Rotating Points in 2D Space | Coding a 2D Physics Engine in Java #5

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United States GamesWithGabe
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Published on ● Video Link: https://www.youtube.com/watch?v=dlUcIGnaAnk


Duration: 26:55
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In this episode, I go over a mathematical proof that shows how to rotate points around other points in 2D space. After I go over the proof, we implement the proof in code so that we can use it to rotate any Vector2f's around other Vector2f's. I also go over floating point comparison, how to compare to floating point numbers to an epsilon roundoff value, and we implement that as well. Lastly, I go over how to check if a point is inside an OBB (oriented bounding box) by transforming the point to the box's local space, then using the AABB formula.

Khan Academy Videos: https://www.khanacademy.org/partner-content/pixar/sets/rotation/v/sets-8
Floating Point Comparison: http://realtimecollisiondetection.net/blog/?p=89

Source Code: https://github.com/codingminecraft/MarioYoutube/tree/81e60b338f60b29e9414200c93c16945eba910b9

0:00 Intro
1:08 The Proof
14:29 Coding the Proof
18:08 Comparing Floating Point Numbers
22:18 Checking if Point is in OBB

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Website: https://ambrosiogabe.github.io/
Github: https://github.com/ambrosiogabe

Here are some books I recommend if you want to learn about game engine development more thoroughly. I do not profit off any of these sales, these are just some books that have helped me out :)

My Recommended Game Engine Books:
Game Engine Architecture: https://www.gameenginebook.com/
Game Physics Cookbook (Read this before the next physics book): https://www.amazon.com/Game-Physics-Cookbook-Gabor-Szauer/dp/1787123669
Game Physics (Ian Millington): https://www.amazon.com/Game-Physics-Engine-Development-Commercial-Grade/dp/0123819768
Game Programming Patterns (Free): https://gameprogrammingpatterns.com/

My Recommended Beginning Game Programming Books:
JavaScript Game Design: https://www.apress.com/gp/book/9781430247166

My Recommended Java Books:
Data Structures/Algorithms: https://www.amazon.com/Data-Structures-Algorithms-Java-6th-ebook/dp/B00JDRQF8C
LWJGL (Free, but I haven't read this thoroughly): https://lwjglgamedev.gitbooks.io/3d-game-development-with-lwjgl/content/

Outro Music: https://www.bensound.com/royalty-free-music



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