wlgol/openspec/changes/gol-simulation/proposal.md

Proposal

Why

The application now supports input, pattern placement, and HiDPI rendering, but has no Game of Life dynamics. This change adds the actual automaton: Conway's rules, pause/resume, single stepping, speed control, and mouse editing of cells, so the tool becomes usable for exploring patterns.

What Changes

• Add Conway's Game of Life simulation that updates the cell grid on a timer.
• Start paused by default; allow pause/resume, single-step, and speed changes.
• Allow mouse editing of cells (left click sets alive, right click sets dead) only while paused, including drag painting.
• Add default key bindings for pause (p), step (n), and speed (+/-).
• Render simulation state and reflect pause/editing in the UI (via stdout status).

Capabilities

New Capabilities

• gol-simulation: Conway rules, tick timing, pause/resume, stepping, speed control, and paused-only editing.

Modified Capabilities

None.

Impact

• Affected code: wlgol.c, grid.c/h (read during ticks), possibly new simulation.c/h.
• Reuses existing input/config infrastructure; no new dependencies.
• Config defaults updated with simulation keys.