Fallen Tribes - Task Checklist

Immediate TODO (Current Drag System)

Phase 1: Core Drag System Polish ✅

• Test current gold/blue hologram drag system thoroughly
• Verify hologram material switching (gold → blue on release)
• Ensure line drawing works correctly between ship and hologram
• Test that only one hologram exists at a time
• Verify ship stays in original position during drag
• Remove cube from scene

Phase 2: UI Button System

• Create "Move" button component
  • Spawn button when ship is selected
  • Position button relative to ship's world position
  • World-to-screen coordinate transformation
  • Raycasting for button clicks
• Create "Coast" button component
  • Spawn button when hologram exists
  • Position button relative to ship
  • Clicking removes hologram
• Button hover states
• Button styling (matching HTML prototype) (TODO: later)

Phase 3: Outline System ✅

• Research Bevy 0.17 outline rendering approaches
  • Option A: Post-processing outline shader
  • Option B: Duplicate mesh with inverted normals + scaled
  • Option C: Third-party Bevy outline plugin
• Implement blue outline on hover
• Implement darker blue outline on selection (persists)
• Ensure outlines work with OBJ models loaded via bevy_obj

Phase 4: Multi-Ship Selection & Estimated Move System ✅

• Add second ship to test multi-ship selection
• Create EstimatedMove struct (position + rotation)
• Track estimated_move per ship in ShipController
• Click ship → select it (darker outline)
• Click elsewhere → deselect ship (via observers)
• Multiple ships: only one selected at a time
• Each ship tracks own hologram/estimated move independently
• Visual feedback for selected vs unselected state
• BONUS: Direct click-and-drag on ships (no Move button needed!)
• BONUS: Mesh-accurate picking and hover detection with observers

Phase 5: Refactor Drag to Use Move Button

• Remove drag-from-ship behavior
• Implement drag-from-Move-button behavior
• Spawn gold hologram when dragging from Move button
• Hologram follows cursor during drag
• Hologram turns blue on release
• Line still draws from ship to hologram

---

Future TODO (Based on HTML Prototype Features)

Turn-Based Movement System

• Implement turn state machine
  • Planning phase (click targets, see preview)
  • Execution phase (animate movement)
  • End turn button functionality
• Movement validation
  • Reachability calculation grid
  • Green dots for reachable positions
  • Red dots for unreachable positions
• Path preview with Bezier curves
• Display velocity vectors during planning

Physics Simulation

• Newtonian physics integration
  • Initial velocity (vx, vy)
  • Acceleration/deceleration
  • Max speed constraints
• Coupled flight mode
  • Main thruster acceleration
  • Automatic deceleration
  • Turn rate limits (°/s)
• Decoupled flight mode
  • Independent thruster control (forward, backward, left, right)
  • Target rotation control
  • Maneuvering thrusters
• Gravity wells
  • Gravitational bodies with mass/radius
  • Influence radius visualization
  • Gravity acceleration calculations
  • Bezier path modifications from gravity

Movement Animation

• Animate ship movement along planned path
  • Bezier curve interpolation
  • Rotation animation
  • Velocity changes over time
• Ship state updates after movement
  • Update position
  • Update velocity
  • Update heading
• Movement history tracking
• Replay system for past moves

UI & Controls

• Camera pan controls
  • Mouse right-click drag
  • Touch hold to pan
• Camera zoom controls
  • Mouse wheel zoom
  • Pinch to zoom (touch)
  • Zoom centered on mouse position
• Control panels
  • Left sidebar: flight mode & physics parameters
  • Right sidebar: help & legend
  • Collapsible sidebars
  • Bottom button bar (Coast, End Turn, Replay)
• Status display
  • Current zoom level
  • Reachability status
  • Turn state

Strategic Depth

• Reachability calculations
  • Grid-based reachability analysis
  • Path validation
  • Time-limited movement
• Movement cost visualization
  • Speed magnitude display
  • Segment time labels
  • Thrust indicators (decoupled mode)
• Multiple ship coordination
  • Select different ships
  • Individual movement planning
  • Turn order management

Visual Polish

• Ship rendering
  • Blue ship (current position, with glow)
  • Gold ship (dragging preview)
  • Orange ship (destination preview)
  • Ghost ships along path
• Path visualization
  • Smooth Bezier curves
  • Fading opacity along path
  • Velocity vector arrows
  • Segment markers with time labels
• Grid rendering
  • Dynamic grid density
  • Reachability overlay
  • Coordinate system
• Gravity well visualization
  • Colored influence radius rings
  • Acceleration labels
  • Gradient field visualization

Advanced Features

• Collision detection
  • Ship-to-ship collisions
  • Ship-to-gravity-well collisions
• Obstacles/terrain
• Fog of war
• Multiple teams/factions
• Combat system
• Resource management

---

Technical Debt & Optimization

• Performance profiling
• Asset loading optimization
• Shader compilation caching
• Entity pooling for holograms
• Efficient reachability grid calculation
• LOD system for distant ships

---

Documentation

• Update README.md with current progress
• Document ship state machine
• Document physics simulation parameters
• Add code comments for complex systems
• Create user guide for controls