val;
+
+ _led1->write(val);
+ _led2->write(val);
+ _led3->write(val);
+ _led4->write(val);
+ _led5->write(val);
+ _led6->write(val);
+}
+
+void Gamepad::led(int n,float val) const
+{
+ // ensure they are within valid range
+ if (val < 0.0f) {
+ val = 0.0f;
+ }
+ if (val > 1.0f) {
+ val = 1.0f;
+ }
+
+ switch (n) {
+
+ // check for valid LED number and set value
+
+ case 1:
+ _led1->write(1.0f-val); // active-low so subtract from 1
+ break;
+ case 2:
+ _led2->write(1.0f-val); // active-low so subtract from 1
+ break;
+ case 3:
+ _led3->write(1.0f-val); // active-low so subtract from 1
+ break;
+ case 4:
+ _led4->write(1.0f-val); // active-low so subtract from 1
+ break;
+ case 5:
+ _led5->write(1.0f-val); // active-low so subtract from 1
+ break;
+ case 6:
+ _led6->write(1.0f-val); // active-low so subtract from 1
+ break;
+
+ }
+}
+
+float Gamepad::read_pot1() const
+{
+ return _pot1->read();
+}
+
+float Gamepad::read_pot2() const
+{
+ return _pot2->read();
+}
+
+
+// this method gets the magnitude of the joystick movement
+float Gamepad::get_mag()
+{
+ Polar p = get_polar();
+ return p.mag;
+}
+
+// this method gets the angle of joystick movement (0 to 360, 0 North)
+float Gamepad::get_angle()
+{
+ Polar p = get_polar();
+ return p.angle;
+}
+
+Direction Gamepad::get_direction()
+{
+ float angle = get_angle(); // 0 to 360, -1 for centred
+
+ Direction d;
+ // partition 360 into segments and check which segment the angle is in
+ if (angle < 0.0f) {
+ d = CENTRE; // check for -1.0 angle
+ } else if (angle < 22.5f) { // then keep going in 45 degree increments
+ d = N;
+ } else if (angle < 67.5f) {
+ d = NE;
+ } else if (angle < 112.5f) {
+ d = E;
+ } else if (angle < 157.5f) {
+ d = SE;
+ } else if (angle < 202.5f) {
+ d = S;
+ } else if (angle < 247.5f) {
+ d = SW;
+ } else if (angle < 292.5f) {
+ d = W;
+ } else if (angle < 337.5f) {
+ d = NW;
+ } else {
+ d = N;
+ }
+
+ return d;
+}
+
+void Gamepad::reset_buttons()
+{
+ A_fall = B_fall = X_fall = Y_fall = start_fall = false;
+}
+
+bool Gamepad::A_pressed()
+{
+ if (A_fall) {
+ A_fall = false;
+ return true;
+ } else {
+ return false;
+ }
+}
+
+bool Gamepad::B_pressed()
+{
+ if (B_fall) {
+ B_fall = false;
+ return true;
+ } else {
+ return false;
+ }
+}
+
+bool Gamepad::X_pressed()
+{
+ if (X_fall) {
+ X_fall = false;
+ return true;
+ } else {
+ return false;
+ }
+}
+
+bool Gamepad::Y_pressed()
+{
+ if (Y_fall) {
+ Y_fall = false;
+ return true;
+ } else {
+ return false;
+ }
+}
+
+bool Gamepad::start_pressed()
+{
+ if (start_fall) {
+ start_fall = false;
+ return true;
+ } else {
+ return false;
+ }
+}
+
+bool Gamepad::A_held()
+{
+ // Buttons are configured as PullUp hence the not
+ return !_button_A->read();
+}
+
+bool Gamepad::B_held()
+{
+ return !_button_B->read();
+}
+
+bool Gamepad::X_held()
+{
+ return !_button_X->read();
+}
+
+bool Gamepad::Y_held()
+{
+ return !_button_Y->read();
+}
+
+bool Gamepad::start_held()
+{
+ return !_button_start->read();
+}
+
+///////////////////// private methods ////////////////////////
+
+// get raw joystick coordinate in range -1 to 1
+// Direction (x,y)
+// North (0,1)
+// East (1,0)
+// South (0,-1)
+// West (-1,0)
+Vector2D Gamepad::get_coord()
+{
+ // read() returns value in range 0.0 to 1.0 so is scaled and centre value
+ // substracted to get values in the range -1.0 to 1.0
+ float x = 2.0f*( _horiz->read() - _x0 );
+ float y = 2.0f*( _vert->read() - _y0 );
+
+ // Note: the y value here is inverted to ensure the positive y is up
+
+ Vector2D coord = {x,-y};
+ return coord;
+}
+
+// This maps the raw x,y coord onto a circular grid.
+// See: http://mathproofs.blogspot.co.uk/2005/07/mapping-square-to-circle.html
+Vector2D Gamepad::get_mapped_coord()
+{
+ Vector2D coord = get_coord();
+
+ // do the transformation
+ float x = coord.x*sqrt(1.0f-pow(coord.y,2.0f)/2.0f);
+ float y = coord.y*sqrt(1.0f-pow(coord.x,2.0f)/2.0f);
+
+ Vector2D mapped_coord = {x,y};
+ return mapped_coord;
+}
+
+// this function converts the mapped coordinates into polar form
+Polar Gamepad::get_polar()
+{
+ // get the mapped coordinate
+ Vector2D coord = get_mapped_coord();
+
+ // at this point, 0 degrees (i.e. x-axis) will be defined to the East.
+ // We want 0 degrees to correspond to North and increase clockwise to 359
+ // like a compass heading, so we need to swap the axis and invert y
+ float x = coord.y;
+ float y = coord.x;
+
+ float mag = sqrt(x*x+y*y); // pythagoras
+ float angle = RAD2DEG*atan2(y,x);
+ // angle will be in range -180 to 180, so add 360 to negative angles to
+ // move to 0 to 360 range
+ if (angle < 0.0f) {
+ angle+=360.0f;
+ }
+
+ // the noise on the ADC causes the values of x and y to fluctuate slightly
+ // around the centred values. This causes the random angle values to get
+ // calculated when the joystick is centred and untouched. This is also when
+ // the magnitude is very small, so we can check for a small magnitude and then
+ // set the angle to -1. This will inform us when the angle is invalid and the
+ // joystick is centred
+
+ if (mag < TOL) {
+ mag = 0.0f;
+ angle = -1.0f;
+ }
+
+ Polar p = {mag,angle};
+ return p;
+}
+
+// ISRs for buttons
+void Gamepad::A_fall_interrupt()
+{
+ A_fall = true;
+}
+void Gamepad::B_fall_interrupt()
+{
+ B_fall = true;
+}
+void Gamepad::X_fall_interrupt()
+{
+ X_fall = true;
+}
+void Gamepad::Y_fall_interrupt()
+{
+ Y_fall = true;
+}
+void Gamepad::start_fall_interrupt()
+{
+ start_fall = true;
+}
+
+void Gamepad::set_bpm(float bpm)
+{
+ _bpm = bpm;
+}
+
+void Gamepad::tone(float frequency,float duration)
+{
+ // calculate time step between samples
+ float dt = 1.0f/(frequency*_n);
+ // start from beginning of LUT
+ _sample = 0;
+
+ // setup ticker and timeout to stop ticker
+
+ // the ticker repeats every dt to plat each sample in turn
+ ticker->attach(callback(this, &Gamepad::ticker_isr), dt);
+ // the timeout stops the ticker after the required duration
+ timeout->attach(callback(this, &Gamepad::timeout_isr), duration );
+}
+
+void Gamepad::play_melody(int length,const int *notes,const int *durations,float bpm,bool repeat)
+{
+ // copy arguments to member variables
+ _bpm = bpm;
+ _notes = notes; // pointer for array
+ _durations = durations; // pointer for array
+ _melody_length = length;
+ _repeat = repeat;
+
+ _note = 0; // start from first note
+
+ play_next_note(); // play the next note in the melody
+}
+
+void Gamepad::write_dac(float val)
+{
+ if (val < 0.0f) {
+ val = 0.0f;
+ } else if (val > 1.0f) {
+ val = 1.0f;
+ }
+ dac->write(val);
+}
+
+
+void Gamepad::play_next_note()
+{
+ // _note is the note index to play
+
+ // calculate the duration and frequency of the note
+ float duration = 60.0f/(_bpm*_durations[_note]);
+ float frequency = float(_notes[_note]);
+ //printf("[%i] f = %f d = %f\n",_note,frequency,duration);
+
+ // check if the note is not a space and if not then play the note
+ if (frequency > 0) {
+ tone(frequency,duration);
+ }
+
+ // the timeout goes to the next note in the melody
+ // double the duration to leave a bit of a gap in between notes to be better
+ // able to distinguish them
+ note_timeout->attach(callback(this, &Gamepad::note_timeout_isr), duration*2.0f );
+}
+
+// called when the next note needs playing
+void Gamepad::note_timeout_isr()
+{
+ _note++; // go onto next note
+
+ // if in repeat mode then reset the note counter when get to end of melody
+ if (_repeat && _note == _melody_length) {
+ _note=0;
+ }
+
+ // check if note is within the melody
+ if (_note < _melody_length) {
+ play_next_note();
+ }
+}
+
+void Gamepad::ticker_isr()
+{
+ dac->write(_sample_array[_sample%_n]); // use modulo to get index to play
+ _sample++; // increment the sample ready for next time
+}
+
+void Gamepad::timeout_isr()
+{
+ // stops the ticker to end the note
+ ticker->detach();
+}