Spancraft

A Minecraft-inspired voxel world builder with power line engineering tools, built with Three.js.

Play Spancraft on GitHub Pages

Features

Building & Exploration

• Voxel-based world generation with varied terrain
• First-person controls (WASD + Mouse)
• Flying mode - Press F to toggle creative flight
• Multiple block types: Dirt, Stone, Wood, Cobblestone, Brick, Grass
• Utility Poles - Tall vertical structures for power line construction
• Block placement and removal (Right click / Left click)
• Jumping, collision detection, and realistic physics
• Dynamic lighting and shadows

Power Line Engineering

• Utility Pole System - Two types of pole blocks for building power line structures
  • Wood Poles (key 7) - Traditional utility poles with brown wood texture
  • Metal Poles (key 8) - Modern steel poles with metallic finish
  • Single-block height - stack vertically to build tall structures
  • Thin profile (0.3 blocks wide) for realistic appearance
  • Place and remove like regular blocks
• Conductor Wire System (key 9) - Realistic power line spans with true catenary physics
  • Click on first pole, then click on second pole to create wire connection
  • Wires exhibit natural catenary sag (hyperbolic cosine curve)
  • Sag amount automatically calculated at 10% of horizontal span length
  • Physics-based curve uses Newton-Raphson solver for tension parameter
  • Red glow indicates clearance violation (wire intersecting terrain/poles)
  • Walkable wires - player passes through conductor without collision

Controls

Movement

• WASD or Arrow Keys - Move around
• Mouse - Look around (click to lock pointer)
• Space - Jump (or fly up when in flying mode)
• Shift - Fly down (when in flying mode)
• F - Toggle flying mode

Building

• Left Click - Remove block/pole/wire
• Right Click - Place block/pole or select pole for wiring
• Scroll Wheel - Select block type

Utility Poles

• Scroll to select wood poles or metal poles
• Right-click to place pole blocks (single block height)
• Stack poles vertically by placing on top of each other
• Left-click to remove individual pole blocks
• Thin profile (0.3 blocks) for realistic appearance

Conductor Wires

• Scroll to select conductor wire mode
• Right-click first pole to start wire connection
• Right-click second pole to complete connection
• Wire automatically forms realistic catenary curve between poles
• Red glow warns of clearance violations
• Left-click wire to remove connection

How to Run

1. Run python3 -m http.server in the root directory
2. Open http://localhost:8000 in your browser
3. Click to lock the pointer and start building!