digitalsignalperson

Goal

How to launch multiple QEMU based VM's that can communicate with the outside world and between each other other without any setup on the host.

This uses two features available in qemu

• User Mode Networking stack - SLIRP
• Socket networking backend allows you to create a network of guests that can see each other

This allows us to have

digitalsignalperson

Summary

What this does: controlling volume for deck 1 or deck 2 from any interface (midi controllers, GUI, or TouchOSC) results in midi output sent back to TouchOSC to update their positions

Note: I did this without reading https://github.com/mixxxdj/mixxx/wiki/midi%20scripting and I think the midi scripting interface probably resolves the issues I had and simplifies the approach.

Work log

A google of mixxx osc turned my afternoon into this...

https://www.reddit.com/r/DJs/comments/rwq59j/djing_on_a_budget_homemade_touchosc_controller/

digitalsignalperson

#!/bin/python

import time
import subprocess
import threading


def get_device_node(name, strip_path=False):
    # output = subprocess.check_output(["xinput", "list-props", name]).decode('utf-8')
    # for line in output.splitlines():

digitalsignalperson

#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <X11/Xlib.h>
#include <X11/extensions/shape.h>
#include <X11/Xatom.h>

// Enable clickthrough, transparency, and always on top for a given window
//     x-clickthrough <windowid> <alpha (0-100)>
//

digitalsignalperson

#!/bin/bash

# From https://www.medo64.com/2022/10/native-zfs-encryption-speed-ubuntu-22-10/
# https://docs.google.com/spreadsheets/d/1spTTlEJESnVFSEsB98iVviA-l_unf6Hemx9Nh8KrBBI/edit#gid=1839759404
#
# Tweaks for faster test: only do 2 tests, only sleep 2 seconds, only use aes-256-gcm for zfs
# Tweaks to LUKS config
# don't use sync=always
# use only 1 vdev

digitalsignalperson

_source() {
    source ${BASE_DIR}/lxd/lxd-common
}

#======================
# General VM functions

vm_bash() {
    lxc exec "$VMNAME" -- bash "$@"

digitalsignalperson

mkfifo /tmp/gfifo

./xdp-screen-cast-ffmpeg.py &  # or run in another terminal
# Note the gstreamer pipeline
# 'pipewiresrc fd=%d path=%u ! videorate ! video/x-raw,framerate=60/1 ! videoconvert ! filesink location=/tmp/gfifo'
# I specified a 60/1 frameerate. You can do other pre-processing here, or offload it to ffmpeg.

# Encode the stream and pipe to netcat
# note: must specify correct resolution here
# we can now use h264_nvenc, mpegts, and anything else ffmpeg has

digitalsignalperson

if ! grep -qF "[archzfs]" /etc/pacman.conf; then
cat >> /etc/pacman.conf << 'EOF'

[archzfs]
Server = http://archzfs.com/$repo/x86_64
Server = http://mirror.sum7.eu/archlinux/archzfs/$repo/x86_64
Server = https://mirror.biocrafting.net/archlinux/archzfs/$repo/x86_64
EOF
fi
pacman-key -r F75D9D76

digitalsignalperson

#!/bin/python

import pathlib
import fnctl
import yaml
import time

# Watch for changes in other_history and merge them into local_history
local_history = pathlib.Path('~/.local/share/fish/fish_history').expanduser()
other_history = pathlib.Path('~/.local/share/fish/other_history').expanduser()

digitalsignalperson

/* --------------compact tabs--------------------*/
.workspace .mod-root .workspace-tab-header {
    width: unset;
    max-width: var(--tab-width);
    border: 1px solid var(--color-base-50);
}

/*.workspace-tab-header-inner {
    width: unset;
}*/