[alainbryden]

I figured caching the results of common patterns appearing in blocks of 2x2, 3x3, 4x4, etc. pixels which are surrounded by all 'off' pixels, you can easily skip many repetitive calculations.

  ----    ----
  -oo- =\ -oo-
  -oo- =/ -oo-
  ----    ----

  -----    -----    -----
  --o--    -----    --o--
  --o-- =\ -ooo- =\ --o--
  --o-- =/ ----- =/ --o--
  -----    -----    -----

  ------    ------    ------
  -oo---    -oo---    -oo---
  -oo--- =\ -o---- =\ -oo---
  ---oo- =/ ----o- =/ ---oo-
  ---oo-    ---oo-    ---oo-
  ------    ------    ------

Since repeating patterns tend to turn up a lot on their own in CGoL they would end up cached, and large blocks of n cells could be computed in 1 move rather than requiring o(8n) time. That seems to be how Hashlife works: http://en.wikipedia.org/wiki/Hashlife

[eranation]

Here is a CoffeeScript implementation of Hashlife

https://github.com/raganwald/cafeaulife

[tisme]

That does not credit Bill Gosper.

http://www-users.cs.york.ac.uk/~jowen/hashlife.html

[raganwald]

Where doesn't it give appropriate credit?

1. The description line for the Github package reads "Gosper's HashLife in CoffeeScript"

2. The readme says: "Cafe au Life implements Bill Gosper's HashLife algorithm."

3. The docs say "Cafe au Life is based on Bill Gosper's brilliant <a href="http://en.wikipedia.org/wiki/Hashlife>HashLife</a&#6...; algorithm."

[tisme]

Well, I could be wrong but I swear did an 'F3' on the page earlier to search for Gosper and it seemed like it wasn't there then.

Apologies for not being able to use a browser and falsely accusing you!

[raganwald]

Credit for ideas is important. I'd rather 100 people falsely accuse me than have one omission slip through. Thanks for caring.

[raganwald]

FYI: It has its own home page: http://recursiveuniver.se