This example is for Processing 3+. If you have a previous version, use the examples included with your software. If you see any errors or have suggestions, please let us know.

Array 2D.

Demonstrates the syntax for creating a two-dimensional (2D) array. Values in a 2D array are accessed through two index values. 2D arrays are useful for storing images. In this example, each dot is colored in relation to its distance from the center of the image.

float[][] distances;
float maxDistance;
int spacer;

void setup() {
  size(640, 360);
  maxDistance = dist(width/2, height/2, width, height);
  distances = new float[width][height];
  for (int y = 0; y < height; y++) {
    for (int x = 0; x < width; x++) {
      float distance = dist(width/2, height/2, x, y);
      distances[x][y] = distance/maxDistance * 255;
  spacer = 10;
  noLoop();  // Run once and stop

void draw() {
  // This embedded loop skips over values in the arrays based on
  // the spacer variable, so there are more values in the array
  // than are drawn here. Change the value of the spacer variable
  // to change the density of the points
  for (int y = 0; y < height; y += spacer) {
    for (int x = 0; x < width; x += spacer) {
      point(x + spacer/2, y + spacer/2);