All posts by mrscottm

Uncategorized

More Wayfire Animations

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In this post, we introduce two more animations, shatter and vortex. These two build on the concepts and infrastructure found in the previous animation code. I will focus more on the shatter animation, as it is more technically involving.

Shatter, as you might have guessed from the name, is an animation that fragments the surface into polygons and explodes them into the scene, when closing a window. When opening a window, the reverse implosion is in order. To do this, a way was needed to fragment the rectangular surface into irregular convex polygons. After searching around a bit on the web, I noticed the Voronoi diagrams concept. After learning that boost library offered some useful functions, it was off to test them.

At first, creating a Voronoi diagram was confusing. But after rendering it visually, it started to make sense. Input random points over the surface geometry and get output of convex polygons, suitable for rendering each as a triangle fan. With this in hand, the next step was obvious: rotate the polygons and translate them into an exploding fashion. However there was one small problem. The library doesn’t offer the center point of the polygon, required for rotation. After thinking a bit, I found a simple solution: compute the bounding box of each polygon and take the center of that. This worked remarkably well as it was fast. The only caveat is that the code walk the cells twice, once to get all the points required to know the bounding box and thus center point, and another to use this information when writing the vertices that the shader will use. The first iteration probably can be done once up front at animation creation instead of each frame, but this is yet to be implemented.

Vortex is a fragment shader that sucks the pixels into the center on close and the opposite on open. Now let’s watch some videos!

Wayland

Wayfire Animations

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Wayfire is maturing nicely with an animation infrastructure that makes it relatively easy to create new animations. However, even though wayfire has the nice fire animation, it only has a few other basic ones. Recently, wayfire gained support for a new option type of ‘animation’. This type allows you to select an easing as well as duration. One animation that wayfire users have been talking about for years, is the classic magic lamp minimize animation. And secretly, I’ve been wanting to write this animation. After a comment from a user in wayfire chat about this animation being the only thing missing from their wayifre-dots setup, I figured it was time to try my hand at implementing the effect. I decided to call it ‘squeezimize’, and started coding.

At first, I rendered the view in a loop, scissoring the transformed surface into horizontal lines. This worked ok, but the sigmoid curve seemed to be lost in the math, and worst of all, the implementation was slow. After bouncing around some ideas to make it faster, it seemed the way forward was to write a fragment shader to render the effect in a single pass per frame. After a lot more math and coffee, I came up with this very thing. A simple fragment shader that requires minimum glsl version and only uses basic math. It does not use builtin shader functions other than clamp(). This means it’s fast. And, the shader renders better curves than the slower line by line proof of concept.

TL;DR: Wayfire has a new shader called squeezimize that renders a magic lamp effect. Yes it’s been done, time and time again, but because it’s a single pass shader with very little input, it’s low on resources. After writing squeezimize, I wrote two more animations for wayfire open/close windows, called zap and spin. Now for a video:

EDIT: There are now two more animations, in addition to the above, helix and blinds:

 

Random, Uncategorized

Streaming RTSP directly to browsers

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Let’s not sugar coat it, streaming video is a complex topic. If every browser had the same video player, it might make things a bit easier. But of course, they don’t. So, I’ll try to dumb this down, keep it short and make it as simple as possible.

If you have some RTSP H.264 streams that you want to stream to Firefox or Chrome with minimal latency, you might be in for a treat. Using nodejs and ffmpeg, we can serve up the streams while convincing the browser to play the stream immediately while buffering with minimal latency. How? As I found, it is not easy. But let’s act like it was, shall we?

In a nutshell, a browser first makes an initial GET for the url and the server replies with a video/mp4 mime type header with 200 status. We start up ffmpeg and have it write to stdout but we don’t send any of the data on this request. This behooves the client to make a range request. Next, on the range request, the client is expecting a file so it asks for portions of it. Here, we always tell it the start is 0 and do some math to tell it what range and length to expect, based on the bytes we have so far, and send 206 status. Then, we start sending the data. Getting this right was only half the battle though..

TL;DR, I checked the agent string to see if it’s chrome or not. If it’s chrome, we use `ffmpeg -f matroska` but for firefox, we have to use `ffmpeg -f mp4` since it doesn’t have matroska support. The confusing thing was that the mime type could not be video/x-matroska because that caused the browser to attempt downloading the file. Now on to the code.

The following is a snippet to stream RTSP directly to firefox or chrome browsers:

function serve_rtsp(req, res, ip, user, pass) {
    user_agent_string = req.get('user-agent');
    const range = req.headers.range;
    if (range)
    {
        if (!running)
        {
            res.end();
            return;
        }
        const start = 0;
        const end = Math.max(total_length, 1024 * 1024 * 32);
        const chunk_size = end + 1;
        res.writeHead(206, {'Accept-Ranges': 'bytes', 'Content-Range': 'bytes ' + start + '-' + end + '/' + chunk_size, 'Content-length': chunk_size, 'Content-Type': 'video/mp4', 'Connection': 'keep-alive'});
        ffmpeg.stdout.unpipe();
        ffmpeg.stdout.pipe(res);
        return;
    } else
    {
        res.writeHead(200, {'Accept-Ranges': 'bytes', 'Content-Type': 'video/mp4', 'Connection': 'keep-alive'});
    }
    if (running)
    {
        ffmpeg.kill("SIGINT");
        total_length = 0;
        clearTimeout(ffmpeg_timer);
    }
    if (user_agent_string.includes("Chrome"))
    {
        ffmpeg = child_process.spawn("ffmpeg",[
        "-i", 'rtsp://' + user + ':' + pass + '@' + ip + ':80',
        "-f", "matroska",  // File format
        "-c", "copy",      // No transcoding
        "-t", "60",        // Timeout
        "-"                // Output (to stdout)
        ]);
    }
    else
    {
        ffmpeg = child_process.spawn("ffmpeg",[
        "-i", 'rtsp://' + user + ':' + pass + '@' + ip + ':80',
        "-f", "mp4",       // File format
        "-movflags", "empty_moov+frag_keyframe",
        "-c", "copy",      // No transcoding
        "-t", "60",        // Timeout
        "-"                // Output (to stdout)
        ]);
    }
    running = true;
    res.end();
    ffmpeg.stdout.on('data', ffmpeg_handle_data);
    ffmpeg_timer = setTimeout(function() {
        running = false;
    }, 60000);
}

I hope this is helpful to someone out there. If you do find it useful and want to say thanks, you can donate a coffee on northfield.ws.

 

Wayland

Decoration Adventures

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Wayfire has decoration plugins and even a shadow plugin available. The shadow plugin works great, for square decorations at least. Adding rounded corners with shadows that hug them would be a nice addition. So, I set out to do that, and the results even surprised me.

I started hacking on pixdecor plugin, first porting it to work with latest wayfire, then adding compute shader support for decoration animations, patterns and overlay effects. Out of all the things, none of the effects had a need to render beyond the decoration area, into the shadow region. This basically meant making the rendering area larger, to have a place to scribble in some shadows. The concept is simple but implementing it required changing the code very carefully in many different places. Even after getting it right, changing some settings might make the decoration the wrong size or some other problem (like crashing). After shaking out the bugs for the shadow padding, it was time to shade some shadows.

I knew I wanted simple code that got straight to the point. After poking around a bit on shadertoy and not finding what I wanted, I decided to write the shader from scratch. Here’s the path I ended up with. First, the decoration is cleared using a clear color or otherwise filled in with an effect shader. Then, the overlay shader is applied. The overlay has eight conditionals, one for each side and one for each corner. For the sides, it measures the distance from the edge to the pixel color being written and mixes transparent with the shadow color, depending on how far away it is. The corner is the same recipe but it picks a single point in the corner and uses it to measure the corner and shadow radius. This means that even though the corners are rounded, the shadows follow the curvature. The other nice thing about the overlay is that is automatically anti-aliases the edges of the rounded corners by mixing, instead of just discarding pixels or other method that leaves jagged corner edges.

All of this, and everything is configurable in real time, from the border size to the corner radius and shadow radius, color, etc. It took some careful coding to make everything work together but in the end, it is working nicely, with great performance. Now, for the video:

Wayland

Wayfire Smoke

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A wayfire user decided to port weston smoke into wayfire and while it worked, it was quite slow, even at modest sizes. I patched weston smoke to be resizable but this only showed how slow the cpu-bound algorithm is. So, I decided to try my hand at making it faster, using a compute shader. At first, there was a single shader but realized that each loop needed its own shader. It was also slow at first but after tweaking the workgroups per dispatch and the workgroup size in each shader, the difference was multi-fold. It took some time to implement and optimize but it worked out pretty well. The code has been uploaded here. The performance improvement results are astounding and there isn’t much else to do than watch some comparison videos:

Original Weston Smoke Client:

Implementation in a Decorator:

Side by Side Standalone Clients:

Wayland

Wayfire Ubuntu Packages

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After more than a few requests for wayfire deb packages that work on ubuntu, I decided to try creating some. The result is a success. This is how I did it.

First, I started with the latest code. I will cover wayland and wayfire packages. There are others that are required, but these two are different in that wayland packages are already in ubuntu but there are none for wayfire.

For wayland, we will copy the debian directory, containing the interesting files for building a package from upstream, and place it in the upstream code directory.

$ git clone https://git.launchpad.net/ubuntu/+source/wayland wayland-ubuntu
$ git clone https://gitlab.freedesktop.org/wayland/wayland wayland-upstream
$ cp -r wayland-ubuntu/debian wayland-upstream

Next, we want to prepare the environment by installing the build dependencies.

$ sudo apt-get build-dep wayland
$ sudo apt install gcc g++ meson ninja debhelper dh-make

Finally we want to configure and build the packages.

$ dh_auto_configure --buildsystem=meson
$ dpkg-buildpackage -rfakeroot -us -uc -b

This results in the following packages:

libwayland-bin_1.19.90-1_amd64.deb
libwayland-client0_1.19.90-1_amd64.deb
libwayland-cursor0_1.19.90-1_amd64.deb
libwayland-dev_1.19.90-1_amd64.deb
libwayland-egl1_1.19.90-1_amd64.deb
libwayland-egl-backend-dev_1.19.90-1_amd64.deb
libwayland-server0_1.19.90-1_amd64.deb

For wayfire, the process is similar but we need to generate the debian files. Install dependencies manually, by satisfying meson first.

$ git clone https://github.com/WayfireWM/wayfire && cd wayfire
$ dh_make --createorig -p wayfire_0.8.0
$ dh_auto_configure --buildsystem=meson
$ dpkg-buildpackage -rfakeroot -us -uc -b
$ ls ../*.deb
../wayfire_0.8.0-1_amd64.deb

Here is a PPA containing all the packages needed for wayfire on Ubuntu >=20.04. To install wayfire:

$ sudo add-apt-repository ppa:soreau/wayfirewm
$ sudo apt-get update
$ sudo apt install wayfire wayfire-plugins-extra wf-shell wcm xwayland

Launch wayfire by running it from X or tty, or simply logout and select the Wayfire session.
To remove completely:

$ sudo apt install ppa-purge
$ sudo ppa-purge ppa:soreau/wayfirewm
Wayland

Wayfire

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Usually I blog about compiz after a release but I wanted to share something different. There is a C++ wayland/wlroots compositor by Ilia Bozhinov in the works that has many compiz-like features. It’s called Wayfire and it has quite a few bells so far. It functions on a plugin based system much like compiz and the API is fairly nice. I’ve written wcm,  a configuration GUI for wayfire inspired heavily by ccsm. There are videos on the website at wayfire.org you can view to see the basics. It will only work with drivers offering gbm however, which basically means it works with open source drivers. Wayfire and wlroots are very much in development so the bleeding edge may not work but when it does, it’s fire.
General build guide for ubuntu 18.04:

1) Install dependencies from packages.

$ sudo apt install git python3-pip pkg-config libwayland-dev autoconf libtool libffi-dev libxml2-dev libegl1-mesa-dev libgles2-mesa-dev libgbm-dev libinput-dev libxkbcommon-dev libpixman-1-dev xutils-dev xcb-proto python-xcbgen libcairo2-dev libglm-dev libjpeg-dev libgtkmm-3.0-dev xwayland

2) Install meson and ninja.

$ pip3 install meson ninja; . ~/.profile

3) Export prefix, PATH and PKG_CONFIG_PATH variables.

$ export prefix=/opt/wayfire
$ export PATH=$prefix/bin:$PATH
$ export PKG_CONFIG_PATH=$prefix/lib/pkgconfig:$prefix/share/pkgconfig:$prefix/lib/x86_64-linux-gnu/pkgconfig

4) Create the installation directory and change user and group so we can install the software as user. Also create a src directory to hold the source code.

$ sudo mkdir $prefix; sudo chown $USER:$USER $prefix
$ mkdir ~/src; cd ~/src

5) Clone the source we will need.

$ git clone https://gitlab.freedesktop.org/wayland/wayland
$ git clone git://anongit.freedesktop.org/wayland/wayland-protocols
$ git clone git://anongit.freedesktop.org/xcb/libxcb
$ git clone https://github.com/swaywm/wlroots
$ git clone https://github.com/WayfireWM/wayfire
$ git clone https://github.com/WayfireWM/wf-shell
$ git clone https://github.com/WayfireWM/wcm

6) Build the source code.

$ cd ~/src/wayland && ./autogen.sh --prefix=$prefix --disable-documentation && make && make install
$ cd ~/src/wayland-protocols && ./autogen.sh --prefix=$prefix && make && make install
$ cd ~/src/libxcb && ./autogen.sh --prefix=$prefix && make && make install
$ cd ~/src/wlroots && meson build --prefix=$prefix && ninja -C build && ninja -C build install
$ cd ~/src/wayfire && meson build --prefix=$prefix && ninja -C build && ninja -C build install
$ cd ~/src/wf-shell && meson build --prefix=$prefix && ninja -C build && ninja -C build install
$ cd ~/src/wcm && meson build --prefix=$prefix && ninja -C build && ninja -C build install

7) Copy config files in place and modify them a bit.

$ cp ~/src/wayfire/wayfire.ini.default ~/.config/wayfire.ini
$ cp ~/src/wf-shell/wf-shell.ini.example ~/.config/wf-shell.ini
$ sed -i 's/env XDG_CURRENT_DESKTOP=GNOME gnome-control-center/wcm/' ~/.config/wf-shell.ini

Optionally set a background image in ~/.config/wf-shell.ini from your system.

8) Save this script as /usr/local/bin/wayfire.

#!/bin/bash

prefix=/opt/wayfire
log_file=/tmp/wayfire.log

export PATH="$prefix"/bin:$PATH
export XDG_DATA_DIRS="$prefix"/share:$XDG_DATA_DIRS
export GTK_THEME=Adwaita:dark
export GDK_BACKEND=wayland
export QT_QPA_PLATFORM=wayland
export LD_LIBRARY_PATH="$prefix"/lib:"$prefix"/lib/x86_64-linux-gnu/
exec "$prefix"/bin/wayfire "$@" &> "$log_file"

8b) Make it executable.

$ sudo chmod +x /usr/local/bin/wayfire

9) Run it.

$ /usr/local/bin/wayfire

9b) Open an application. Either run a native terminal,

WAYLAND_DISPLAY=wayland-0 GDK_BACKEND=wayland terminator

or an X11 one.

DISPLAY=:1 xterm

10) Optionally switch to tty to use the drm backend. Make sure your user is part of the video group to run as user.

sudo adduser $USER video

11) Optionally create /usr/share/wayland-sessions/wayfire.desktop to login from lightdm.

[Desktop Entry]
Version=1.0
Name=Wayfire Session
Comment=Use this session to run Wayfire as your desktop environment
Exec=/usr/local/bin/wayfire
Type=Application

Firefox nightly should work as a native browser. Ctrl+Alt+Bckspc to log out. Any questions should be asked in #wayfire on irc.freenode.net or an issue filed on github for the relevant component. To remove the compiled packages and source, remove /opt/wayfire/, ~/src/, /usr/local/bin/wayfire and /usr/share/wayland-sessions/wayfire.desktop. Checkout wayfire.org for more information.

Compiz

Compiz Release Announcement – 0.8.14

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It’s time for Compiz Reloaded 0.8.14. Here is the changelog:

– Whisker menu resize bug fix
– Improved horizontal and vertical maximizing
– Removed the “Number of Desktops” option
– Fixed crash when displaying special characters in gtk-window-decorator and emerald
– Set rotate and wall default flip bindings to None, which mitigates the problem where edges of screen are unclickable
– Fix potential for skydome silently failing to render
– Don’t fallback for exceeding max texture size
– Improved –button-layout behavior for gtk-window-decorator
– Updated translations
– Introduced window state selector in ccsm
– Improvements to elements, staticswitcher, static and notification plugins
– Added more colorfilters
– Added models for cubemodel plugin
– Added default enabled option for stars, fireflies, wizard and snow
– Increase maximum text size for relevant plugins
– Added earth plugin (built where libcurl and libglew dependencies are available)

The packages can be found here.

There is a script available to install the compiz suite. To use it:

Step 1) – Install Xubuntu 17.04 or your debian-based Linux distribution flavor with sudo installed.

Step 2) – Install git

$ sudo apt-get install git

Step 3) – Download the build script set. Optionally omit ‘-b release-0.8.14’ to build latest compiz-reloaded git master

$ git clone git://northfield.ws/compiz/scripts -b release-0.8.14

Step 4) – Run the INSTALL script

$ ./scripts/go

Step 5) – Start ccsm by typing ccsm in the terminal and verify it runs

$ ccsm

Step 6) – Enable basic plugins such as Window Decoration, Move Window, Place Window, Resize Window and maybe Wobbly so you know it’s working

Step 7) – Start compiz with

$ compiz --replace ccp

Step 8) – Start a compiz window decorator

$ gtk-window-decorator --replace

If everything is working, then congratulations! If not, you can ask in #compiz or #compiz-reloaded on chat.freenode.net or file an issue on github.

The script set includes an uninstall script used to remove everything if needed. Run ./scripts/uninstall to use it.

This version of compiz and other 0.8.x versions may conflict with any 0.9.x compiz, ccsm, emerald or other compiz 0.9.x components.

DISCLAIMER: Not responsible for crazed kittens, disgruntled gnomes or volcanic paint eruptions.

Enjoy!

Compiz

Compiz Release Announcement – 0.8.12

15 Comments

Hello again. We have joined forces with the mate-compiz team and adopted the new name, Compiz Reloaded. We’ve also moved to github and Compiz 0.8.12 is ready. Here is the changelog:

– Add font family configuration for plugins that draw text such as Group/Tab, Scale Window Title Filter and Workspace Names plugins
– Lessen probability of “white glitches” that happen on resize using gtk-window-decorator and emerald
– gtk-window-decorator, emerald, ccsm, simple-ccsm and fusion-icon support both gtk2 and gtk3
– Fix right click near top edge of maximized windows in gtk-window-decorator and emerald
– Add an option to emerald-theme-manager to disable shading when titlebar is scrolled
– Rename plugins-unsupported to plugins-experimental and add many more plugins
– Change minimum and default amount of waves to 0 for Magic Lamp animation
– Add support for a Super Maximize button in emerald (toggles fullscreen)
– Various fixes for ccsm, simple-ccsm and fusion-icon
– Address vs problem more fully
– Increase maximum Mipmap LOD for Blur plugin
– Move Desktop Wall plugin to core
– Lots of additional Mate support
– Fix crash related to animations
– Fix memory leaks in emerald

The packages can be found here.

There is a script used to install the compiz suite. To use it:

Step 1) – Install Xubuntu 15.10 or your variant of debian-based Linux distribution with sudo installed.

Step 2) – Install git

$ sudo apt-get install git

Step 3) – Download the build script set. Optionally omit -b release-0.8.12 to build latest compiz-reloaded master

$ git clone git://northfield.ws/compiz/scripts -b release-0.8.12

Step 4) – Run the INSTALL script

$ ./scripts/go

Step 5) – Start ccsm by typing ccsm in the terminal and verify it runs

$ ccsm

Step 6) – Enable basic plugins such as Window Decoration, Move Window, Place Window, Resize Window and maybe Wobbly so you know it’s working

Step 7) – Start compiz with

$ compiz --replace ccp

Step 8) – Start a compiz window decorator

$ gtk-window-decorator --replace

If everything is working, then congratulations! You can add ‘gtk-window-decorator’ (without quotes) to ccsm>Effects>Window Decoration>Command field so gtk-window-decorator starts when compiz does. If not, you can ask in #compiz or #compiz-reloaded on chat.freenode.net. Enjoy!

AUDIENCE: This information is targeted toward those familiar with Linux distributions and FOSS.

INFORMATION: The script set includes an uninstall script used to remove everything. Run ./scripts/uninstall to use it.

WARNING: This software and other 0.8.x versions may conflict with any 0.9.x compiz, ccsm, emerald or other compiz 0.9.x components.

DISCLAIMER: Not responsible for unhappy camping, confused vulkans or exploding pixels.

Random

32bit chroot environment on 64bit Ubuntu

2 Comments

Recently, I wanted to setup a chroot environment to build a 32bit library on 64bit host platform. After failing several times trying different things, reading man pages and scouring the web for a solution, I did not find what I was looking for. So, I decided to make this post. Here is what I came up with.

Components:

  1. debootstrap
  2. schroot

Assumptions:

  1. Ubuntu Trusty 64bit host
  2. Ubuntu Trusty 32bit target
  3. Target directory /opt/chroot/trusty-i386/
  4. You know what you’re doing

TLDR:

Install debootstrap and schroot:

# apt-get install debootstrap schroot

Replace your-user-name with the name of your user in the following and put it in /etc/schroot/schroot.conf:

[trusty]
description=Trusty Tahr (i386)
directory=/opt/chroot/trusty-i386
users=your-user-name
root-groups=root
preserve-environment=true
personality=linux32

Run these commands (once) to setup the environment:

# export target_dir="/opt/chroot/trusty-i386"
# apt-get install debootstrap schroot
# debootstrap --include=apt,apt-utils,sudo,dialog --variant=buildd --foreign --arch i386 trusty "$target_dir" http://archive.ubuntu.com/ubuntu/
# chroot "$target_dir" debootstrap/debootstrap --second-stage
# bash -c "echo \"chroot\" > \"$target_dir\"/etc/debian_chroot"
# bash -c "echo \"deb http://us.archive.ubuntu.com/ubuntu/ trusty main restricted universe multiverse\" >> \"$target_dir\"/etc/apt/sources.list"
# bash -c "echo \"deb-src http://us.archive.ubuntu.com/ubuntu/ trusty main restricted universe multiverse\" >> \"$target_dir\"/etc/apt/sources.list"
# chroot "$target_dir" apt-get update
# chroot "$target_dir" locale-gen $LANG

Use this script to enter the chroot (run as user):

#!/bin/bash

target_dir="/opt/chroot/trusty-i386"

sudo mount -o bind /proc "$target_dir"/proc/
sudo mount -o bind /sys "$target_dir"/sys
sudo mount -o bind /dev "$target_dir"/dev
sudo mount -o bind /dev/pts "$target_dir"/dev/pts
sudo mount -o bind /home "$target_dir"/home

sudo cp /etc/resolv.conf "$target_dir"/etc/resolv.conf
sudo cp /etc/hosts "$target_dir"/etc/hosts
sudo cp /etc/passwd "$target_dir"/etc/passwd
sudo cp /etc/shadow "$target_dir"/etc/shadow
sudo cp /etc/group "$target_dir"/etc/group
sudo cp /etc/services "$target_dir"/etc/services
sudo cp /etc/protocols "$target_dir"/etc/protocols
sudo cp /etc/networks "$target_dir"/etc/networks

schroot -c trusty

sudo umount "$target_dir"/proc/ "$target_dir"/sys/ "$target_dir"/dev/pts "$target_dir"/dev/ "$target_dir"/home

To remove the chroot environment completely:

rm -rf /opt/chroot/trusty-i386/*

Notes:

Using schroot is optional, you should be able use the environment ‘normally’ with chroot. I’m not sure why the files in /etc/schroot/default/ are seemingly unused, possibly something to do with a missing schroot config script. The debootstrap program completes leaving /etc/apt/sources.list* empty, perhaps something to do with debian bug #736995, so we populate the sources.list file manually. You may add additional packages you want installed to the –include line. Running debootstrap with –second-stage in the chroot installs these additional packages amongst other things. We also create /etc/debian_chroot with the contents “chroot” so the command prompt is prefixed with “(chroot)”, making it clear that it’s not running the host shell. Installing apt-utils and running locale-gen isn’t particularly necessary but at least it gets rid of some annoying messages when running certain dpkg related commands. The script shown mounts the important directories and copies relevant files needed to chroot into a working environment. One caveat is that it might ask for password after exit for umount. Optionally, corresponding fstab entries could be made and copy the relevant files once, so only the schroot command would be needed. This should be enough to login as your user with access to $HOME and to build and run applications, including X11 apps. Cheers.