Struct ExactPoints 

pub struct ExactPoints { /* private fields */ }

A store of exact points and the exact predicates on them.

Orientation is counter-clockwise in (x, y) times the frame sign given to ExactPoints::with_frame_sign; a caller whose (x, y) are the coordinates of a mirrored frame passes Sign::Negative and reads “counter-clockwise” in its own frame.

Implementations

impl ExactPoints

pub fn nearest_on_segment( &self, point: PointId, start: PointId, end: PointId, ) -> GeomResult<Nearest>

Where the point of the segment start-end nearest to point lies: an end when the projection of point falls on or beyond it, else the foot of the perpendicular. InvalidInput when the ends are equal.

pub fn foot( &mut self, point: PointId, start: PointId, end: PointId, ) -> GeomResult<PointId>

The foot of the perpendicular from point to the line through start and end, an exact rational point. It lies on the segment exactly when ExactPoints::nearest_on_segment says Interior. InvalidInput when the ends are equal.

pub fn compare_distance( &self, a: PointId, b: PointId, length: f64, ) -> GeomResult<Ordering>

The order of the distance between a and b against length: Less when they are closer, Equal at exactly length. InvalidInput unless length is finite and not negative.

pub fn compare_line_distance( &self, point: PointId, start: PointId, end: PointId, length: f64, ) -> GeomResult<Ordering>

The order of the distance from point to the line through start and end against length: Less when it is closer, Equal at exactly length. InvalidInput unless length is finite and not negative, or when the ends are equal.

impl ExactPoints

pub fn new() -> Self

An empty store whose orientation is counter-clockwise in (x, y).

pub fn with_frame_sign(frame_sign: Sign) -> Self

An empty store whose orientation is frame_sign times the sense of (x, y). frame_sign must not be Sign::Zero.

pub fn frame_sign(&self) -> Sign

The frame sign the store was made with.

pub fn len(&self) -> usize

The number of points.

pub fn is_empty(&self) -> bool

Whether the store has no point.

pub fn push_flat(&mut self, flat: Point2) -> GeomResult<PointId>

A binary64 position.

pub fn push(&mut self, homogeneous: [Dyadic; 3]) -> GeomResult<PointId>

The point (x / w, y / w) of homogeneous coordinates with w != 0. A negative w is normalised. A point that is a binary64 position is stored as one, so it takes the fast path of the predicates.

pub fn push_hinted( &mut self, homogeneous: [Dyadic; 3], hints: [Option<f64>; 2], ) -> GeomResult<PointId>

Like ExactPoints::push, with a candidate value for each coordinate to try first, such as the coordinate of an edge that does not move in it.

pub fn flat(&self, point: PointId) -> Option<Point2>

The coordinates of a point that is a binary64 position (w = 1).

pub fn exact(&self, point: PointId) -> &[Dyadic; 3]

The exact homogeneous coordinates of a point, w > 0.

pub fn segment_crossing(&mut self, ends: [PointId; 4]) -> GeomResult<PointId>

The point where the segments ends[0]-ends[1] and ends[2]-ends[3] cross properly.

The lines L = a x b and the meeting point X = L1 x L2 have degrees 2 and (3, 3, 2) in the coordinates; w is made positive. When the point is a binary64 position it takes the fast path. Parallel segments have no crossing.

pub fn segment_parameter(&self, ends: [PointId; 4]) -> GeomResult<f64>

The parameter t along the first of two crossing segments (a to b and c to d, as in ExactPoints::segment_crossing) at which they cross: a + t (b - a). For output only.

pub fn orient(&self, a: PointId, b: PointId, c: PointId) -> GeomResult<Sign>

Exact orientation of a, b, c: positive when they turn counter-clockwise in the store’s sense (see ExactPoints).

pub fn compare( &self, a: PointId, b: PointId, axis: usize, ) -> GeomResult<Ordering>

Order of the coordinates of a and b along axis (0 = x, 1 = y). The stored axes, not the frame’s.

pub fn same(&self, a: PointId, b: PointId) -> GeomResult<bool>

Whether a and b are the same point.

pub fn lexicographic(&self, a: PointId, b: PointId) -> GeomResult<Ordering>

Order by x, then y.

pub fn bounds(&self, point: PointId) -> [f64; 4]

[x_lo, y_lo, x_hi, y_hi], a sound box of the point.

pub fn dominant(&self, a: PointId, b: PointId) -> GeomResult<usize>

The axis along which two distinct points of a line differ.

pub fn ordered( &self, a: PointId, b: PointId, axis: usize, ) -> GeomResult<(PointId, PointId)>

(low, high) of two points along axis.

pub fn strictly_between( &self, before: PointId, at: PointId, after: PointId, ) -> GeomResult<bool>

Whether collinear at lies strictly between before and after.

pub fn within_segment( &self, point: PointId, start: PointId, end: PointId, ) -> GeomResult<bool>

Whether collinear point lies on the closed segment start-end.

pub fn locate(&self, point: PointId, ring: &[PointId]) -> GeomResult<Location>

Where point lies relative to the closed ring: a crossing-number walk with exact orientation tests.

orient is in the frame’s sense and the y comparisons are in the stored axes. When the frame mirrors them the walk counts the crossings of the opposite ray, which is the winding number negated; only zero or nonzero is used.

pub fn ring_box(&self, ring: &[PointId]) -> RingBox

The boxes of a ring of exact points.

pub fn round(&self, point: PointId) -> GeomResult<Point2>

Each coordinate x / w and y / w rounded once to the nearest binary64 number, ties to even. Degenerate when one is beyond the binary64 range.

pub fn escalations(&self) -> usize

The number of predicate calls that left the interval filter for exact arithmetic. Not counted by the flat fast path.

Trait Implementations

impl Clone for ExactPoints

fn clone(&self) -> ExactPoints

Returns a duplicate of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Debug for ExactPoints

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl Default for ExactPoints

fn default() -> Self

Returns the “default value” for a type.