I need a review for the Coursera course, Part II module 5 (Jack application)

[yokes_in_flight]

Hi all — for those doing the Coursera version, I need a few more reviews for module 5 (Part II), where you have to build a Jack application.

I've implemented the Boids algorithm in Jack! It was challenging (no floating-point algorithms and only 16 bits of RAM), but rewarding!

I'll appreciate a review: https://www.coursera.org/learn/nand2tetris2/peer/kyLgr/project-9/review/b8aqHWv3EfC3XQ7ON9BbFw

And when the time comes when you need reviews, let me know, and I'll be happy to help!

[dolomiti7]

Looks really nice. Just gave you a review on coursera. There is one minor bug which is ignored in the web-ide internal OS representation:
In Boid.draw and Boid.clear you call:

do Screen.drawRectangle(positionX, positionY, positionX + size, positionY + size);

This creates a rectangle with height and width of (size + 1)! As a consequence your screen wrap is off by one and allows coordinates 512 for x or 256 for y. The Java-based emulator or the referene OS.vm files will therefore quickly crash with ERR9 as soon as the first Boid reaches the bottom of the screen.
I would recommend to change the 2 calls in class Boid to

do Screen.drawRectangle(positionX, positionY, positionX + size - 1, positionY + size - 1);

to have a boid with the expected size (of 10).

[yokes_in_flight]

Thank you for taking the time to review this, and nice feedback!