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The mesh and collider must agree.

This route turns Rapier's heightfield boundary into a terrain laboratory: one sampled function drives the visible grid and the physics matrix, profile edits rebuild the fixed collider, and falling bodies make the contact result visible.

Initializing Preparing renderer

Preparing the sampled terrain, heightfield body, and dynamic test bodies...

physics: -
samples: -
bodies: -
terrain: -
profile: -
height: -
selected: -
fps: -

Heightfield controlsbody 1

terrain profile

height scale

wireframe terrain show Rapier colliders

Select a body to inspect its shared terrain height and physics lifecycle.

Heightfield contractofficial API boundary

generateHeight(...)sample one terrain function

BufferGeometry.positionwrite visible row-major grid

physics.addHeightfield(...)register fixed collider

Float32Array[column * n + row]write Rapier column-major matrix

physics.addMesh(...)register falling bodies

physics.removeMesh(...)remove dynamic body

world.removeRigidBody(...)replace terrain body

new RapierHelper(world)inspect collider topology

The visible grid indexes samples as row then column. Rapier's 3D heightfield expects the same samples as a column-major matrix, so the lab writes both views from one function and makes profile rebuilds replace the fixed body.

Selected bodyactive

shape-

position-

terrain height-

lifecycle-

Rapier is loading. The fixed heightfield and dynamic body map become available after WASM initialization.

Based on the official Rapier terrain example, RapierPhysics docs, and heightfield collider API. The CPU fallback approximates terrain contact and does not claim full heightfield parity.

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