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Latency numbers every programmer should know

L1 cache reference ......................... 0.5 ns
Branch mispredict ............................ 5 ns
L2 cache reference ........................... 7 ns
Mutex lock/unlock ........................... 25 ns
Main memory reference ...................... 100 ns             
Compress 1K bytes with Zippy ............. 3,000 ns  =   3 µs
Send 2K bytes over 1 Gbps network ....... 20,000 ns  =  20 µs
SSD random read ........................ 150,000 ns  = 150 µs

Read 1 MB sequentially from memory ..... 250,000 ns = 250 µs

jk-gan

CUSTOM GAME ENGINES: A Small Study

A couple of weeks ago I played (and finished) A Plague Tale, a game by Asobo Studio. I was really captivated by the game, not only by the beautiful graphics but also by the story and the locations in the game. I decided to investigate a bit about the game tech and I was surprised to see it was developed with a custom engine by a relatively small studio. I know there are some companies using custom engines but it's very difficult to find a detailed market study with that kind of information curated and updated. So this article.

Nowadays lots of companies choose engines like Unreal or Unity for their games (or that's what lot of people think) because d

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Chrome Headless on EC2

For puppeteer usage

How to setup an EC2 instance to run Chrome Headless for usage with Puppeteer

1. Spin up ubuntu EC2 instance and ssh into it

ssh [email protected]

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Realtime Fluid Simulation: Projection

The core of most real-time fluid simulators, like the one in EmberGen, are based on the "Stable Fluids" algorithm by Jos Stam, which to my knowledge was first presented at SIGGRAPH '99. This is a post about one part of this algorithm that's often underestimated: Projection

MG4_F32.mp4

Stable Fluids

The Stable Fluids algorithm solves a subset of the famous "Navier Stokes equations", which describe how fluids interact and move. In particular, it typically solves what's called the "incompressible Euler equations", where viscous forces are often ignored.

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TypeScript 9 hrs 20 mins  ███████████████████▍░  92.8%
JSON       21 mins        ▊░░░░░░░░░░░░░░░░░░░░   3.6%
Elixir     13 mins        ▍░░░░░░░░░░░░░░░░░░░░   2.3%
Other      8 mins         ▎░░░░░░░░░░░░░░░░░░░░   1.3%

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#!/bin/bash

# Simple script to change crlf to lf.
# To start: Put in gitignore folder and run.
# Note: ^.* files are not supported

ignore_name=()
ignore_path=()
ignore_extension=()
ignore_extension+=('.sh')

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Note

Use ^#.*\n to select all the extra comments in Gemfile

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# Creates a model and controller, then adds a resource route to your routes.rb file.
rails g resource <attribute>:<type>  <attribute>:<type>

# Just like rails g scaffold, but doesn't create the model.
rails g scaffold_controller <name>

# Creates a coffeescript/javascript and corresponding (s)css file.
rails g assets <name>

# Creates a jbuilder file