Class EllipsoidGeometry

Inheritance Relationships

Base Type

Class Documentation

class EllipsoidGeometry : public pfield::ObstacleGeometry

Geometry for an ellipsoid obstacle.

Defined by three semi-axes (a, b, c) along the principal axes. Supports PCA-rotated ellipsoids fitted to mesh geometry: axes holds the rotation from the obstacle frame to the principal-axis frame, and centroidOffset holds the mesh centroid displacement.

SDF: first-order approximation d ≈ f(p) / ||∇f(p)|| where f(p) = (px/a)² + (py/b)² + (pz/c)² - 1.

Public Functions

EllipsoidGeometry(double semiX, double semiY, double semiZ)

Constructs an axis-aligned EllipsoidGeometry centered at the origin.

Parameters:

  • semiX – Semi-axis along X (must be > 0).

  • semiY – Semi-axis along Y (must be > 0).

  • semiZ – Semi-axis along Z (must be > 0).

EllipsoidGeometry(double semiX, double semiY, double semiZ, const Eigen::Matrix3d &axes, const Eigen::Vector3d &centroidOffset)

Constructs a PCA-rotated EllipsoidGeometry.

Parameters:

  • semiX – Semi-axis along the PCA X principal axis.

  • semiY – Semi-axis along the PCA Y principal axis.

  • semiZ – Semi-axis along the PCA Z principal axis.

  • axes – Rotation from obstacle frame to PCA frame (columns are principal axes).

  • centroidOffset – Offset from the collision-origin to the ellipsoid center, expressed in the obstacle’s local frame.

virtual ObstacleType getType() const override

Returns the ObstacleType discriminator for this geometry.

virtual std::vector<double> asVector() const override

Returns a vector of the geometry’s defining parameters.

The vector layout is type-specific: Sphere → {radius} Box → {length, width, height} Cylinder → {radius, height} Ellipsoid → {semi_x, semi_y, semi_z} Capsule → {radius, height} Mesh → {length, width, height} (bounding-box dims or zeros)

virtual Eigen::Vector3d halfDimensions(const Eigen::Vector3d &meshScale) const override

Returns the half-dimensions of the obstacle’s axis-aligned bounding box.

Used for broad-phase influence-zone checks.

Parameters:

meshScale – Scale of the mesh resource (used only by MeshGeometry; ignored by all other types).

virtual void computeSignedDistanceAndNormal(const Eigen::Vector3d &localPoint, const Eigen::Quaterniond &obstacleOrientation, double &signedDistance, Eigen::Vector3d &normal) const override

Computes the signed distance and outward surface normal from a point expressed in the obstacle’s local frame.

The caller is responsible for transforming the world-frame query point into the obstacle’s local frame before calling this method.

Parameters:

  • localPoint – [in] Query point in the obstacle’s local frame.

  • obstacleOrientation – [in] World-frame orientation of the obstacle (quaternion), used to rotate the computed normal back to world coordinates.

  • signedDistance – [out] Signed distance to the obstacle surface (negative if inside, positive if outside).

  • normal – [out] Outward unit normal in world coordinates at the closest surface point.

virtual std::shared_ptr<coal::CollisionGeometry> buildCoalGeometry(const Eigen::Vector3d &obstaclePosition, const Eigen::Quaterniond &obstacleOrientation, coal::Transform3s &coalTransform) const override

Builds the Coal collision geometry for this obstacle.

The returned shared_ptr is used to construct a coal::CollisionObject. The caller is responsible for supplying the correct world-frame transform.

Parameters:

  • obstaclePosition – World-frame position of the obstacle origin.

  • obstacleOrientation – World-frame orientation of the obstacle.

  • coalTransform – [out] The Coal transform that should be passed to coal::CollisionObject together with the returned geometry. For most types this equals the obstacle pose, but OBB-fitted shapes (Box, Capsule) may shift and rotate it to the OBB center.

Returns:

Shared pointer to the Coal collision geometry.

virtual coal::Transform3s computeUpdatedCoalTransform(const Eigen::Vector3d &obstaclePosition, const Eigen::Quaterniond &obstacleOrientation) const override

Computes the world-frame Coal transform to use when updating a cached collision object’s pose.

For most types this simply encodes (obstaclePosition, obstacleOrientation). OBB-fitted types (Box, Capsule) adjust for the centroid offset and PCA rotation baked into the Coal object at construction time.

Parameters:

  • obstaclePosition – New world-frame position of the obstacle.

  • obstacleOrientation – New world-frame orientation of the obstacle.

Returns:

The Coal transform to apply to the cached collision object.

virtual bool operator==(const ObstacleGeometry &other) const override

Equality comparison — only types with the same concrete class and parameters are equal.

virtual std::unique_ptr<ObstacleGeometry> clone() const override

Deep-copy factory, so PotentialFieldObstacle can clone its geometry.

Public Members

double semiX

Semi-axis along principal X.

double semiY

Semi-axis along principal Y.

double semiZ

Semi-axis along principal Z.

Eigen::Matrix3d axes

PCA rotation (identity if axis-aligned).

Eigen::Vector3d centroidOffset

Centroid offset (zero if centered).

std::string sourceMeshResource

Mesh URI from which this ellipsoid was fitted (empty if not mesh-derived).

Eigen::Vector3d sourceMeshScale = Eigen::Vector3d::Ones()

Mesh scale corresponding to sourceMeshResource.