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Snake vs Block Game to be run upon K64F.
Diff: Gamepad/Gamepad.cpp
- Revision:
- 0:4b15c2d4aa58
--- /dev/null Thu Jan 01 00:00:00 1970 +0000 +++ b/Gamepad/Gamepad.cpp Thu Mar 07 19:05:10 2019 +0000 @@ -0,0 +1,341 @@ +#include "Gamepad.h" + +#include "mbed.h" + +//////////// constructor/destructor //////////// +Gamepad::Gamepad() + : + _led1(new PwmOut(PTA1)), + _led2(new PwmOut(PTA2)), + _led3(new PwmOut(PTC2)), + _led4(new PwmOut(PTC3)), + _led5(new PwmOut(PTC4)), + _led6(new PwmOut(PTD3)), + + _button_A(new InterruptIn(PTB9)), + _button_B(new InterruptIn(PTD0)), + _button_X(new InterruptIn(PTC17)), + _button_Y(new InterruptIn(PTC12)), + _button_L(new InterruptIn(PTB18)), + _button_R(new InterruptIn(PTB3)), + _button_back(new InterruptIn(PTB19)), + _button_start(new InterruptIn(PTC5)), + _button_joystick(new InterruptIn(PTC16)), + + _vert(new AnalogIn(PTB10)), + _horiz(new AnalogIn(PTB11)), + + _buzzer(new PwmOut(PTC10)), + _pot(new AnalogIn(PTB2)), + + _timeout(new Timeout()), + + _event_state(0), + + _x0(0), + _y0(0) +{} + +Gamepad::~Gamepad() +{ + delete _led1,_led2,_led3,_led4,_led5,_led6; + delete _button_A,_button_B,_button_joystick,_vert,_horiz; + delete _button_X,_button_Y,_button_back,_button_start; + delete _button_L,_button_R, _buzzer, _pot, _timeout; +} + +///////////////// public methods ///////////////// + +void Gamepad::init() +{ + leds_off(); + init_buttons(); + + // read centred values of joystick + _x0 = _horiz->read(); + _y0 = _vert->read(); + + // clear all flags + _event_state = 0; +} + +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 vlaid 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_pot() const +{ + return _pot->read(); +} + +void Gamepad::tone(float frequency, float duration) +{ + _buzzer->period(1.0f/frequency); + _buzzer->write(0.5); // 50% duty cycle - square wave + _timeout->attach(callback(this, &Gamepad::tone_off), duration ); +} + +bool Gamepad::check_event(GamepadEvent const id) +{ + // Check whether event flag is set + if (_event_state[id]) { + _event_state.reset(id); // clear flag + return true; + } else { + return false; + } +} + +// 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; +} + +///////////////////// private methods //////////////////////// + +void Gamepad::tone_off() +{ + // called after timeout + _buzzer->write(0.0); +} + +void Gamepad::init_buttons() +{ + // turn on pull-downs as other side of button is connected to 3V3 + // button is 0 when not pressed and 1 when pressed + _button_A->mode(PullDown); + _button_B->mode(PullDown); + _button_X->mode(PullDown); + _button_Y->mode(PullDown); + _button_back->mode(PullDown); + _button_start->mode(PullDown); + _button_L->mode(PullDown); + _button_R->mode(PullDown); + _button_joystick->mode(PullDown); + // therefore setup rising edge interrupts + _button_A->rise(callback(this,&Gamepad::a_isr)); + _button_B->rise(callback(this,&Gamepad::b_isr)); + _button_X->rise(callback(this,&Gamepad::x_isr)); + _button_Y->rise(callback(this,&Gamepad::y_isr)); + _button_L->rise(callback(this,&Gamepad::l_isr)); + _button_R->rise(callback(this,&Gamepad::r_isr)); + _button_start->rise(callback(this,&Gamepad::start_isr)); + _button_back->rise(callback(this,&Gamepad::back_isr)); + _button_joystick->rise(callback(this,&Gamepad::joy_isr)); +} + +// button interrupts ISRs +// Each of these simply sets the appropriate event bit in the _event_state +// variable +void Gamepad::a_isr() +{ + _event_state.set(A_PRESSED); +} +void Gamepad::b_isr() +{ + _event_state.set(B_PRESSED); +} +void Gamepad::x_isr() +{ + _event_state.set(X_PRESSED); +} +void Gamepad::y_isr() +{ + _event_state.set(Y_PRESSED); +} +void Gamepad::l_isr() +{ + _event_state.set(L_PRESSED); +} +void Gamepad::r_isr() +{ + _event_state.set(R_PRESSED); +} +void Gamepad::back_isr() +{ + _event_state.set(BACK_PRESSED); +} +void Gamepad::start_isr() +{ + _event_state.set(START_PRESSED); +} +void Gamepad::joy_isr() +{ + _event_state.set(JOY_PRESSED); +} + +// 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 x value here is inverted to ensure the positive x is to the + // right. This is simply due to how the potentiometer on the joystick + // I was using was connected up. It could have been corrected in hardware + // by swapping the power supply pins. Instead it is done in software so may + // need to be changed depending on your wiring setup + + 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; +} \ No newline at end of file