Can someone/anyone direct me to any additional beginner-coder-friendly tutorial(s) on ArrayLists? I am watching the Coding Train tutorials in The Nature of Code playlist. And the explanations ARE indeed clear. I have also read the processing.org reference. And, surfed through java tutorials on yo…

Remark sub = new ArrayList <SubGrid>(); // this deletes the whole thing Remark without background (255); at start of draw() you see the accumulated results of all drawings. You can’t really see what the last mousePressed did! Remark I think this doesn’t do what you want: rect (x, y, …

In mousePressed () [image] debxyz: PVector pv = new PVector (x, y); Please try to derive x and y from a previous rectangle and modify it like x = resizeableGrid.get(i).x + tile/2; y = resizeableGrid.get(i).y; PVector pv = new PVector (x, y); With i from the for loop that you already have …

Or use the short for-loop form for (PVector pv1 : points) then you don’t need .get()

Also in this scenario when you want to split up a rectangle into two parts, it might be worthwhile to consider making a class Rectangle. Then you can store its size and in the event of splitting reduce its size by half. And you can store a different color.

[image] Chrisir: Please try to derive x and y from a previous rectangle and modify it like x = resizeableGrid.get(i).x + tile/2; I will try this. Thank you! :slight_smile:

[image] Chrisir: it might be worthwhile to consider making a class Rectangle. Yes, I will likely end up doing that. Though, at this point, since I don’t yet have a good understanding of what is happening with the syntax OR what is happening under the hood in terms of add, get I thought it m…

[image] debxyz: Can someone/anyone direct me to any additional beginner-coder-friendly tutorial(s) on ArrayLists ? Shameless self-promotion: [image] ArrayLists Learn how to use ArrayLists in Processing.

here is a Sketch that adds cells as discussed (almost) Chrisir ArrayList<PVector>resizeableGrid = new ArrayList(); float tile; void setup() { size (600, 600); tile = width/3; for (float x = 0; x <= width; x+=tile) { for (float y = 0; y <= height; y+=tile) { PVector pv = new PVe…

[image] debxyz: And then move on to creating separate object classes. ArrayList is really like a more flexible array. I think you can move on to ArrayList of a class now.

here is a non-running part from a much bigger Sketch that shows how to show bullets (it’s from a player who shoots) and how to remove the bullets (in a backward for-loop) that are dead (because they left the screen or hit something, then the variable dead in the class Explosion is set to true). Th…

Somehow I missed your site in the returned results when I googled ArrayLists previously… Thank you for this link!! It definitely adds to my understanding. :nerd_face:

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Processing Beginners

Kevin May 23, 2020, 7:38pm 18

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