File content as of revision 20:f634b1060981:

/**
@file main.cpp

@brief Program implementation of Snake Game

*/
 
#include "mbed.h"
#include "main.h"
#include "N5110.h"
#include "beep.h"
#include "SDFileSystem.h"
#include "Joystick.h"
#include "fsmMenu.h"
 
//         VCC,    SCE,   RST,   D/C,   MOSI,  SCLK,   LED
N5110 lcd (PTD3, PTA0 , PTC4 , PTD0 , PTD2 , PTD1 , PTC3);
// Can also power (VCC) directly from VOUT (3.3 V) -
// Can give better performance due to current limitation from GPIO pin

// Connections to SD card holder on K64F (SPI interface)
SDFileSystem sd(PTE3, PTE1, PTE2, PTE4, "sd"); // MOSI, MISO, SCK, CS
 
/// Serial for debug
Serial serial(USBTX,USBRX);
Ticker pollJoystick;
Ticker gameTicker;


 
FILE *fp; // this is our file pointer

void timer_isr();
void rb_isr();
void lb_isr();

int main()
{    
    calibrateJoystick();  // get centred values of joystick
    pollJoystick.attach(&updateJoystick,0.5/10.0);  // read joystick 20 times per second
    
    srand(time(NULL));
    
    greenLed = 1;
    redLed = 0;
    lcd.init();
    snakeIntro();
    gamePlaying = false;
    button.rise(&buttonISR);
    gameTicker.attach(&timer_isr,0.1);
    RB.mode(PullDown);
    LB.mode(PullDown);
    RB.rise(&rb_isr);
    LB.rise(&lb_isr);
    
    
    mainMenu();
 
}
 
void mainGame() {
    
    if(gameType == classicMode) {
        hardWall();
        i = 41;
        j = 23;
    }
    else if(gameType == infiniteMode) {
        wrapAround();
        i = 40;
        j = 22;
    }
    else {
        specialMap();
        i = 13;
        j = 5;
    }
    generateFood();
    initSnakeTail();
    snakeTailLength = 3;
    score = 0;
    fruitValue = 10; 
    pauseCount = 0;   // init everything
    
   while(gamePlaying == true) {
        
        lcd.setBrightness(1-pot); // turn pot right for brightness
        
        if (buttonFlag ==1) {
            buttonFlag = 0;  
            if (pauseCount < 3) {
                gamePaused();
            }
            buttonFlag = 0;
        }
        buttonFlag = 0;
        
        if(game_timer_flag) {
            game_timer_flag = 0;
            gameLogic();
        }
        if (printFlag) {  // if flag set, clear flag and print joystick values to serial port
            printFlag = 0;
            moveSnake();
            } 
            sleep(); // put the MCU to sleep until an interrupt wakes it up
    }
}  

void mainMenu() {
    
        while(1) {
          
        lcd.printString("Classic",0,1);
        lcd.printString("Infinite",0,3);
        lcd.printString("Hard Map",0,5); 
        
        if (rb_flag == 1) {
            rb_flag = 0;
            gamePlaying = true;
            mainGame();  
        }
        
    // check if flag i.e. interrupt has occured
        if (printFlag ==1) {
            printFlag = 0;  // if it has, clear the flag
 
            // swap direction when button has been pressed
            // (could just use ! but want this to be explicit to aid understanding)
            if (joystick.direction == CENTRE) {
                serial.printf(" CENTRE\n");
                menuDirection = menuSTOP;
                }
            else if (joystick.direction == UP) {
                serial.printf(" UP\n");
                menuDirection = menuUP;
                buzzer.beep(2000,0.2);    
            }
            else if (joystick.direction == DOWN) {
                serial.printf(" DOWN\n");
                menuDirection = menuDOWN;
                buzzer.beep(2000,0.2);  
            }
        }
    
    
        menuFSM();
    
    
        wait(0.2); // small delay
        if (state ==0) {
        lcd.clear();   
        lcd.printString("*",70,1);   
        gameType = classicMode; 
        }
        else if (state ==1) {
        lcd.clear();
        lcd.printString("*",70,3);
        gameType = infiniteMode;   
        }
        else if (state ==2) {
        lcd.clear();
        lcd.printString("*",70,5);
        gameType = hardMode;  
        }  
           
    } 
    
}    

void generateFood()
{
    if (gameType == classicMode || gameType == hardMode) {
        while (randomXoddEven ==0 || randomYoddEven ==0 || lcd.getPixel(randomX,randomY) >= 1) { // do while x or y is even or pixel is on
            
            randomX =  rand() % 83 + 1;     // randomX in the range 1 to 83
            randomY =  rand() % 47 + 1;     // randomY in the range 1 to 47     
            randomXoddEven = randomX%2; // find out whether odd or even
            randomYoddEven = randomY%2;  
            }
            
            lcd.drawRect(randomX,randomY,1,1,1);
    }
    
    else {
        while (randomXoddEven ==1 || randomYoddEven ==1 || lcd.getPixel(randomX,randomY) >= 1) { // do while x or y is even or pixel is on
            
            randomX =  rand() % 83 + 1;     // randomX in the range 1 to 83
            randomY =  rand() % 47 + 1;     // randomY in the range 1 to 47     
            randomXoddEven = randomX%2; // find out whether odd or even
            randomYoddEven = randomY%2;  
            }
            
            lcd.drawRect(randomX,randomY,1,1,1);
    }

}

void newFruitXY() // new fruit coordinate values are given before it is passed to the generateFood function
{
                 
        randomX =  rand() % 83 + 1;     // randomX in the range 1 to 81
        randomY =  rand() % 47 + 1;     // randomY in the range 1 to 47
        randomXoddEven = randomX%2; // find out whether odd or even
        randomYoddEven = randomY%2;
 
}
 
void moveSnake() {
    
    if (joystick.direction == LEFT) { 
                if (currentDirection != right) { // change the currentDirection according to joystick input, providing
                currentDirection = left;         // it's not the opposite direction to the current direction
                }
                }
    else if (joystick.direction == RIGHT) {
                if (currentDirection != left) { // change the currentDirection according to joystick input, providing
                currentDirection = right;       // it's not the opposite direction to the current direction
                }
                }
    else if (joystick.direction == UP) {
                if (currentDirection != down) { // change the currentDirection according to joystick input, providing
                currentDirection = up;          // it's not the opposite direction to the current direction
                }
                }
    else if (joystick.direction == DOWN) {
                if (currentDirection != up) { // change the currentDirection according to joystick input, providing
                currentDirection = down;      // it's not the opposite direction to the current direction
                }
                }
}
 
void gameLogic() {

            lcd.clear();
            greenLed = 1;
            
            
            prev_i = snakeTailX[0];
            prev_j = snakeTailY[0]; 
            snakeTailX[0] = i; 
            snakeTailY[0] = j;

            for (int a=1; a<snakeTailLength; a++) { // loops through snakeTail array and assigns previous seg's coordinates to current one
                prev2_i = snakeTailX[a]; 
                prev2_j = snakeTailY[a];
                snakeTailX[a] = prev_i;
                snakeTailY[a] = prev_j;
                prev_i = prev2_i; 
                prev_j = prev2_j;
             }
            
            
            if (currentDirection == left) { // shift snake head coordinates according to current direction
            i -= 2; } // move left
            else if (currentDirection == right) {
            i += 2; } // move right
            else if (currentDirection == up) {
            j -= 2; } // move up
            else if (currentDirection == down) {
            j += 2; } // move down
            
            
            lcd.drawRect(i,j,1,1,1); // snake head
            for (int b=0; b<snakeTailLength; b++) {
                 lcd.drawRect(snakeTailX[b],snakeTailY[b],1,1,1);
                 }    
         
            lcd.refresh();

            lcd.drawRect(randomX,randomY,1,1,1); // food
            
            if (gameType == classicMode) { // map types
                hardWall();
            }
            else if (gameType == infiniteMode) {
                wrapAround();
            }
            else {
                specialMap();
            }
            
            if (i == randomX && j == randomY) { // if fruit is eaten
                greenLed = 0;
                buzzer.beep(2000,0.2); 
                scoreCalculation();
                snakeTailLength++;
                newFruitXY();
                generateFood();
                }
                
            if (snakeTailLength > 4) { // if snake eats itself
            for (int q=1; q<snakeTailLength; q++) {
                if (snakeTailX[q] == i && snakeTailY[q] == j) {
                    gameOver();
                    }
                }
            }

}
 
 
void hardWall() {

    lcd.drawRect(0,0,83,47,0);
    lcd.refresh();
    if (i == 0 || i+1 == 0 ||
        i == 83 || i+1 == 83 || // if any of the 4 pixels within the snake head touch the border
        j == 0 || j+1 == 0 ||
        j == 47 || j+1 == 47)
        {
            i = 41;
            j = 23;
            gameOver(); 
        }
   
}

void gameOver() {
    
    redLed = 1;
    if(score > top_score) {
             ////////////////////// Simple writing example //////////////////////////
    
        // open file for writing ('w') - creates file if it doesn't exist and overwrites
        // if it does. If you wish to add a score onto a list, then you can
        // append instead 'a'. This will open the file if it exists and start
        // writing at the end. It will create the file if it doesn't exist.
        fp = fopen("/sd/topscore.txt", "w");
        int top_score = score;
    
        if (fp == NULL) {  // if it can't open the file then print error message
            serial.printf("Error! Unable to open file!\n");
        } else {  // opened file so can write
            serial.printf("Writing to file....");
            fprintf(fp, "%d",top_score); // ensure data type matches
            serial.printf("Done.\n");
            fclose(fp);  // ensure you close the file after writing
        }
    }
     gamePlaying = false;
        lcd.clear();
        buzzer.beep(294,0.5);
        wait(0.5);
        lcd.printString("Game Over",15,0); // width(6) * n(9) = 54, 84-54 = 30, 30/2 = 15
        buzzer.beep(277,0.5);
        wait(0.5);
        
        char buffer[14];
        int length = sprintf(buffer,"Score:%i",score); // display score of round
        if (length <= 14) { // if string will fit on display
            lcd.printString(buffer,0,1); }           // display on screen
        buzzer.beep(262,2);
        wait(0.5);
         ////////////////////// Simple reading example //////////////////////////

    // now open file for reading
    fp = fopen("/sd/topscore.txt", "r");
  //  int stored_top_score = -1;  // -1 to demonstrate it has changed after reading

    if (fp == NULL) {  // if it can't open the file then print error message
        serial.printf("Error! Unable to open file!\n");
    } else {  // opened file so can write
        fscanf(fp, "%d",&top_score); // ensure data type matches - note address operator (&)
        serial.printf("Read %d from file.\n",top_score);
        char buffer[14];
        int length = sprintf(buffer,"HI Score:%i",top_score); // display score of round
        if (length <= 14) { // if string will fit on display
            lcd.printString(buffer,0,2); }           // display on screen
        fclose(fp);  // ensure you close the file after reading
    }
        wait(0.5);
        redLed = 0;
        
        lcd.printString("RB - Restart",0,4);
        wait(0.5);
        lcd.printString("LB - Menu",0,5);
       
       while(1) {
            if (rb_flag == 1) {
                rb_flag = 0;
                gamePlaying = true;
                mainGame();
            }
            rb_flag = 0;
            if (lb_flag == 1) {
                lb_flag = 0;
                gamePlaying = false;
                mainMenu();
            }
            sleep();
        }
}


void specialMap() {

    lcd.drawRect(0,0,83,47,0);
    lcd.drawRect(15,9,1,31,1);
    lcd.drawRect(33,9,1,31,1);
    lcd.drawRect(49,9,1,31,1);
    lcd.refresh();
    if (i == 0 || i+1 == 0 ||
        i == 83 || i+1 == 83 || // if any of the 4 pixels within the snake head touch the border
        j == 0 || j+1 == 0 ||
        j == 47 || j+1 == 47)
        {
            i = 13;
            j = 5;
            gameOver(); 
        }
      
}

void wrapAround() {

    if (i == -2) {
        i = 82;
        }
    if (i == 84) {
        i = 0;
        }
    if (j == -2) {
        j = 46;
        }
    if (j == 48) {
        j = 0;
        }    
    
}


void scoreCalculation() {
 
    score += fruitValue; // each time fruit is eaten score is calculated and fruit value will increase by 1
    
    fruitValue++;
    
    //serial.printf("score = %i\n",score);
    //serial.printf("fruitValue = %i\n\n",fruitValue);
       
}

void initSnakeTail() {
    
    if (gameType == classicMode) {
    prev_i = 39;
    prev_j = 23;
    prev2_i = 37;
    prev2_j = 23;
    }
    else if (gameType == infiniteMode) {
    prev_i = 38;
    prev_j = 22;
    prev2_i = 36;
    prev2_j = 22;
    }
    else {
    prev_i = 11;
    prev_j = 5;
    prev2_i = 9;
    prev2_j = 5;
    }
    
    snakeTailX[0] = i;
    snakeTailY[0] = j;
    snakeTailX[1] = prev_i;
    snakeTailY[1] = prev_j;
    snakeTailX[2] = prev2_i;
    snakeTailY[2] = prev2_j;
     
     lcd.drawRect(i,j,1,1,1); // snake head
                for (int b=0; b<snakeTailLength; b++) {
                     lcd.drawRect(snakeTailX[b],snakeTailY[b],1,1,1);
                     }
     currentDirection = right;                   
    
} 

void snakeIntro() {
  
  for(int i=0; i<WIDTH; i++) {
        for(int j=0; j<HEIGHT; j++) {
            lcd.setPixel(i,j);
        }
    }
    for (int q=0; q<WIDTH/2; q++) {
    lcd.drawCircle(WIDTH/2,HEIGHT/2,q,2);
    wait_ms(2);
    }  // x,y,radius,white fill
    
    lcd.printString("Snake",27,0);
    buzzer.beep(2000,0.5);   
    wait(0.5);
    lcd.printString("by",36,2);
    buzzer.beep(1000,0.5);
    wait(0.5);
    lcd.printString("Meurig",24,3);
    buzzer.beep(500,0.5);
    wait(0.5);
    lcd.printString("Phillips",18,4);
    buzzer.beep(250,2);
    wait(2);
    
    lcd.clear();  
    
 }
 
 void gamePaused() {
     
        wait_ms(100);
        pauseCount++;
        lcd.clear();
        char buffer[14];
        int length = sprintf(buffer,"%i left",3-pauseCount); // number of pauses left
        if (length <= 14) { // if string will fit on display
            lcd.printString(buffer,24,3); }           // display on screen
            
        lcd.printString("Paused 5",18,1);
        wait(1);
        lcd.printString("Paused 4",18,1);
        wait(1);
        lcd.printString("Paused 3",18,1);
        wait(1);
        lcd.printString("Paused 2",18,1);
        wait(1);
        lcd.printString("Paused 1",18,1);
        wait(1);
              
}

void timer_isr()
{
game_timer_flag = 1;   
}

void rb_isr()
{
rb_flag = 1;   
}

void lb_isr()
{
lb_flag = 1;   
}