Terminal Text Effects

Inline Visual Effects in the Terminal

Table Of Contents

• About
• Requirements
• Installation
• Usage (Application)
• Usage (Library)
• Effect Showcase
• In-Development Preview
• Latest Release Notes
• License

TTE

TerminalTextEffects (TTE) is a terminal visual effects engine. TTE can be installed as a system application to produce effects in your terminal, or as a Python library to enable effects within your Python scripts/applications. TTE includes a growing library of built-in effects which showcase the engine's features. These features include:

• Xterm 256 / RGB hex color support
• Complex character movement via Paths, Waypoints, and motion easing, with support for quadratic/cubic bezier curves.
• Complex animations via Scenes with symbol/color changes, layers, easing, and Path synced progression.
• Variable stop/step color gradient generation.
• Event handling for Path/Scene state changes with custom callback support and many pre-defined actions.
• Effect customization exposed through a typed effect configuration dataclass that is automatically handled as CLI arguments.
• Runs inline, preserving terminal state and workflow.

Requirements

TerminalTextEffects is written in Python and does not require any 3rd party modules. Terminal interactions use standard ANSI terminal sequences and should work in most modern terminals.

Note: Windows Terminal performance is slow for some effects.

Installation

pip install terminaltexteffects OR pipx install terminaltexteffects

Nix (flakes)

Add it as an input to a flake:

inputs = {
  terminaltexteffects.url = "github:ChrisBuilds/terminaltexteffects/<optional-ref>"
}

Create a shell with it:

nix shell github:ChrisBuilds/terminaltexteffects/<optional-ref>

Or run it directly:

echo 'terminaltexteffects is awesome' | nix run github:ChrisBuilds/terminaltexteffects/<optional-ref> -- beams

Nix (classic)

Fetch the source and add it to, e.g. your shell:

let
  pkgs = import <nixpkgs> {};

  tte = pkgs.callPackage (pkgs.fetchFromGitHub {
    owner = "ChrisBuilds";
    repo = "terminaltexteffects";
    rev = "<revision, e.g. main/v0.10.0/etc.>";
    hash = ""; # Build first, put proper hash in place
  }) {};
in
  pkgs.mkShell {
    packages = [tte];
  }

Usage

View the Documentation for a full installation and usage guide.

Application Quickstart

Options

TTE Command Line Options

  options:
  -h, --help            show this help message and exit
  --input-file INPUT_FILE, -i INPUT_FILE
                        File to read input from (default: None)
  --version, -v         show program's version number and exit
  --tab-width (int > 0)
                        Number of spaces to use for a tab character. (default: 4)
  --xterm-colors        Convert any colors specified in RBG hex to the closest
                        XTerm-256 color. (default: False)
  --no-color            Disable all colors in the effect. (default: False)
  --wrap-text           Wrap text wider than the canvas width. (default: False)
  --frame-rate FRAME_RATE
                        Target frame rate for the animation. (default: 100)
  --canvas-width WIDTH  Canvas width, set to an integer > 0 to use a specific
                        dimension, or use 0, or -1 to set the dimension based off the
                        input data or the terminal device, respectively. (default:
                        -1)
  --canvas-height WIDTH
                        Canvas height, set to an integer > 0 to use a specific
                        dimension, or use 0, or -1 to set the dimension based off the
                        input data or the terminal device, respectively. (default:
                        -1)
  --anchor-canvas {sw,s,se,e,ne,n,nw,w,c}
                        Anchor point for the canvas. The canvas will be anchored in
                        the terminal to the location corresponding to the
                        cardinal/diagonal direction. (default: sw)
  --anchor-text {n,ne,e,se,s,sw,w,nw,c}
                        Anchor point for the text within the Canvas. Input text will
                        anchored in the Canvas to the location corresponding to the
                        cardinal/diagonal direction. (default: sw)
  --ignore-terminal-dimensions
                        Ignore the terminal dimensions and utilize the full Canvas
                        beyond the extents of the terminal. Useful for sending frames
                        to another output handler. (default: False)

  Effect:
  Name of the effect to apply. Use <effect> -h for effect specific help.

  {beams,binarypath,blackhole,bouncyballs,bubbles,burn,canvas_test,colorshift,crumble,decrypt,dev,errorcorrect,expand,fireworks,matrix,middleout,orbittingvolley,overflow,pour,print,rain,randomsequence,rings,scattered,slice,slide,spotlights,spray,swarm,synthgrid,test,unstable,vhstape,waves,wipe}
                        Available Effects
    beams               Create beams which travel over the canvas illuminating the
                        characters behind them.
    binarypath          Binary representations of each character move through the
                        terminal towards the home coordinate of the character.
    blackhole           Characters are consumed by a black hole and explode outwards.
    bouncyballs         Characters are bouncy balls falling from the top of the
                        canvas.
    bubbles             Characters are formed into bubbles that float down and pop.
    burn                Burns vertically in the canvas.
    colorshift          Display a gradient that shifts colors across the terminal.
    crumble             Characters lose color and crumble into dust, vacuumed up, and
                        reformed.
    decrypt             Display a movie style decryption effect.
    errorcorrect        Some characters start in the wrong position and are corrected
                        in sequence.
    expand              Expands the text from a single point.
    fireworks           Characters launch and explode like fireworks and fall into
                        place.
    matrix              Matrix digital rain effect.
    middleout           Text expands in a single row or column in the middle of the
                        canvas then out.
    orbittingvolley     Four launchers orbit the canvas firing volleys of characters
                        inward to build the input text from the center out.
    overflow            Input text overflows and scrolls the terminal in a random
                        order until eventually appearing ordered.
    pour                Pours the characters into position from the given direction.
    print               Lines are printed one at a time following a print head. Print
                        head performs line feed, carriage return.
    rain                Rain characters from the top of the canvas.
    randomsequence      Prints the input data in a random sequence.
    rings               Characters are dispersed and form into spinning rings.
    scattered           Text is scattered across the canvas and moves into position.
    slice               Slices the input in half and slides it into place from
                        opposite directions.
    slide               Slide characters into view from outside the terminal.
    spotlights          Spotlights search the text area, illuminating characters,
                        before converging in the center and expanding.
    spray               Draws the characters spawning at varying rates from a single
                        point.
    swarm               Characters are grouped into swarms and move around the
                        terminal before settling into position.
    synthgrid           Create a grid which fills with characters dissolving into the
                        final text.
    unstable            Spawn characters jumbled, explode them to the edge of the
                        canvas, then reassemble them in the correct layout.
    vhstape             Lines of characters glitch left and right and lose detail
                        like an old VHS tape.
    waves               Waves travel across the terminal leaving behind the
                        characters.
    wipe                Wipes the text across the terminal to reveal characters.
    
  Ex: ls -a | python -m terminaltexteffects decrypt --typing-speed 2 --ciphertext-colors 008000 00cb00 00ff00 --final-gradient-stops eda000 --final-gradient-steps 12 --final-gradient-direction vertical

cat your_text | tte <effect> [options]

OR

cat your_text | python -m terminaltexteffects <effect> [options]

• Use <effect> -h to view options for a specific effect, such as color or movement direction.
  • Ex: tte decrypt -h

For more information, view the Application Usage Guide.

Library Quickstart

All effects are iterators which return a string representing the current frame. Basic usage is as simple as importing the effect, instantiating it with the input text, and iterating over the effect.

from terminaltexteffects.effects import effect_rain

effect = effect_rain.Rain("your text here")

for frame in effect:
    # do something with the string
    ...

In the event you want to allow TTE to handle the terminal setup/teardown, cursor positioning, and animation frame rate, a terminal_output() context manager is available.

from terminaltexteffects.effects import effect_rain

effect = effect_rain.Rain("your text here")
with effect.terminal_output() as terminal:
    for frame in effect:
        terminal.print(frame)

For more information, view the Library Usage Guide.

Effect Showcase

Note: Below you'll find a subset of the built-in effects.

View all of the effects and related information in the Effects Showroom.

Beams

Binarypath

Blackhole

Bubbles

Burn

Decrypt

Fireworks

Matrix

Orbittingvolley

Pour

Print

Rain

Rings

Slide

Spotlights

Swarm

VHSTape

Waves

In-Development Preview

Any effects shown below are in development and will be available in the next release.

Latest Release Notes

Visit the ChangeBlog for release write-ups.

New Features (0.11.0)

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New Effects (0.11.0)

• Matrix effect. Matrix digital rain effect with that ends with a final curtain and character resolve phase.

New Engine Features (0.11.0)

• Canvas is now arbitrarily sizeable. (-1 matches the input text dimension, 0 matches the terminal dimension)
• Canvas can be anchored around the terminal.
• Text can be anchored around the Canvas.
• Canvas new attributes text_[left/right/top/bottom] and text_width/height and text_center_row/center_column.
• Version switch (--version, -v)

Changes (0.11.0)

---

Effects Changes (0.11.0)

• Slice effect calculates the center of the text absolutely rather than by average line length.
• Print effect no longer moves the print head to the start of each line, only back to the first character on the next line.
• Many effects were updated to support anchoring within the Canvas.

Engine Changes (0.11.0)

• Performance improvements to geometry functions related to circles. (10.0.1)
• Gradient's support indexing and slicing.
• EffectCharacter objects no longer have a symbol attribute. Instead, the Animation class has a new attribute current_character_visual which provides access to a symbol and color attribute reflecting the character's current symbol and color. The prior EffectCharacter.symbol attribute was unreliable and represented both a formatted and unformatted symbol depending on when it was accessed. In addition, the color attribute is now a Color object and the color code has been moved into the _color_code attribute.
• EffectCharacter objects have a new attribute is_fill_character: bool.

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Effects Fixes (0.11.0)

• Fixed swarm effect not handling the first swarm (bottom right characters) resulting in missing characters in the output. (10.0.1)

Other (0.11.0)

• Keyboard Interrupts are handled gracefully while effects are animating.

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License

Distributed under the MIT License. See LICENSE for more information.