Retro Plasma

retro-plasma is a full-screen animation demo that renders a classic plasma effect directly in the terminal. It is both a visual showcase and a practical example of continuous buffer updates, palette switching, keyboard controls, and resize-aware rendering.

Use This Demo When You Need…

• A support example for continuous full-screen animation with keyboard input.

• A place to study palette-based color animation with ColorSequence.

• A lively example of a resize-aware terminal application that still keeps its controls readable.

Run the Demo

Start the demo from the build directory:

$ ./cmake-build-debug/demo-apps/cterm/retro-plasma

Use F to speed up, S to slow down, P or Space to pause, C to switch palettes, and Q to quit.

Captured Output (80x25)

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Retro Plasma [Q] quit [F] faster [S] slower [P] pause [C] palette speed 100%

The capture may not show the terminal output correctly. Here a screenshot:

Features Demonstrated

• Full-screen rendering using Buffer together with Terminal::updateScreen().

• A timed animation loop combined with keyboard input in Input::Mode::Key.

• Palette-based color animation implemented with ColorSequence.

• Resize-aware rendering using custom UpdateSettings with minimum-size handling.

• A dynamic footer prompt composed from colored BlockString fragments.

Related Demos

• Frame Color Animations for a more structured view of repeated updateScreen() calls.

• Frame Color Animations for a simpler, frame-focused color animation example.

• Key Input Demo for another example of immediate input in a full-screen animation loop.

Relevant Source Files

If you want to explore how the effect is implemented, start with demos/cterm/RetroPlasma/src/RetroPlasmaApp.cpp and demos/cterm/RetroPlasma/src/PlasmaRenderer.cpp.