hexagons and grids coordinates conversions / published by https://github.com/dacr/code-examples-manager #5b018fd2-9875-4826-977d-8e9dd61876c7/2c28d2cdaaff53856cbdb4d43be9a20ed0236e06

algo-coordinates-hexagons-grids.sc

// summary : hexagons and grids coordinates conversions
// keywords : scala, coordinates, hexagons, conversions, @testable
// publish : gist
// authors : David Crosson
// license : Apache NON-AI License Version 2.0 (https://raw.githubusercontent.com/non-ai-licenses/non-ai-licenses/main/NON-AI-APACHE2)
// id : 5b018fd2-9875-4826-977d-8e9dd61876c7
// created-on : 2020-12-30T08:59:43Z
// managed-by : https://github.com/dacr/code-examples-manager
// run-with : scala-cli $file

// ---------------------
//> using scala  "3.3.0"
//> using dep "org.scalatest::scalatest:3.2.16"
//> using objectWrapper
// ---------------------

import org.scalatest._, flatspec._, matchers._
import scala.math._

trait HexaCoords {
  type Direction=String

  case class OffsetCoord(q:Int, r:Int)
  case class CubeCoord(x:Int, y:Int, z:Int) {
    def add(that:CubeCoord):CubeCoord = CubeCoord(x+that.x, y+that.y, z+that.z)
  }

  val moves:Map[Direction,CubeCoord] = Map(
    "n"  -> CubeCoord(+0,+0,-1),
    "s"  -> CubeCoord(+0,+0,+1),
    "e"  -> CubeCoord(+1,-1,+0),
    "w"  -> CubeCoord(-1,+1,+0),
    "nw" -> CubeCoord(+0,+1,+0),
    "se" -> CubeCoord(+0,-1,+0),
    "ne" -> CubeCoord(+1,+0,+0),
    "sw" -> CubeCoord(-1,+0,+0),
  )

  // convert odd-r offset to cube
  implicit def offset2cube(o:OffsetCoord):CubeCoord = {
    val x = o.q-(o.r - (o.r&1))/2
    val z = o.r
    val y = -x-z
    CubeCoord(x, y, z)
  }
  // convert cube to odd-r offset
  implicit def cube2offset(c:CubeCoord):OffsetCoord = {
    val q = c.x + (c.z-(c.z&1)) / 2
    val r = c.z
    OffsetCoord(q,r)
  }

  def distance(a:CubeCoord, b:CubeCoord):Int = {
    (abs(a.x - b.x) + abs(a.y - b.y) + abs(a.z - b.z)) / 2
  }

}


class HexaCoordsTest extends AnyFlatSpec with should.Matchers with HexaCoords  {
  override def suiteName: String = "TranscodingTest"

  "Encoding" should "encode x,y coordinate into single int value" in {
  }


}

org.scalatest.tools.Runner.main(Array("-oDF", "-s", classOf[HexaCoordsTest].getName))