P5 code into Java + help in understanding (artwork)

p5.js Coding Questions
11

I suspect your main issue is understanding how to convert JS arrays to Java 1s.

As an example, take a look at this Java flavor sketch: “Conglomerate of Points (Java)”

That sketch declares & initializes 2 arrays of datatype PVector[]:

final PVector[] points = new PVector[QTY], tPoints = new PVector[QTY];

And then fill those up using a for ( ; ; ) loop:

  for (int i = 0; i < QTY; ++i) {
    points[i]  = new PVector(random(width), random(height));
    tPoints[i] = new PVector(random(width), random(height));
  }

Now let’s take a look at its corresponding p5js flavor conversion: “Conglomerate of Points (p5js)”
http://p5js.SketchPad.cc/sp/pad/view/ro.$V3VWYDTmRb/latest

And the syntax being used for declaring & initializing those 2 arrays in JS:

const points = Array(QTY).fill(), tPoints = Array(QTY).fill();

Usually in JS we create arrays using the [] syntax, which is empty by default.

But JS also offers the Array constructor, where we can specify its initial length:

Method fill() merely solidifies the array by filling it up w/ an optional specified value:

And its corresponding for ( ; ; ) loop is very similar to the Java version:

  for (let i = 0; i < QTY; ++i) {
    points[i]  = createVector(random(width), random(height));
    tPoints[i] = createVector(random(width), random(height));
  }

For a more complete tutorial about Java arrays please read this:

2 Likes