MOOSE/Moose Development/Moose/Core/Point.lua

--- This module contains the POINT classes.
-- 
-- 1) @{Core.Point#POINT_VEC3} class, extends @{Core.Base#BASE}
-- ==================================================
-- The @{Core.Point#POINT_VEC3} class defines a 3D point in the simulator.
-- 
-- **Important Note:** Most of the functions in this section were taken from MIST, and reworked to OO concepts.
-- In order to keep the credibility of the the author, I want to emphasize that the of the MIST framework was created by Grimes, who you can find on the Eagle Dynamics Forums.
-- 
-- 1.1) POINT_VEC3 constructor
-- ---------------------------
-- A new POINT_VEC3 instance can be created with:
-- 
--  * @{#POINT_VEC3.New}(): a 3D point.
--  * @{#POINT_VEC3.NewFromVec3}(): a 3D point created from a @{Dcs.DCSTypes#Vec3}.
--  
--
-- 2) @{Core.Point#POINT_VEC2} class, extends @{Core.Point#POINT_VEC3}
-- =========================================================
-- The @{Core.Point#POINT_VEC2} class defines a 2D point in the simulator. The height coordinate (if needed) will be the land height + an optional added height specified.
-- 
-- 2.1) POINT_VEC2 constructor
-- ---------------------------
-- A new POINT_VEC2 instance can be created with:
-- 
--  * @{#POINT_VEC2.New}(): a 2D point, taking an additional height parameter.
--  * @{#POINT_VEC2.NewFromVec2}(): a 2D point created from a @{Dcs.DCSTypes#Vec2}.
-- 
-- ===
-- 
-- **API CHANGE HISTORY**
-- ======================
-- 
-- The underlying change log documents the API changes. Please read this carefully. The following notation is used:
-- 
--   * **Added** parts are expressed in bold type face.
--   * _Removed_ parts are expressed in italic type face.
-- 
-- Hereby the change log:
-- 
-- 2016-08-12: POINT_VEC3:**Translate( Distance, Angle )** added.
-- 
-- 2016-08-06: Made PointVec3 and Vec3, PointVec2 and Vec2 terminology used in the code consistent.
-- 
--   * Replaced method _Point_Vec3() to **Vec3**() where the code manages a Vec3. Replaced all references to the method.
--   * Replaced method _Point_Vec2() to **Vec2**() where the code manages a Vec2. Replaced all references to the method.
--   * Replaced method Random_Point_Vec3() to **RandomVec3**() where the code manages a Vec3. Replaced all references to the method.
-- .
-- ===
--  
-- ### Authors: 
-- 
--   * FlightControl : Design & Programming
--   
-- ### Contributions: 
-- 
-- @module Point

--- The POINT_VEC3 class
-- @type POINT_VEC3
-- @extends Core.Base#BASE
-- @field #number x The x coordinate in 3D space.
-- @field #number y The y coordinate in 3D space.
-- @field #number z The z coordiante in 3D space.
-- @field Utilities.Utils#SMOKECOLOR SmokeColor
-- @field Utilities.Utils#FLARECOLOR FlareColor
-- @field #POINT_VEC3.RoutePointAltType RoutePointAltType
-- @field #POINT_VEC3.RoutePointType RoutePointType
-- @field #POINT_VEC3.RoutePointAction RoutePointAction
POINT_VEC3 = {
  ClassName = "POINT_VEC3",
  Metric = true,
  RoutePointAltType = {
    BARO = "BARO",
  },
  RoutePointType = {
    TakeOffParking = "TakeOffParking",
    TurningPoint = "Turning Point",
  },
  RoutePointAction = {
    FromParkingArea = "From Parking Area",
    TurningPoint = "Turning Point",
  },
}

--- The POINT_VEC2 class
-- @type POINT_VEC2
-- @extends #POINT_VEC3
-- @field Dcs.DCSTypes#Distance x The x coordinate in meters.
-- @field Dcs.DCSTypes#Distance y the y coordinate in meters.
POINT_VEC2 = {
  ClassName = "POINT_VEC2",
}


do -- POINT_VEC3

--- RoutePoint AltTypes
-- @type POINT_VEC3.RoutePointAltType
-- @field BARO "BARO"

--- RoutePoint Types
-- @type POINT_VEC3.RoutePointType
-- @field TakeOffParking "TakeOffParking"
-- @field TurningPoint "Turning Point"

--- RoutePoint Actions
-- @type POINT_VEC3.RoutePointAction
-- @field FromParkingArea "From Parking Area"
-- @field TurningPoint "Turning Point"

-- Constructor.
  
--- Create a new POINT_VEC3 object.
-- @param #POINT_VEC3 self
-- @param Dcs.DCSTypes#Distance x The x coordinate of the Vec3 point, pointing to the North.
-- @param Dcs.DCSTypes#Distance y The y coordinate of the Vec3 point, pointing Upwards.
-- @param Dcs.DCSTypes#Distance z The z coordinate of the Vec3 point, pointing to the Right.
-- @return Core.Point#POINT_VEC3 self
function POINT_VEC3:New( x, y, z )

  local self = BASE:Inherit( self, BASE:New() )
  self.x = x
  self.y = y
  self.z = z
  
  return self
end

--- Create a new POINT_VEC3 object from  Vec3 coordinates.
-- @param #POINT_VEC3 self
-- @param Dcs.DCSTypes#Vec3 Vec3 The Vec3 point.
-- @return Core.Point#POINT_VEC3 self
function POINT_VEC3:NewFromVec3( Vec3 )

  self = self:New( Vec3.x, Vec3.y, Vec3.z )
  self:F2( self )
  return self
end


--- Return the coordinates of the POINT_VEC3 in Vec3 format.
-- @param #POINT_VEC3 self
-- @return Dcs.DCSTypes#Vec3 The Vec3 coodinate.
function POINT_VEC3:GetVec3()
  return { x = self.x, y = self.y, z = self.z }
end

--- Return the coordinates of the POINT_VEC3 in Vec2 format.
-- @param #POINT_VEC3 self
-- @return Dcs.DCSTypes#Vec2 The Vec2 coodinate.
function POINT_VEC3:GetVec2()
  return { x = self.x, y = self.z }
end


--- Return the x coordinate of the POINT_VEC3.
-- @param #POINT_VEC3 self
-- @return #number The x coodinate.
function POINT_VEC3:GetX()
  return self.x
end

--- Return the y coordinate of the POINT_VEC3.
-- @param #POINT_VEC3 self
-- @return #number The y coodinate.
function POINT_VEC3:GetY()
  return self.y
end

--- Return the z coordinate of the POINT_VEC3.
-- @param #POINT_VEC3 self
-- @return #number The z coodinate.
function POINT_VEC3:GetZ()
  return self.z
end

--- Set the x coordinate of the POINT_VEC3.
-- @param #number x The x coordinate.
function POINT_VEC3:SetX( x )
  self.x = x
end

--- Set the y coordinate of the POINT_VEC3.
-- @param #number y The y coordinate.
function POINT_VEC3:SetY( y )
  self.y = y
end

--- Set the z coordinate of the POINT_VEC3.
-- @param #number z The z coordinate.
function POINT_VEC3:SetZ( z )
  self.z = z
end

--- Return a random Vec2 within an Outer Radius and optionally NOT within an Inner Radius of the POINT_VEC3.
-- @param #POINT_VEC3 self
-- @param Dcs.DCSTypes#Distance OuterRadius
-- @param Dcs.DCSTypes#Distance InnerRadius
-- @return Dcs.DCSTypes#Vec2 Vec2
function POINT_VEC3:GetRandomVec2InRadius( OuterRadius, InnerRadius )
  self:F2( { OuterRadius, InnerRadius } )

  local Theta = 2 * math.pi * math.random()
  local Radials = math.random() + math.random()
  if Radials > 1 then
    Radials = 2 - Radials
  end

  local RadialMultiplier
  if InnerRadius and InnerRadius <= OuterRadius then
    RadialMultiplier = ( OuterRadius - InnerRadius ) * Radials + InnerRadius
  else
    RadialMultiplier = OuterRadius * Radials
  end

  local RandomVec2
  if OuterRadius > 0 then
    RandomVec2 = { x = math.cos( Theta ) * RadialMultiplier + self:GetX(), y = math.sin( Theta ) * RadialMultiplier + self:GetZ() }
  else
    RandomVec2 = { x = self:GetX(), y = self:GetZ() }
  end
  
  return RandomVec2
end

--- Return a random POINT_VEC2 within an Outer Radius and optionally NOT within an Inner Radius of the POINT_VEC3.
-- @param #POINT_VEC3 self
-- @param Dcs.DCSTypes#Distance OuterRadius
-- @param Dcs.DCSTypes#Distance InnerRadius
-- @return #POINT_VEC2
function POINT_VEC3:GetRandomPointVec2InRadius( OuterRadius, InnerRadius )
  self:F2( { OuterRadius, InnerRadius } )
  
  return POINT_VEC2:NewFromVec2( self:GetRandomVec2InRadius( OuterRadius, InnerRadius ) )
end

--- Return a random Vec3 within an Outer Radius and optionally NOT within an Inner Radius of the POINT_VEC3.
-- @param #POINT_VEC3 self
-- @param Dcs.DCSTypes#Distance OuterRadius
-- @param Dcs.DCSTypes#Distance InnerRadius
-- @return Dcs.DCSTypes#Vec3 Vec3
function POINT_VEC3:GetRandomVec3InRadius( OuterRadius, InnerRadius )

  local RandomVec2 = self:GetRandomVec2InRadius( OuterRadius, InnerRadius )
  local y = self:GetY() + math.random( InnerRadius, OuterRadius )
  local RandomVec3 = { x = RandomVec2.x, y = y, z = RandomVec2.z }

  return RandomVec3
end

--- Return a random POINT_VEC3 within an Outer Radius and optionally NOT within an Inner Radius of the POINT_VEC3.
-- @param #POINT_VEC3 self
-- @param Dcs.DCSTypes#Distance OuterRadius
-- @param Dcs.DCSTypes#Distance InnerRadius
-- @return #POINT_VEC3
function POINT_VEC3:GetRandomPointVec3InRadius( OuterRadius, InnerRadius )

  return POINT_VEC3:NewFromVec3( self:GetRandomVec3InRadius( OuterRadius, InnerRadius ) )
end


--- Return a direction vector Vec3 from POINT_VEC3 to the POINT_VEC3.
-- @param #POINT_VEC3 self
-- @param #POINT_VEC3 TargetPointVec3 The target POINT_VEC3.
-- @return Dcs.DCSTypes#Vec3 DirectionVec3 The direction vector in Vec3 format.
function POINT_VEC3:GetDirectionVec3( TargetPointVec3 )
  return { x = TargetPointVec3:GetX() - self:GetX(), y = TargetPointVec3:GetY() - self:GetY(), z = TargetPointVec3:GetZ() - self:GetZ() }
end

--- Get a correction in radians of the real magnetic north of the POINT_VEC3.
-- @param #POINT_VEC3 self
-- @return #number CorrectionRadians The correction in radians.
function POINT_VEC3:GetNorthCorrectionRadians()
  local TargetVec3 = self:GetVec3()
  local lat, lon = coord.LOtoLL(TargetVec3)
  local north_posit = coord.LLtoLO(lat + 1, lon)
  return math.atan2( north_posit.z - TargetVec3.z, north_posit.x - TargetVec3.x )
end


--- Return a direction in radians from the POINT_VEC3 using a direction vector in Vec3 format.
-- @param #POINT_VEC3 self
-- @param Dcs.DCSTypes#Vec3 DirectionVec3 The direction vector in Vec3 format.
-- @return #number DirectionRadians The direction in radians.
function POINT_VEC3:GetDirectionRadians( DirectionVec3 )
  local DirectionRadians = math.atan2( DirectionVec3.z, DirectionVec3.x )
  --DirectionRadians = DirectionRadians + self:GetNorthCorrectionRadians()
  if DirectionRadians < 0 then
    DirectionRadians = DirectionRadians + 2 * math.pi  -- put dir in range of 0 to 2*pi ( the full circle )
  end
  return DirectionRadians
end

--- Return the 2D distance in meters between the target POINT_VEC3 and the POINT_VEC3.
-- @param #POINT_VEC3 self
-- @param #POINT_VEC3 TargetPointVec3 The target POINT_VEC3.
-- @return Dcs.DCSTypes#Distance Distance The distance in meters.
function POINT_VEC3:Get2DDistance( TargetPointVec3 )
  local TargetVec3 = TargetPointVec3:GetVec3()
  local SourceVec3 = self:GetVec3()
  return ( ( TargetVec3.x - SourceVec3.x ) ^ 2 + ( TargetVec3.z - SourceVec3.z ) ^ 2 ) ^ 0.5
end

--- Return the 3D distance in meters between the target POINT_VEC3 and the POINT_VEC3.
-- @param #POINT_VEC3 self
-- @param #POINT_VEC3 TargetPointVec3 The target POINT_VEC3.
-- @return Dcs.DCSTypes#Distance Distance The distance in meters.
function POINT_VEC3:Get3DDistance( TargetPointVec3 )
  local TargetVec3 = TargetPointVec3:GetVec3()
  local SourceVec3 = self:GetVec3()
  return ( ( TargetVec3.x - SourceVec3.x ) ^ 2 + ( TargetVec3.y - SourceVec3.y ) ^ 2 + ( TargetVec3.z - SourceVec3.z ) ^ 2 ) ^ 0.5
end

--- Provides a Bearing / Range string
-- @param #POINT_VEC3 self
-- @param #number AngleRadians The angle in randians
-- @param #number Distance The distance
-- @return #string The BR Text
function POINT_VEC3:ToStringBR( AngleRadians, Distance )

  AngleRadians = UTILS.Round( UTILS.ToDegree( AngleRadians ), 0 )
  if self:IsMetric() then
    Distance = UTILS.Round( Distance / 1000, 2 )
  else
    Distance = UTILS.Round( UTILS.MetersToNM( Distance ), 2 )
  end

  local s = string.format( '%03d', AngleRadians ) .. ' for ' .. Distance

  s = s .. self:GetAltitudeText() -- When the POINT is a VEC2, there will be no altitude shown.

  return s
end

--- Provides a Bearing / Range string
-- @param #POINT_VEC3 self
-- @param #number AngleRadians The angle in randians
-- @param #number Distance The distance
-- @return #string The BR Text
function POINT_VEC3:ToStringLL( acc, DMS )

  acc = acc or 3
  local lat, lon = coord.LOtoLL( self:GetVec3() )
  return UTILS.tostringLL(lat, lon, acc, DMS)
end

--- Return the altitude text of the POINT_VEC3.
-- @param #POINT_VEC3 self
-- @return #string Altitude text.
function POINT_VEC3:GetAltitudeText()
  if self:IsMetric() then
    return ' at ' .. UTILS.Round( self:GetY(), 0 )
  else
    return ' at ' .. UTILS.Round( UTILS.MetersToFeet( self:GetY() ), 0 )
  end
end

--- Return a BR string from a POINT_VEC3 to the POINT_VEC3.
-- @param #POINT_VEC3 self
-- @param #POINT_VEC3 TargetPointVec3 The target POINT_VEC3.
-- @return #string The BR text.
function POINT_VEC3:GetBRText( TargetPointVec3 )
    local DirectionVec3 = self:GetDirectionVec3( TargetPointVec3 )
    local AngleRadians =  self:GetDirectionRadians( DirectionVec3 )
    local Distance = self:Get2DDistance( TargetPointVec3 )
    return self:ToStringBR( AngleRadians, Distance )
end

--- Sets the POINT_VEC3 metric or NM.
-- @param #POINT_VEC3 self
-- @param #boolean Metric true means metric, false means NM.
function POINT_VEC3:SetMetric( Metric )
  self.Metric = Metric
end

--- Gets if the POINT_VEC3 is metric or NM.
-- @param #POINT_VEC3 self
-- @return #boolean Metric true means metric, false means NM.
function POINT_VEC3:IsMetric()
  return self.Metric
end

--- Add a Distance in meters from the POINT_VEC3 horizontal plane, with the given angle, and calculate the new POINT_VEC3.
-- @param #POINT_VEC3 self
-- @param Dcs.DCSTypes#Distance Distance The Distance to be added in meters.
-- @param Dcs.DCSTypes#Angle Angle The Angle in degrees.
-- @return #POINT_VEC3 The new calculated POINT_VEC3.
function POINT_VEC3:Translate( Distance, Angle )
  local SX = self:GetX()
  local SZ = self:GetZ()
  local Radians = Angle / 180 * math.pi
  local TX = Distance * math.cos( Radians ) + SX
  local TZ = Distance * math.sin( Radians ) + SZ
  
  return POINT_VEC3:New( TX, self:GetY(), TZ )
end



--- Build an air type route point.
-- @param #POINT_VEC3 self
-- @param #POINT_VEC3.RoutePointAltType AltType The altitude type.
-- @param #POINT_VEC3.RoutePointType Type The route point type.
-- @param #POINT_VEC3.RoutePointAction Action The route point action.
-- @param Dcs.DCSTypes#Speed Speed Airspeed in km/h.
-- @param #boolean SpeedLocked true means the speed is locked.
-- @return #table The route point.
function POINT_VEC3:RoutePointAir( AltType, Type, Action, Speed, SpeedLocked )
  self:F2( { AltType, Type, Action, Speed, SpeedLocked } )

  local RoutePoint = {}
  RoutePoint.x = self:GetX()
  RoutePoint.y = self:GetZ()
  RoutePoint.alt = self:GetY()
  RoutePoint.alt_type = AltType
  
  RoutePoint.type = Type
  RoutePoint.action = Action

  RoutePoint.speed = Speed / 3.6
  RoutePoint.speed_locked = true
  
--  ["task"] = 
--  {
--      ["id"] = "ComboTask",
--      ["params"] = 
--      {
--          ["tasks"] = 
--          {
--          }, -- end of ["tasks"]
--      }, -- end of ["params"]
--  }, -- end of ["task"]


  RoutePoint.task = {}
  RoutePoint.task.id = "ComboTask"
  RoutePoint.task.params = {}
  RoutePoint.task.params.tasks = {}
  
  
  return RoutePoint
end

--- Build an ground type route point.
-- @param #POINT_VEC3 self
-- @param Dcs.DCSTypes#Speed Speed Speed in km/h.
-- @param #POINT_VEC3.RoutePointAction Formation The route point Formation.
-- @return #table The route point.
function POINT_VEC3:RoutePointGround( Speed, Formation )
  self:F2( { Formation, Speed } )

  local RoutePoint = {}
  RoutePoint.x = self:GetX()
  RoutePoint.y = self:GetZ()
  
  RoutePoint.action = Formation or ""
    

  RoutePoint.speed = Speed / 3.6
  RoutePoint.speed_locked = true
  
--  ["task"] = 
--  {
--      ["id"] = "ComboTask",
--      ["params"] = 
--      {
--          ["tasks"] = 
--          {
--          }, -- end of ["tasks"]
--      }, -- end of ["params"]
--  }, -- end of ["task"]


  RoutePoint.task = {}
  RoutePoint.task.id = "ComboTask"
  RoutePoint.task.params = {}
  RoutePoint.task.params.tasks = {}
  
  
  return RoutePoint
end


--- Smokes the point in a color.
-- @param #POINT_VEC3 self
-- @param Utilities.Utils#SMOKECOLOR SmokeColor
function POINT_VEC3:Smoke( SmokeColor )
  self:F2( { SmokeColor } )
  trigger.action.smoke( self:GetVec3(), SmokeColor )
end

--- Smoke the POINT_VEC3 Green.
-- @param #POINT_VEC3 self
function POINT_VEC3:SmokeGreen()
  self:F2()
  self:Smoke( SMOKECOLOR.Green )
end

--- Smoke the POINT_VEC3 Red.
-- @param #POINT_VEC3 self
function POINT_VEC3:SmokeRed()
  self:F2()
  self:Smoke( SMOKECOLOR.Red )
end

--- Smoke the POINT_VEC3 White.
-- @param #POINT_VEC3 self
function POINT_VEC3:SmokeWhite()
  self:F2()
  self:Smoke( SMOKECOLOR.White )
end

--- Smoke the POINT_VEC3 Orange.
-- @param #POINT_VEC3 self
function POINT_VEC3:SmokeOrange()
  self:F2()
  self:Smoke( SMOKECOLOR.Orange )
end

--- Smoke the POINT_VEC3 Blue.
-- @param #POINT_VEC3 self
function POINT_VEC3:SmokeBlue()
  self:F2()
  self:Smoke( SMOKECOLOR.Blue )
end

--- Flares the point in a color.
-- @param #POINT_VEC3 self
-- @param Utilities.Utils#FLARECOLOR FlareColor
-- @param Dcs.DCSTypes#Azimuth (optional) Azimuth The azimuth of the flare direction. The default azimuth is 0.
function POINT_VEC3:Flare( FlareColor, Azimuth )
  self:F2( { FlareColor } )
  trigger.action.signalFlare( self:GetVec3(), FlareColor, Azimuth and Azimuth or 0 )
end

--- Flare the POINT_VEC3 White.
-- @param #POINT_VEC3 self
-- @param Dcs.DCSTypes#Azimuth (optional) Azimuth The azimuth of the flare direction. The default azimuth is 0.
function POINT_VEC3:FlareWhite( Azimuth )
  self:F2( Azimuth )
  self:Flare( FLARECOLOR.White, Azimuth )
end

--- Flare the POINT_VEC3 Yellow.
-- @param #POINT_VEC3 self
-- @param Dcs.DCSTypes#Azimuth (optional) Azimuth The azimuth of the flare direction. The default azimuth is 0.
function POINT_VEC3:FlareYellow( Azimuth )
  self:F2( Azimuth )
  self:Flare( FLARECOLOR.Yellow, Azimuth )
end

--- Flare the POINT_VEC3 Green.
-- @param #POINT_VEC3 self
-- @param Dcs.DCSTypes#Azimuth (optional) Azimuth The azimuth of the flare direction. The default azimuth is 0.
function POINT_VEC3:FlareGreen( Azimuth )
  self:F2( Azimuth )
  self:Flare( FLARECOLOR.Green, Azimuth )
end

--- Flare the POINT_VEC3 Red.
-- @param #POINT_VEC3 self
function POINT_VEC3:FlareRed( Azimuth )
  self:F2( Azimuth )
  self:Flare( FLARECOLOR.Red, Azimuth )
end

end

do -- POINT_VEC2



--- POINT_VEC2 constructor.
-- @param #POINT_VEC2 self
-- @param Dcs.DCSTypes#Distance x The x coordinate of the Vec3 point, pointing to the North.
-- @param Dcs.DCSTypes#Distance y The y coordinate of the Vec3 point, pointing to the Right.
-- @param Dcs.DCSTypes#Distance LandHeightAdd (optional) The default height if required to be evaluated will be the land height of the x, y coordinate. You can specify an extra height to be added to the land height.
-- @return Core.Point#POINT_VEC2
function POINT_VEC2:New( x, y, LandHeightAdd )

  local LandHeight = land.getHeight( { ["x"] = x, ["y"] = y } )
  
  LandHeightAdd = LandHeightAdd or 0
  LandHeight = LandHeight + LandHeightAdd
  
  self = BASE:Inherit( self, POINT_VEC3:New( x, LandHeight, y ) )
  self:F2( self )
  
  return self
end

--- Create a new POINT_VEC2 object from  Vec2 coordinates.
-- @param #POINT_VEC2 self
-- @param Dcs.DCSTypes#Vec2 Vec2 The Vec2 point.
-- @return Core.Point#POINT_VEC2 self
function POINT_VEC2:NewFromVec2( Vec2, LandHeightAdd )

  local LandHeight = land.getHeight( Vec2 )

  LandHeightAdd = LandHeightAdd or 0
  LandHeight = LandHeight + LandHeightAdd
  
  self = BASE:Inherit( self, POINT_VEC3:New( Vec2.x, LandHeight, Vec2.y ) )
  self:F2( self )

  return self
end

--- Create a new POINT_VEC2 object from  Vec3 coordinates.
-- @param #POINT_VEC2 self
-- @param Dcs.DCSTypes#Vec3 Vec3 The Vec3 point.
-- @return Core.Point#POINT_VEC2 self
function POINT_VEC2:NewFromVec3( Vec3 )

  local self = BASE:Inherit( self, BASE:New() )
  local Vec2 = { x = Vec3.x, y = Vec3.z }

  local LandHeight = land.getHeight( Vec2 )
  
  self = BASE:Inherit( self, POINT_VEC3:New( Vec2.x, LandHeight, Vec2.y ) )
  self:F2( self )

  return self
end

--- Return the x coordinate of the POINT_VEC2.
-- @param #POINT_VEC2 self
-- @return #number The x coodinate.
function POINT_VEC2:GetX()
  return self.x
end

--- Return the y coordinate of the POINT_VEC2.
-- @param #POINT_VEC2 self
-- @return #number The y coodinate.
function POINT_VEC2:GetY()
  return self.z
end

--- Return the altitude of the land at the POINT_VEC2.
-- @param #POINT_VEC2 self
-- @return #number The land altitude.
function POINT_VEC2:GetAlt()
  return land.getHeight( { x = self.x, y = self.z } )
end

--- Set the x coordinate of the POINT_VEC2.
-- @param #number x The x coordinate.
function POINT_VEC2:SetX( x )
  self.x = x
end

--- Set the y coordinate of the POINT_VEC2.
-- @param #number y The y coordinate.
function POINT_VEC2:SetY( y )
  self.z = y
end



--- Calculate the distance from a reference @{#POINT_VEC2}.
-- @param #POINT_VEC2 self
-- @param #POINT_VEC2 PointVec2Reference The reference @{#POINT_VEC2}.
-- @return Dcs.DCSTypes#Distance The distance from the reference @{#POINT_VEC2} in meters.
function POINT_VEC2:DistanceFromPointVec2( PointVec2Reference )
  self:F2( PointVec2Reference )
  
  local Distance = ( ( PointVec2Reference:GetX() - self:GetX() ) ^ 2 + ( PointVec2Reference:GetY() - self:GetY() ) ^2 ) ^0.5
  
  self:T2( Distance )
  return Distance
end

--- Calculate the distance from a reference @{Dcs.DCSTypes#Vec2}.
-- @param #POINT_VEC2 self
-- @param Dcs.DCSTypes#Vec2 Vec2Reference The reference @{Dcs.DCSTypes#Vec2}.
-- @return Dcs.DCSTypes#Distance The distance from the reference @{Dcs.DCSTypes#Vec2} in meters.
function POINT_VEC2:DistanceFromVec2( Vec2Reference )
  self:F2( Vec2Reference )
  
  local Distance = ( ( Vec2Reference.x - self:GetX() ) ^ 2 + ( Vec2Reference.y - self:GetY() ) ^2 ) ^0.5
  
  self:T2( Distance )
  return Distance
end


--- Return no text for the altitude of the POINT_VEC2.
-- @param #POINT_VEC2 self
-- @return #string Empty string.
function POINT_VEC2:GetAltitudeText()
  return ''
end

--- Add a Distance in meters from the POINT_VEC2 orthonormal plane, with the given angle, and calculate the new POINT_VEC2.
-- @param #POINT_VEC2 self
-- @param Dcs.DCSTypes#Distance Distance The Distance to be added in meters.
-- @param Dcs.DCSTypes#Angle Angle The Angle in degrees.
-- @return #POINT_VEC2 The new calculated POINT_VEC2.
function POINT_VEC2:Translate( Distance, Angle )
  local SX = self:GetX()
  local SY = self:GetY()
  local Radians = Angle / 180 * math.pi
  local TX = Distance * math.cos( Radians ) + SX
  local TY = Distance * math.sin( Radians ) + SY
  
  return POINT_VEC2:New( TX, TY )
end

end