SetMoveTypeDataExample

function gadget:GetInfo()
  return {
    name      = "FlashTurnRate",
    desc      = "Adds an option for flashes and friends to turn faster but go slower",
    author    = "Baczek",
    date      = "26 Dec 2009",
    license   = "GNU GPL, v2 or later",
    layer     = 0,
    enabled   = true  --  loaded by default?
  }
end

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if (not gadgetHandler:IsSyncedCode()) then
  return
end

local EditUnitCmdDesc = Spring.EditUnitCmdDesc
local FindUnitCmdDesc = Spring.FindUnitCmdDesc
local InsertUnitCmdDesc = Spring.InsertUnitCmdDesc
local GiveOrderToUnit = Spring.GiveOrderToUnit
local SetUnitNeutral = Spring.SetUnitNeutral
local GetUnitMoveTypeData = Spring.GetUnitMoveTypeData
local SetGroundMoveTypeData = Spring.MoveCtrl.SetGroundMoveTypeData
local SetGunshipMoveTypeData = Spring.MoveCtrl.SetGunshipMoveTypeData

local FLASH = {
  [UnitDefNames["armflash"].id] = true,
  [UnitDefNames["corgator"].id] = true,
  [UnitDefNames["armatlas"].id] = true,
}

local flashList = {}

local CMD_SET_TR = 34581

local turnCmd = {
      id      = CMD_SET_TR,
      name    = "flashTurnRate",
      action  = "flashTurnRate",
      type    = CMDTYPE.ICON_MODE,
      tooltip = "Changes the turn rate of the Flash",
      params  = { '0', '  Lo  ', '  Hi  '}
}


function gadget:UnitCreated(unitID, unitDefID, unitTeam, builderID)
  if FLASH[unitDefID] then
    InsertUnitCmdDesc(unitID, 500, turnCmd)
    local tr = UnitDefs[unitDefID].turnRate
    local ms = UnitDefs[unitDefID].speed
    flashList[unitID] = {orgturnrate=tr, orgspeed=ms}
  end
end

function gadget:UnitDestroyed(unitID, unitDefID, unitTeam)
  flashList[unitID] = nil
end

function gadget:AllowCommand(unitID, unitDefID, teamID, cmdID, cmdParams, cmdOptions)
  if FLASH[unitDefID] then
    if (cmdID == CMD_SET_TR) then 
      local mt = GetUnitMoveTypeData(unitID)
      Spring.Echo("turnRate="..tostring(mt.turnRate))
      if mt.name ~= "ground" and mt.name ~= "gunship" then return false end
      local cmdDescID = FindUnitCmdDesc(unitID, CMD_SET_TR)
      Spring.Echo("cmdparams[1]=" .. tostring(cmdParams[1]))
      if mt.name == "ground" then 
        SetGroundMoveTypeData(unitID, {
                turnRate=(1+cmdParams[1]) * flashList[unitID].orgturnrate,
                maxSpeed=flashList[unitID].orgspeed / (1+cmdParams[1])
        })
      elseif mt.name == "gunship" then
        -- setting maxSpeed on gunships should automatically adjust
        -- brakeDistance
        SetGunshipMoveTypeData(unitID, {
                turnRate=(1+cmdParams[1]) * flashList[unitID].orgturnrate,
                maxSpeed=flashList[unitID].orgspeed / (1+cmdParams[1])
        })
      end
      turnCmd.params[1] = cmdParams[1]
      EditUnitCmdDesc(unitID, cmdDescID, turnCmd)
      turnCmd.params[1] = 1
      return false
    end
  end
  return true
end