69 lines
1.7 KiB
Go
69 lines
1.7 KiB
Go
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// CookieJar - A contestant's algorithm toolbox
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// Copyright (c) 2013 Peter Szilagyi. All rights reserved.
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//
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// CookieJar is dual licensed: use of this source code is governed by a BSD
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// license that can be found in the LICENSE file. Alternatively, the CookieJar
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// toolbox may be used in accordance with the terms and conditions contained
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// in a signed written agreement between you and the author(s).
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package geometry
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import (
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"math"
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)
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// Two dimensional point.
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type Point2 struct {
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X, Y float64
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}
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// Three dimensional point.
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type Point3 struct {
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X, Y, Z float64
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}
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// Allocates and returns a new 2D point.
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func NewPoint2(x, y float64) *Point2 {
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return &Point2{x, y}
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}
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// Allocates and returns a new 3D point.
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func NewPoint3(x, y, z float64) *Point3 {
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return &Point3{x, y, z}
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}
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// Calculates the distance between x and y.
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func (x *Point2) Dist(y *Point2) float64 {
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return math.Sqrt(x.DistSqr(y))
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}
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// Calculates the distance between x and y.
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func (x *Point3) Dist(y *Point3) float64 {
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return math.Sqrt(x.DistSqr(y))
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}
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// Calculates the squared distance between x and y.
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func (x *Point2) DistSqr(y *Point2) float64 {
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dx := x.X - y.X
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dy := x.Y - y.Y
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return dx*dx + dy*dy
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}
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// Calculates the squared distance between x and y.
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func (x *Point3) DistSqr(y *Point3) float64 {
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dx := x.X - y.X
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dy := x.Y - y.Y
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dz := x.Z - y.Z
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return dx*dx + dy*dy + dz*dz
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}
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// Returns whether two points are equal.
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func (x *Point2) Equal(y *Point2) bool {
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return math.Abs(x.X-y.X) < eps && math.Abs(x.Y-y.Y) < eps
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}
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// Returns whether two points are equal.
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func (x *Point3) Equal(y *Point3) bool {
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return math.Abs(x.X-y.X) < eps && math.Abs(x.Y-y.Y) < eps && math.Abs(x.Z-y.Z) < eps
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}
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