vector

Vector

A 3D and 2D Vector Library, In Golang

go get git.red-green.com/david/vector

Quickstart

package main

import (
    "fmt"
    vec "git.red-green.com/david/vector"
)

func main() {
    // 3D
    var v vec.Vec = vec.NewVec3()
    fmt.Printf("Hello v, %s\r\n", v)
    // Hello v, (0, 0, 0)

    // 2D
    var v2 vec.Vec = vec.NewVec2(2, -2)
    fmt.Printf("Oh, Hi v2, %s\r\n", v2)
    // Oh, Hi v2, (2, -2)

    // Or auto detect
    // 3D
    var v3 vec.Vec = vec.NewVec()
    fmt.Printf("v3 = %s\r\n", v3)
    // v3 = (0, 0, 0)
    // 2D
    var v4 vec.Vec = vec.NewVec(2, -2)
    fmt.Printf("v4 = %s\r\n", v4)
    // v4 = (2, -2)
}

Library Info

Types

• vector.Vec interface/generic of *vector.Vec2 or *vector.Vec3
• vector.Vec2 struct { X int64, Y int64 }
• vector.Vec3 struct { X int64, Y int64, Z int64 }

Many methods will return the generic vector.Vec instead of the direct Vec2 or Vec3 to satisfy the Vec interface (Use Is2D or Is3D to determine Vec2 or Vec3 and convert to *Vec2 or *Vec3 from there, i.e. var v1 *vec.Vec2 = v.(*vec.Vec2) or var v1 *vec.Vec3 = v.(*vec.Vec3))

Constructor (Generic/Auto)

• vector.NewVec(...int64) vector.Vec
  • 0 to 1 values will result in nil (Use vector.NewVec2 or vector.NewVec3 to obtain a zeroed Vec)
  • 2 values will result in a *vector.Vec2 with X and Y
  • 3+ values will result in a *vector.Vec3 with X, Y and Z
  • 4 or more values are not used
• vector.VecFrom(vector.Vec) vector.Vec
  • A nil will result in nil (vector.Vec2From or vector.Vec3From will make zeroed copies instead)
  • A *vector.Vec2 will result in a *vector.Vec2 with X and Y copied
  • A *vector.Vec3 will result in a *vector.Vec3 with X, Y and Z copied
• vector.VecString(string) (Vec, error)
  • Given a string of a vector (You can use Vec2.String() or Vec3.String() to make this quickly)
  • string requirements:
    • Must start with a ( and end with a ) (missing parentheses)
    • Must contain from 1 to 2 , (invalid comma count: expected 1-2 got #)
      • 1 comma for a 2D vector.Vec2 (X, Y)
      • 2 commas for a 3D vector.Vec3 (X, Y, Z)
    • vector.Vec2String(string) (Vec, error) will expect the string to make a valid Vec2 rather than a Vec3 (A Vec3 will be converted)
    • vector.Vec3String(string) (Vec, error) will expect the string to make a valid Vec3 rather than a Vec2 (A Vec2 will be converted)