savetheclocktower

Using a rotary encoder as a volume control

On my RetroPie machine I wanted a hardware volume knob — the games I play use a handful of emulators, and there's no unified software interface for controlling the volume. The speakers I got for my cabinet are great, but don't have their own hardware volume knob. So with a bunch of googling and trial and error, I figured out what I need to pull this off: a rotary encoder and a daemon that listens for the signals it sends.

Rotary encoder

A rotary encoder is like the standard potentiometer (i.e., analog volume knob) we all know, except (a) you can keep turning it in either direction for as long as you want, and thus (b) it talks to the RPi differently than a potentiometer would.

I picked up this one from Adafruit, but there are plenty others available. This rotary encoder also lets you push the knob in and treats that like a button press, so I figured that would be useful for toggling mute on and off.

Kartones

PSQL

Magic words:

psql -U postgres

Some interesting flags (to see all, use -h or --help depending on your psql version):

• -E: will describe the underlaying queries of the \ commands (cool for learning!)
• -l: psql will list all databases and then exit (useful if the user you connect with doesn't has a default database, like at AWS RDS)

danieleggert

GPG and git on macOS

Setup

No need for homebrew or anything like that. Works with https://www.git-tower.com and the command line.

1. Install https://gpgtools.org -- I'd suggest to do a customized install and deselect GPGMail.
2. Create or import a key -- see below for https://keybase.io
3. Run gpg --list-secret-keys and look for sec, use the key ID for the next step
4. Configure git to use GPG -- replace the key with the one from gpg --list-secret-keys

endolith

ּ_בּ
בּ_בּ
טּ_טּ
כּ‗כּ
לּ_לּ
מּ_מּ
סּ_סּ
תּ_תּ
٩(×̯×)۶
٩(̾●̮̮̃̾•̃̾)۶

andreyvit

tmux cheat sheet

(C-x means ctrl+x, M-x means alt+x)

Prefix key

The default prefix is C-b. If you (or your muscle memory) prefer C-a, you need to add this to ~/.tmux.conf:

remap prefix to Control + a

maxim

#!/usr/bin/env bash
#
# gh-dl-release! It works!
# 
# This script downloads an asset from latest or specific Github release of a
# private repo. Feel free to extract more of the variables into command line
# parameters.
#
# PREREQUISITES
#

lelandbatey

Description

This simple script will take a picture of a whiteboard and use parts of the ImageMagick library with sane defaults to clean it up tremendously.

The script is here:

#!/bin/bash
convert "$1" -morphology Convolve DoG:15,100,0 -negate -normalize -blur 0x1 -channel RBG -level 60%,91%,0.1 "$2"

Results

dianjuar

Requirements

• maim
• xclip

Set-up

Set this on your i3 config file ~/.i3/config

# Screenshots

mattratleph

vimdiff cheat sheet

##git mergetool

In the middle file (future merged file), you can navigate between conflicts with ]c and [c.

Choose which version you want to keep with :diffget //2 or :diffget //3 (the //2 and //3 are unique identifiers for the target/master copy and the merge/branch copy file names).

:diffupdate (to remove leftover spacing issues)

:only (once you’re done reviewing all conflicts, this shows only the middle/merged file)

varemenos

Get Git log in JSON format

git log --pretty=format:'{%n  "commit": "%H",%n  "abbreviated_commit": "%h",%n  "tree": "%T",%n  "abbreviated_tree": "%t",%n  "parent": "%P",%n  "abbreviated_parent": "%p",%n  "refs": "%D",%n  "encoding": "%e",%n  "subject": "%s",%n  "sanitized_subject_line": "%f",%n  "body": "%b",%n  "commit_notes": "%N",%n  "verification_flag": "%G?",%n  "signer": "%GS",%n  "signer_key": "%GK",%n  "author": {%n    "name": "%aN",%n    "email": "%aE",%n    "date": "%aD"%n  },%n  "commiter": {%n    "name": "%cN",%n    "email": "%cE",%n    "date": "%cD"%n  }%n},'

The only information that aren't fetched are:

• %B: raw body (unwrapped subject and body)
• %GG: raw verification message from GPG for a signed commit