Struct Tolerance
- Namespace
- GeometryHelper
- Assembly
- GeometryHelper.dll
Tolerance used for geometric comparisons.
Every comparison in this library that can be affected by floating point error
takes a tolerance, and every such method has an overload without one that reads
Global. Neither library compares coordinates with ==.
Global is one setting shared by both libraries. Changing it for a drawing in the plane changes it for a model in space as well.
Make one with a constructor, or take Default or Global. new Tolerance() is
not the default tolerance: like default(Tolerance) it runs no constructor and has every threshold at 0,
under which only an exact match is equal and a face out of flat by rounding alone is refused.
public readonly struct Tolerance : IEquatable<Tolerance>- Implements
- Inherited Members
Constructors
- Tolerance(double, double)
Initializes a tolerance instance with thresholds for points and vectors, using the default angular and planar thresholds.
- Tolerance(double, double, double)
Initializes a tolerance instance with thresholds for points, vectors and angles. The planar threshold follows
equalPoint, since coplanarity is measured as a distance.
- Tolerance(double, double, double, double)
Initializes a tolerance instance with thresholds for points, vectors, angles and coplanarity.
Fields
- DefaultEqualAngleRad
Default tolerance when comparing angles for parallelism / perpendicularity, in radians (1 degree in radians).
- DefaultEqualPlanar
Default distance threshold for deciding whether a set of points lies on a common plane: a hundredth of a millimetre in a model in millimetres, the same as DefaultEqualPoint.
- DefaultEqualPoint
Default tolerance when comparing points: a hundredth of a millimetre in a model in millimetres.
- DefaultEqualVector
Default tolerance when comparing vectors.
Properties
- Default
Gets the default tolerance: DefaultEqualPoint, DefaultEqualVector, DefaultEqualAngleRad and DefaultEqualPlanar together.
- EqualAngleRad
Angular threshold to consider two directions / lines as parallel or perpendicular, in radians.
- EqualPlanar
Distance threshold to consider a point as lying on a plane, in drawing units.
This is separate from EqualPoint because coplanarity is checked far from the reference point: a polygon several metres across turns a hundredth of a degree of tilt into a deviation of nearly a millimetre, so the threshold that decides whether two points coincide is the wrong one to decide whether a face is flat.
- EqualPoint
Distance threshold to consider two points as coincident, in drawing units.
- EqualVector
Threshold to consider two vectors as equal.
Methods
- Equals(Tolerance)
Compares two tolerance instances exactly.
- Equals(object)
Compares with an arbitrary object.
- GetHashCode()
Hash code built from thresholds.
- ToString()
Represents the thresholds as a string.
- Use(Tolerance)
Makes a tolerance the one every overload without a tolerance uses on this thread, until the returned scope is disposed.
Operators
- operator ==(Tolerance, Tolerance)
Compares two Tolerance instances for equality.
- operator !=(Tolerance, Tolerance)
Compares two Tolerance instances for inequality.