Terrain Primitives

Terrain primitives let agents reason about land shape before generating buildings.

Source Grouping

site main:
  terrain:
    existing:
      representation contours
      source survey.existing_topo

      contours:
        c_420:
          elevation 420000mm
          polyline [(0, 10000), (12000, 11000), (24000, 9000)]

      breaklines:
        ridge_01:
          polyline [(5000, 5000), (18000, 9000)]

Paths

Primitive	Path
Terrain surface	site.main.terrain.existing
Terrain point	site.main.terrain.existing.points.pt_001
Contour line	site.main.terrain.existing.contours.c_420
Breakline	site.main.terrain.existing.breaklines.ridge_01
Slope region	site.main.terrain.existing.slope_regions.sr_001
Drainage path	site.main.terrain.existing.drainage_paths.dp_001
Grading region	site.main.terrain.proposed.grading.regions.gr_001
Cut/fill metric	site.main.terrain.proposed.metrics.cut_fill

Required Fields

Field	Required	Notes
representation	yes	tin, grid, contours, or hybrid
source	recommended	Survey, DEM, LandXML, manual
points	conditional	Required for point/TIN workflows
contours	conditional	Required for contour workflows
breaklines	optional	Improves terrain fidelity
coordinate_system	inherited	From site unless overridden

Operations

Operation	Purpose
createTerrainSurface	Create a terrain surface
contourToTerrain	Derive surface from contours
addTerrainPoint	Add survey/elevation point
addBreakline	Add terrain discontinuity or feature line
calculateSlopeRegions	Derive slope regions
calculateDrainagePaths	Derive drainage paths
gradeRegion	Create proposed terrain modifications
calculateCutFill	Estimate earthwork delta

Evals

Eval	Typical target
terrain.valid_surface	site.main.terrain.existing
terrain.contour_elevation_order	site.main.terrain.existing.contours
terrain.slope_threshold	site.main.terrain.existing.slope_regions
terrain.access_slope	site.main.parcels.pcl_001.access
terrain.drainage_conflict	site.main.terrain.existing.drainage_paths
terrain.cut_fill_limit	site.main.terrain.proposed.metrics.cut_fill