Building the Alaska Terrain Analytics Engine
Slope, watersheds, elevation bands, and avalanche terrain—the intelligence layer that makes TrueTopo maps actionable in the field.
Topographic maps show elevation. But terrain analytics answer real questions: Is this slope too steep for a snowmachine? Which direction does water flow? Where does avalanche terrain start?
We're building the Alaska Terrain Analytics Engine inside TrueTopo—a client-side engine that computes slope, aspect, watershed boundaries, and avalanche-terrain classification from 3DEP elevation data.
The Problem
Most mapping apps display contours and call it a day. Contours are useful for navigation, but they don't tell you:
- Steepness for route planning
- Drainage basins for hunting or fishing
- Avalanche start zones for winter travel
- Line-of-sight for communications
The Approach
TrueTopo runs terrain analytics in the browser using Web Workers and streaming elevation tiles. No server round-trips. Results are cached and available offline.
Current capabilities:
- Slope shading (0–90°)
- Aspect (compass direction of slope face)
- Watershed delineation (experimental)
- Elevation profiles along routes
Roadmap:
- Avalanche terrain classification (simple/complex)
- Solar exposure and shadow maps
- Hydrologic flow accumulation
- Viewshed analysis
Why Client-Side
Alaska is big. Processing terrain for the entire state would require petabytes of precomputed rasters. By computing on-demand for the visible viewport, we keep data size manageable and latency low—especially critical when you're in the field with a spotty connection.