grid

Transformations:

• for (int i=0; i<5; i++) -> for (let i=0; i<5; i++)
• push/popMatrix() -> push/pop()
• remove casts: (float) x -> x
• remove field modifiers private final -> ``
• remove float literal suffix 1.0f -> 1.0
• array initialization
  • literals {1, 2, 3, 4} -> [1, 2, 3, 4]
  • 1D: int[] values = new int[3] -> let values = new Array(3)
  • 2D: int[][] values = new int[3][4] -> let values = Array.from(new Array(3), () => new Array(4));
  • for/for-each loops work as expected with 2D arrays

This example also demonstrates that while, do/while, switch, and the ternary operator a ? b : c work unchanged.

Converted p5.js:

//
// grid
//
let n = 0x29a;
let dummy = [1, 2, 3, 4];
let dummy2 = new Array(5);
let numbers = [
    [1, 2, 3, 4],
    [5, 6, 7, 8],
    [9, 10, 11, 12],
    [13, 14, 15, 16],
];
let numbers2 = Array.from(new Array(2), () => new Array(3));
function setup() {
    createCanvas(400, 400);
    initializeArray(numbers2);
    printArray(numbers2);
    console.log("computeSum: " + computeSum(numbers2));
    console.log("computeSum2: " + computeSum2(numbers2));
}
function initializeArray(values) {
    let value = 1;
    for (let i = 0; i < values.length; i++)
        for (let j = 0; j < values[i].length; j++) values[i][j] = value++;
}
function printArray(values) {
    for (let row of values) {
        for (let value of row) console.log(value + " ");
        console.log();
    }
}
function drawFace(x, y) {
    fill(255);
    ellipse(x, y, 100, 100);
    fill(0);
    push();
    translate(-25, -10);
    ellipse(x, y, 20, 20);
    pop();
    push();
    translate(25, -10);
    ellipse(x, y, 20, 20);
    pop();
    ellipse(x, y + 25, 40, 20);
    let result = 0.0;
    return result;
}
function computeSum(numbers) {
    let total = 0;
    for (let row of numbers) for (let number of row) total += number;
    return total;
}
function computeSum2(numbers) {
    let total = 0;
    for (let i = 0; i < numbers.length; i++)
        for (let j = 0; j < numbers[i].length; j++) total += numbers[i][j];
    return total;
}
function draw() {
    background(0);
    textSize(20);
    textAlign(CENTER, CENTER);
    for (let i = 0; i < 4; i++) {
        for (let j = 0; j < 4; j++) {
            fill((i + j) % 2 == 1 ? 255 : 0);
            rect(j * 100, i * 100, 100, 100);
            fill((i + j) % 2 == 0 ? 255 : 0);
            text(numbers[i][j], j * 100 + 50, i * 100 + 50);
        }
    }
    let k = 0;
    while (k < 4) {
        drawFace(k * 100 + 50, k * 100 + 50);
        k++;
    }
    do {
        fill((255 * (k + 1)) / 4);
        rect(k * 100, (3 - k) * 100, 100, 100);
        switch (k) {
            case 0:
                fill(255, 0, 0);
                break;
            case 1:
                fill(0, 255, 0);
                break;
            case 2:
                fill(0, 0, 255);
                break;
            case 3:
                fill(255, 0, 255);
                break;
        }
        rect(k * 100 + 25, (3 - k) * 100 + 25, 50, 50);
    } while (k-- > 0);
    for (let i = 0; i < 4; i++)
        for (let j = 0; j < 4; j++) {
            fill(255, 0, 0);
            text(numbers[i][j], j * 100 + 50, i * 100 + 50);
        }
}

Original Processing:

//
// grid
//


private final int n = 0x29a;

int[] dummy = {1, 2, 3, 4};
int[] dummy2 = new int[5];

int[][] numbers = { {1, 2, 3, 4}, 
                   {5, 6, 7, 8}, 
                   {9, 10, 11, 12}, 
                   {13, 14, 15, 16} };

int[][] numbers2 = new int[2][3];

void setup()
{
    size(400, 400);

    initializeArray(numbers2);
    printArray(numbers2);
    println("computeSum: " + computeSum(numbers2));
    println("computeSum2: " + computeSum2(numbers2));
}

void initializeArray(int[][] values)
{
    int value = 1;
    for (int i=0; i<values.length; i++)
    for (int j=0; j<values[i].length; j++)
        values[i][j] = value++;
}


void printArray(int[][] values)
{
    for (int[] row : values)
    {
        for (int value : row)
            print(value + " ");
        println();
    }
}


float drawFace(int x, int y)
{
   fill(255);
   ellipse((float)x, y, 100, 100);
   fill(0);

   pushMatrix();
     translate(-25, -10);
     ellipse(x, y, 20, 20);
   popMatrix();
   
   pushMatrix();
     translate(25, -10);
     ellipse(x, y, 20, 20);
   popMatrix();

   ellipse(x, y+25, 40, 20);

   final float result = 0.0f;
   return result;
}


int computeSum(int[][] numbers)
{
    int total = 0;
    for (int[] row : numbers)
    for (int number : row)
        total += number;
    return total;
}

int computeSum2(int[][] numbers)
{
    int total = 0;
    for (int i=0; i<numbers.length; i++)
    for (int j=0; j<numbers[i].length; j++)
        total += numbers[i][j];
    return total;
}

void draw()
{
    background(0);
    textSize(20);
    textAlign(CENTER, CENTER);

  	for (int i=0; i<4; i++)
    {
        for (int j=0; j<4; j++)
        {
            fill( (i+j)%2==1 ? 255 : 0);
            rect(j*100, i*100, 100, 100);
            fill( (i+j)%2==0 ? 255 : 0);
            text(numbers[i][j], j*100+50, i*100+50);
        }
    }

    int k = 0;
    while (k < 4)
    {
        drawFace(k*100+50, k*100+50);
        k++;
    }

    do 
    {
        fill(255*(k+1)/4);
        rect(k*100, (3-k)*100, 100, 100);

        switch (k)
        {
            case 0:
              fill(255, 0, 0);
              break;
            case 1:
              fill(0, 255, 0);
              break;
            case 2:
              fill(0, 0, 255);
              break;
            case 3:
              fill(255, 0, 255);
              break;
        }
        rect(k*100+25, (3-k)*100+25, 50, 50);

    } while (k-- > 0);

  	for (int i=0; i<4; i++)
    for (int j=0; j<4; j++)
    {
        fill(255, 0, 0);
        text(numbers[i][j], j*100+50, i*100+50);
    }
}