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Collision Detection (2015)

jeffreythompson.org

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Re: Collision Detection (2015)

#3
I am positively in love with this website. It’s simple. Looks great. Works on mobile. It’s well organized with exactly the right amount of data. When dealing with algorithms you need to get right to the point. Don’t make it a dense read. And because of all these successes, this website is also a good reference.

Re: Collision Detection (2015)

#5
post #2

Very nice! A very good resource on collision detection is the book by Christer Ericson (2005). However it is more geared towards c++ realtime games. https://realtimecollisiondetection.net/ I appreciate this nice site too.

That book is in my top 3 technical books of all time. It's basically data structures for 2D/3D space.

It's also the only algorithms book I've found that actually has a whole section on how to write cache aware algorithms, pure gold.

Re: Collision Detection (2015)

#7
This is beautiful, but it seems to be missing two pretty common cases:

1. Off-axis rectangles, which are common for things like fighting games

2. Efficient convex polygon to convex polygon collision (GJK being the most popular algorithm), which is sort of the “most general” 2d collision detection problem.

Re: Collision Detection (2015)

#8
post #6

I've always defaulted to squaring the radii for circle collision to avoid the sqrt. Is it a premature optimization these days?

No, it’s not premature. Skipping sqrt operations in the inner loops, which collision detection often is, is a generally good idea because the sqrt operation isn’t cheap.

Re: Collision Detection (2015)

#9
It's a very basic intro. Polygon/polygon is brute force, O(N^2). There's no coarse filtering so that only nearby objects are checked. There's nothing that points out that concave objects are much harder to check efficiently than convex ones. Plus it's 2D only.

An intro is nice, but this is like writing about sorting and only showing bubble sort.

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