WindSim

See PROJECT_MASTER_PLAN.md for the long-term execution plan and the non-negotiable truthfulness rules.

What This Repo Is

WindSim is a browser-based 3D aerodynamic sandbox. The current build is a reduced-order simulator with live visualization, experiment controls, and telemetry. It is meant to make motion and airflow assumptions inspectable in real time.

It is not a CFD solver today.

Current State

What is already working in the repo:

• NEW: 2D Maker-and-Cell (MAC) Eulerian Grid CPU solver seamlessly replacing ambient wind when activated
• NEW: Full THREE.GLTFLoader importing for external meshes like .glb bounding-box autoscaling
• NEW: PBR lighting models rendered with THREE.RGBELoader running Studio HDR environment maps
• modular browser app split across index.html, windsim-entry.css, windsim-entry.js, windsim-data.js, windsim-physics.js, windsim-solvers.js, windsim-cfd.js, windsim-ui.js, windsim-workflows.js, windsim-textures.js, windsim-models.js, windsim-scene.js, and windsim-app.js
• object library with object-specific dimensions, mass assumptions, aero tuning, and contact behavior
• configurable wind speed, heading, elevation, turbulence, gusts, altitude, chamber size, and launch state
• reduced-order rigid-body motion with drag, lift, Magnus force, rotation, ground contact, wall contact, and telemetry
• mounted wind-tunnel mode, playback scrubbing, saved sweeps, run comparison, and flow-probe slices
• cinematic first-load landing flow with mode routing, recent-run restore, saved entry preferences, and seamless handoff into the live simulator
• CSV telemetry export and a small validation suite

What is still true about the codebase:

• The 2D CFD grid solver provides high-end fluid slices but operates only horizontally. Full 3D Navier-Stokes projection is currently bottlenecked by Javascript single-thread CPU limits.
• several models are heuristic or tuned for reduced-order behavior rather than derived from a solved flow field
• validation coverage is useful but still limited

Repo Layout

• index.html Browser shell, import map, simulator mount points, and script loading.
• windsim-entry.css Landing / entry visual system, transition styling, and responsive entry layout.
• windsim-entry.js React-based landing flow, motion system, mode routing, persisted entry preferences, and simulator handoff.
• windsim-data.js Static definitions: objects, surfaces, presets, validation cases, solver metadata.
• windsim-physics.js Reduced-order physics, wind sampling, contact handling, telemetry generation.
• windsim-solvers.js Solver registry and solver-facing app contract.
• windsim-ui.js DOM controls, panels, graph drawing, layout resizing, and UI synchronization.
• windsim-workflows.js Playback capture, timeline scrubbing, mounted sweep workflows, and saved experiment comparison.
• windsim-textures.js Canvas-based texture generation for surfaces and objects, color utilities, and seeded RNG.
• windsim-models.js 3D object visual construction, shape-to-mesh mapping, and material profiles.
• windsim-scene.js Rendering infrastructure, camera, lighting, particles, force arrows, trails, flow probes, and per-frame scene sync.
• windsim-app.js App bootstrap, scenario orchestration, input handling, and frame loop.

What The Project Is Not Yet

• not a chamber-wide pressure solver
• not a two-way coupled CFD system
• not a multi-solver research platform yet

Development Direction

Phase 1 (stabilize the reduced-order baseline) is complete. The current priority is solidifying the solver abstraction layer (Phase 2) and expanding research workflows (Phase 3). That means:

• formalising the solver interface so a second backend can plug in
• extending the plot set (Cl, Cm as separate channels)
• continuing to harden validation and truthfulness labeling

The new entry flow is part of that same direction: it improves first-load UX and routing without pretending the simulator underneath is more complete than it is.