snowtrix

Snow falling in your terminal.

snowtrix is a small interactive particle engine written in C99 with termbox2. It brings falling snow, wind, accumulation, and mouse interaction to a terminal window without trying to be a full game or a complex graphics project.

The idea is simple: open a terminal, let the snow fall, and play with the simulation when you feel like it.

Features

• Interactive Snow: Snowflakes fall with different speeds, movement, and depth layers.
• Wind System: Change the direction and strength of the wind while the simulation is running.
• Snow Accumulation: Let snow build up on the ground and slowly spread across the surface.
• Mouse Physics: Move or click the mouse to push snowflakes around and dig into accumulated snow.
• Parallax Layers: Three particle layers create a simple sense of depth.
• Spring Mode: Melt accumulated snow dynamically while the simulation continues.
• Party Mode: Switch from normal snow colors to animated RGB colors.
• Color Presets: Change the snow theme instantly while the program is running.
• Lightweight: Written in C99 with POSIX support and designed to run directly in the terminal.

Showcase

Dynamic Snowfall	Interactive Physics

Requirements

• Linux / POSIX system
• GCC or Clang with C99 support
• GNU Make
• ncursesw and libm

termbox2 is included directly in the source tree, so there is no separate termbox2 installation step.

Installation

Clone the repository and build the program:

git clone https://github.com/opendoto/snowtrix.git
cd snowtrix
make

Run it directly from the project directory:

./snowtrix

To install it system-wide:

sudo make install

To remove the installed binary:

sudo make uninstall

To remove local build files:

make clean

Command Line Options

Usage: snowtrix [OPTIONS]

OPTIONS:
  -a           Enable snow accumulation on startup
  -p           Start directly in Party Mode
  -c <RRGGBB>  Set foreground snow color
  -m <RRGGBB>  Set middle layer color
  -f <RRGGBB>  Set background layer color
  -C <theme>   Use a predefined color theme
  -s <speed>   Set initial falling speed
  -w <wind>    Set initial wind force
  -b <flakes>  Set the number of active snowflakes
  -h, --help   Show help message

Runtime Controls

General

Key	Action
q / ESC	Quit
a	Toggle snow accumulation
s	Toggle Spring Mode (automatic melting)
p	Toggle Party Mode

Environment

Key	Action
> / .	Increase wind to the right
< / ,	Increase wind to the left
w	Calm the wind
+ / =	Increase falling speed
- / _	Decrease falling speed
m	Add 50 snowflakes
l	Remove 50 snowflakes

Color Presets

Key	Color	Key	Color
!	Red	%	Magenta
@	Green	^	Cyan
#	Yellow	&	White
$	Blue	)	Dark Gray

Limitations & Known Issues

Keep in mind that snowtrix is a terminal-based particle engine, so some behavior depends on the terminal emulator being used:

• Terminal Resizing: Resizing the terminal while the simulation is running can cause small visual artifacts during the redraw.
• Mouse Support: Mouse interaction requires a terminal emulator with mouse tracking support.
• Unicode Rendering: Snowflake shapes may look different depending on the terminal font and Unicode support.

AI Disclaimer

Full disclosure: parts of this codebase were developed with the assistance of an AI tool. I designed the project concept, feature direction, physics behavior, and overall requirements, using AI as a pair programmer to help with implementation, debugging, and code cleanup.

License

MIT License. See LICENSE for details.