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Build a navmesh and route a unit

curl -s -X POST http://localhost:3917/navmesh/generate \
  -H 'Content-Type: application/json' \
  -d '{"min_x":-50,"max_x":50,"min_z":-50,"max_z":50,"cell_size":1.0}'
# {"blocked_cells":0,"height":100,"ok":true,"total_cells":10000,"width":100}

curl -s -X POST http://localhost:3917/path/compute \
  -H 'Content-Type: application/json' -d '{"from":[0,0,0],"to":[10,0,5]}'
# {"count":10,"ok":true,"waypoints":[
#   [1.5,0.0,1.5],[2.5,0.0,2.5],[3.5,0.0,2.5],[4.5,0.0,3.5],[5.5,0.0,3.5],
#   [6.5,0.0,3.5],[7.5,0.0,4.5],[8.5,0.0,4.5],[9.5,0.0,4.5],[10.0,0.0,5.0]]}

curl -s -X POST http://localhost:3917/path/compute \
  -H 'Content-Type: application/json' -d '{"from":[-20,0,-20],"to":[20,0,20]}'
# {"count":40,"ok":true,"waypoints":[[-18.5,0.0,-18.5],...,[20.0,0.0,20.0]]}

curl -s -X POST http://localhost:3917/spawn \
  -H 'Content-Type: application/json' -d '{"position":[0,0,0]}'
# {"entity_id":1,"entity_generation":0}

curl -s -X POST http://localhost:3917/path/set \
  -H 'Content-Type: application/json' -d '{"entity_id":1,"target":[10,0,5],"speed":5.0}'
# {"ok":true,"message":"Set path goal for entity 1 to (10.0, 0.0, 5.0)"}

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Behavior and gotchas

• /path/set attaches the goal; whether the unit then moves depends on the project’s schedule and a usable navmesh. Following a path needs the euca-nav pathfinding_system (recompute the path when the goal is dirty) and steering_system (drive Velocity toward the next waypoint) in the project’s step schedule, plus a navmesh that actually contains a route. The example MOBA project served headless does schedule both systems — but with the default /navmesh/generate over its dense level geometry, the test cell is blocked, so /path/compute returns “No path found” and a unit set to a goal still doesn’t move:
  curl -s -X POST http://localhost:3917/path/set \
    -H 'Content-Type: application/json' -d '{"entity_id":106,"target":[10,0,10]}'
  # {"ok":true,"message":"Set path goal for entity 106 to (10.0, 0.0, 10.0)"}
  
  curl -s -X POST http://localhost:3917/step -H 'Content-Type: application/json' -d '{"ticks":30}'
  curl -s http://localhost:3917/entities/106
  # ..."transform":{"position":[0.0,0.0,0.0],...},"velocity":{"linear":[0.0,0.0,0.0],...}
  
  So /path/set returns {"ok":true,...} but the entity stays put. To see steering actually relocate a unit, generate a navmesh over an open region (min_x/max_x/min_z/max_z) so a route exists. Navmesh generation and /path/compute are self-contained and run synchronously regardless of the schedule.
• /navmesh/generate and /path/compute need no /step. Both run synchronously in the handler. Generation rasterizes colliders into the grid; compute reads the stored navmesh and runs A* immediately.
• The navmesh is static once built. It snapshots colliders at generation time and is not rebuilt when the world changes. Regenerate to refresh it — and regenerate before you compute paths, or /path/compute returns {"ok":false,"error":"No path found (no navmesh or blocked)"}.
• Waypoints are cell centers. With cell_size 1.0, interior waypoints land on x.5 coordinates; only the final waypoint is the exact requested target. A smaller cell_size yields finer paths and more cells.

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Endpoints

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Status

• Shipped — Navmesh generation from colliders, grid A* with Euclidean heuristic and line-of-sight smoothing, and the NavAgent/PathGoal steering components. All headless.
• Project-dependent — Following a path needs the euca-nav steering and pathfinding systems in the project’s step schedule and a navmesh that contains a route. The example MOBA project schedules both systems, but its dense level navmesh blocks the default test region, so /path/set attaches the goal yet the unit stays put; generate a navmesh over open ground (or run a project that does) to see steering relocate the agent. Navmesh generation and /path/compute work on any server.
• Partial — The navmesh is static once built (no automatic rebuild when colliders change; regenerate to refresh).