Shape casting

A shape cast sweeps an entire shape along a direction and reports the first contact. It’s the swept-volume cousin of a raycast — perfect for probing the ground under a character’s feet, testing whether a body fits, or fat rays that won’t slip through cracks.

Drag to orbit

❚❚ Pause ↺ Reset

Run demo

Loading physics…

A sphere is cast straight down from the moving wireframe origin; the solid sphere shows where it first touches.

How it works

// castShape(shape, startPosition, startRotation, sweepDirection, options?)
const hit = world.castShape(
  Shape.sphere(0.4),
  [x, 4.5, 0],   // where the sweep starts
  undefined,     // start rotation (identity)
  [0, -6, 0],    // sweep direction + length: 6 units straight down
);

if (hit) {
  const landingY = 4.5 + -6 * hit.fraction; // start.y + direction.y * fraction
  hit.point;               // contact point on the surface
  hit.normal;              // surface normal
  hit.penetrationDepth;    // overlap if the shape started intersecting
}

castShape returns a ShapeCastHit with the same body/fraction/point/normal as a raycast, plus contactPointOnCaster, contactPointOnBody, and penetrationDepth for richer contact resolution.

Related

• Raycasting · Queries guide