Class Frustum

constructor

• new Frustum(): Frustum

  Create a new Frustum instance.

  Returns Frustum

  Example

  const frustum = new pc.Frustum();
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planes

add

• add(other: Frustum): Frustum

  Expands this frustum to also contain another frustum. For each of the 6 planes, the plane that is further out (larger distance) is kept, creating a combined frustum that encompasses both. This is useful for multi-view rendering such as stereo XR where culling should keep objects visible in any view.

  Note: This method assumes both frustums have similar orientation (parallel views). This is valid for WebXR stereo rendering where eyes use parallel projection with only a horizontal offset, not toe-in convergence.

  Parameters

  • other: Frustum

    The other frustum to add.

  Returns Frustum

  Self for chaining.

clone

• clone(): Frustum

  Returns a clone of the specified frustum.

  Returns Frustum

  A duplicate frustum.

  Example

  const frustum = new pc.Frustum();
  const clone = frustum.clone();
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containsPoint

• containsPoint(point: Vec3): boolean

  Tests whether a point is inside the frustum. Note that points lying in a frustum plane are considered to be outside the frustum.

  Parameters

  • point: Vec3

    The point to test.

  Returns boolean

  True if the point is inside the frustum, false otherwise.

containsSphere

• containsSphere(sphere: BoundingSphere): number

  Tests whether a bounding sphere intersects the frustum. If the sphere is outside the frustum, zero is returned. If the sphere intersects the frustum, 1 is returned. If the sphere is completely inside the frustum, 2 is returned. Note that a sphere touching a frustum plane from the outside is considered to be outside the frustum.

  Parameters

  • sphere: BoundingSphere

    The sphere to test.

  Returns number

  0 if the bounding sphere is outside the frustum, 1 if it intersects the frustum and 2 if it is contained by the frustum.

copy

• copy(src: Frustum): Frustum

  Copies the contents of a source frustum to a destination frustum.

  Parameters

  • src: Frustum

    A source frustum to copy to the destination frustum.

  Returns Frustum

  Self for chaining.

  Example

  const src = entity.camera.frustum;
  const dst = new pc.Frustum();
  dst.copy(src);
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setFromMat4

• setFromMat4(matrix: Mat4): void

  Updates the frustum shape based on the supplied 4x4 matrix.

  Parameters

  • matrix: Mat4

    The matrix describing the shape of the frustum.

  Returns void

  Example

  // Create a perspective projection matrix
  const projection = new pc.Mat4();
  projection.setPerspective(45, 16 / 9, 1, 1000);
  
  // Create a frustum shape that is represented by the matrix
  const frustum = new pc.Frustum();
  frustum.setFromMat4(projection);
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