Vanguard TV4

-- ==============================================================

--               ORBITER MODULE: VanTV4.lua

-- ==============================================================

--              Copyright 2025 (c) John Frye

--             Licensed under the MIT License

-- ==============================================================

-- load modules

separations = require "Modules.separations"

animations = require "Modules.animations"

-- register custom exhaust texture

local hTex = oapi.register_exhausttexture("Exhaust2")

-- pre load meshes

local mesh_booster = oapi.load_meshglobal("VanTV4/TV4stg1")

local mesh_sustainer = oapi.load_meshglobal("VanTV4/TV4stg2")

local mesh_fairing1 = oapi.load_meshglobal("VanTV4/TV4fairing1")

local mesh_fairing2 = oapi.load_meshglobal("VanTV4/TV4fairing2")

local mesh_third = oapi.load_meshglobal("VanTV4/TV4stg3")

local mesh_arm1 = oapi.load_meshglobal("VanTV4/TV4arm1")

local mesh_arm2 = oapi.load_meshglobal("VanTV4/TV4arm2")

local mesh_arm3 = oapi.load_meshglobal("VanTV4/TV4arm3")

local mesh_arm4 = oapi.load_meshglobal("VanTV4/TV4arm4")

local mesh_sat = oapi.load_meshglobal("VanTV4/TV4sat")

-- SetClassCaps implementation

function clbk_setclasscaps(cfg)

  -- physical vessel parameters

  vi:set_size(10.948)

  vi:set_emptymass(2997)

  vi:set_pmi({x=25.23,y=25.23,z=0.16})

  vi:set_crosssections({x=20.05,y=20.63,z=1.08})

  vi:set_rotdrag({x=0.1,y=0.1,z=0.01})

  vi:set_cameraoffset({x=0,y=0,z=10.948})

  -- touchdown points

  local tdn = {}

  tdn[1] = {pos={x=0,y=-2,z=-20},stiffness=1e7,damping=1e5,mu=3.0,mu_lng=3.0}

  tdn[2] = {pos={x=-2,y=2,z=-20},stiffness=1e7,damping=1e5,mu=3.0,mu_lng=3.0}

  tdn[3] = {pos={x=2,y=2,z=-20},stiffness=1e7,damping=1e5,mu=3.0,mu_lng=3.0}

  tdn[4] = {pos={x=0,y=0,z=11},stiffness=1e7,damping=1e5,mu=3.0,mu_lng=3.0}

  vi:set_touchdownpoints(tdn)

  -- fuel

  local hProp = vi:create_propellantresource(7279)

  -- main engine

  thmain = vi:create_thruster({pos={x=0,y=0,z=-10.948},dir={x=0,y=0,z=1},maxth0=125000,hprop=hProp,isp0=2480})

  local thgmain = vi:create_thrustergroup({thmain},THGROUP.MAIN)

  -- engine exhaust definitions

  vi:add_exhaust(thmain,40,1,{x=0,y=0,z=-10.948},{x=0, y=0, z=-1},hTex)

  -- smoke

  local exhaust_main = {

    flags = 0,

    srcsize = 2.0,

    srcrate = 13,

    v0 = 150.0,

    srcspread = 0.1,

    lifetime = 0.2,

    growthrate = 16,

    atmslowdown = 1.0,

    ltype = PARTICLE.DIFFUSE,

    levelmap = PARTICLE.LVL_PSQRT,

    lmin = 0,

    lmax = 1,

    atmsmap = PARTICLE.ATM_PLOG,

    amin = 1e-5,

    amax = 0.1,

    tex = nil

  }

  vi:add_exhauststream (thmain, {x=0,y=0,z=-14}, exhaust_main)

  -- RCS engines

  local th = 700

  local isp = 2500

  local thrcs0 = vi:create_thruster({pos={x=0,y=1.5,z=-10.5},dir={x=0,y=-1,z=0},maxth0=th,isp0=isp,hprop=hProp})

  local thrcs1 = vi:create_thruster({pos={x=0,y=-1.5,z=-10.5},dir={x=0,y=1,z=0},maxth0=th,isp0=isp,hprop=hProp})

  local thrcs2 = vi:create_thruster({pos={x=0,y=1.5,z=-10.5},dir={x=-1,y=0,z=0},maxth0=th,isp0=isp,hprop=hProp})

  local thrcs3 = vi:create_thruster({pos={x=0,y=-1.5,z=-10.5},dir={x=1,y=0,z=0},maxth0=th,isp0=isp,hprop=hProp})

  local thrcs4 = vi:create_thruster({pos={x=0,y=1.5,z=-10.5},dir={x=1,y=0,z=0},maxth0=th,isp0=isp,hprop=hProp})

  local thrcs5 = vi:create_thruster({pos={x=0,y=-1.5,z=-10.5},dir={x=-1,y=0,z=0},maxth0=th,isp0=isp,hprop=hProp})

  local thrcs6 = vi:create_thruster({pos={x=-1.5,y=0,z=-10.5},dir={x=1,y=0,z=0},maxth0=th,isp0=isp,hprop=hProp})

  local thrcs7 = vi:create_thruster({pos={x=1.5,y=0,z=-10.5},dir={x=-1,y=0,z=0},maxth0=th,isp0=isp,hprop=hProp})

  vi:create_thrustergroup({thrcs0},THGROUP.ATT_PITCHUP)

  vi:create_thrustergroup({thrcs1},THGROUP.ATT_PITCHDOWN)

  vi:create_thrustergroup({thrcs2,thrcs3},THGROUP.ATT_BANKLEFT)

  vi:create_thrustergroup({thrcs4,thrcs5},THGROUP.ATT_BANKRIGHT)

  vi:create_thrustergroup({thrcs6},THGROUP.ATT_YAWLEFT)

  vi:create_thrustergroup({thrcs7},THGROUP.ATT_YAWRIGHT)

  -- add meshes

  mh_Booster = vi:add_mesh(mesh_booster,{x=0,y=0,z=-4.237})

  mh_Sustainer = vi:add_mesh(mesh_sustainer,{x=0,y=0,z=5.362})

  mh_Fairing1 = vi:add_mesh(mesh_fairing1,{x=0,y=0,z=9.6})

  mh_Fairing2 = vi:add_mesh(mesh_fairing2,{x=0,y=0,z=9.6})

  -- make meshes only visible from the outside

  vi:set_mesh_visibility_mode(mh_Booster,MESHVIS.EXTERNAL)

  vi:set_mesh_visibility_mode(mh_Sustainer,MESHVIS.EXTERNAL)

  vi:set_mesh_visibility_mode(mh_Fairing1,MESHVIS.EXTERNAL)

  vi:set_mesh_visibility_mode(mh_Fairing2,MESHVIS.EXTERNAL)

  -- configuration status

  config = 0

end

-- Second stage

function sustainer()

  --clear previous fuel and thrusters

  vi:clear_propellantresources()

  vi:clear_thrusters()

  -- physical vessel parameters

  vi:set_size(4.49)

  vi:set_emptymass(890)

  vi:set_pmi({x=3.51,y=3.51,z=0.09})

  vi:set_crosssections({x=6.51,y=6.58,z=0.74})

  vi:set_rotdrag({x=0.1,y=0.1,z=0.01})

  vi:set_cameraoffset({x=0,y=0,z=4.49})

  -- fuel

  local hsProp = vi:create_propellantresource(1296)

  -- main engine

  local thsmain = vi:create_thruster({pos={x=0,y=0,z=-3.75},dir={x=0,y=0,z=1},maxth0=32600,hprop=hsProp,isp0=2610})

  local thsgmain = vi:create_thrustergroup({thsmain},THGROUP.MAIN)

  -- engine exhaust definitions

  vi:add_exhaust(thsmain,20,1,{x=0,y=0,z=-3.75},{x=0,y=0,z=-1},hTex)

  -- smoke

  local exhaust_main = {

    flags = 0,

    srcsize = 2.0,

    srcrate = 13,

    v0 = 150.0,

    srcspread = 0.1,

    lifetime = 0.2,

    growthrate = 16,

    atmslowdown = 1.0,

    ltype = PARTICLE.DIFFUSE,

    levelmap = PARTICLE.LVL_PSQRT,

    lmin = 0,

    lmax = 1,

    atmsmap = PARTICLE.ATM_PLOG,

    amin = 1e-5,

    amax = 0.1,

    tex = nil

  }

  vi:add_exhauststream (thsmain, {x=0,y=0,z=-5}, exhaust_main)

  -- RCS engines

  local sth = 200

  local sisp = 2500

  local thsrcs0 = vi:create_thruster({pos={x=0,y=1,z=-4.25},dir={x=0,y=-1,z=0},maxth0=sth,isp0=sisp,hprop=hsProp})

  local thsrcs1 = vi:create_thruster({pos={x=0,y=-1,z=-4.25},dir={x=0,y=1,z=0},maxth0=sth,isp0=sisp,hprop=hsProp})

  local thsrcs2 = vi:create_thruster({pos={x=0,y=1,z=-4.25},dir={x=-1,y=0,z=0},maxth0=sth,isp0=sisp,hprop=hsProp})

  local thsrcs3 = vi:create_thruster({pos={x=0,y=-1,z=-4.25},dir={x=1,y=0,z=0},maxth0=sth,isp0=sisp,hprop=hsProp})

  local thsrcs4 = vi:create_thruster({pos={x=0,y=1,z=-4.25},dir={x=1,y=0,z=0},maxth0=sth,isp0=sisp,hprop=hsProp})

  local thsrcs5 = vi:create_thruster({pos={x=0,y=-1,z=-4.25},dir={x=-1,y=0,z=0},maxth0=sth,isp0=sisp,hprop=hsProp})

  local thsrcs6 = vi:create_thruster({pos={x=-1,y=0,z=-4.25},dir={x=1,y=0,z=0},maxth0=sth,isp0=sisp,hprop=hsProp})

  local thsrcs7 = vi:create_thruster({pos={x=1,y=0,z=-4.25},dir={x=-1,y=0,z=0},maxth0=sth,isp0=sisp,hprop=hsProp})

  vi:create_thrustergroup({thsrcs0},THGROUP.ATT_PITCHUP)

  vi:create_thrustergroup({thsrcs1},THGROUP.ATT_PITCHDOWN)

  vi:create_thrustergroup({thsrcs2,thsrcs3},THGROUP.ATT_BANKLEFT)

  vi:create_thrustergroup({thsrcs4,thsrcs5},THGROUP.ATT_BANKRIGHT)

  vi:create_thrustergroup({thsrcs6},THGROUP.ATT_YAWLEFT)

  vi:create_thrustergroup({thsrcs7},THGROUP.ATT_YAWRIGHT)

  -- clear previous meshes

  vi:clear_meshes(true)

  -- add meshes

  mh_Sustainer = vi:add_mesh(mesh_sustainer,{x=0,y=0,z=5.25})

  mh_Fairing1 = vi:add_mesh(mesh_fairing1,{x=0,y=0,z=9.452})

  mh_Fairing2 = vi:add_mesh(mesh_fairing2,{x=0,y=0,z=9.452})

  mh_Third = vi:add_mesh(mesh_third,{x=0,y=0,z=7.46})

  mh_Sat = vi:add_mesh(mesh_sat,{x=0,y=0,z=8.297})

  mh_Arm1 = vi:add_mesh(mesh_arm1,{x=0,y=0.21,z=8.115})

  mh_Arm2 = vi:add_mesh(mesh_arm2,{x=-0.21,y=0,z=8.115})

  mh_Arm3 = vi:add_mesh(mesh_arm3,{x=0,y=-0.21,z=8.115})

  mh_Arm4 = vi:add_mesh(mesh_arm4,{x=0.21,y=0,z=8.115})

  -- make meshes only visible from the outside

  vi:set_mesh_visibility_mode(mh_Sustainer,MESHVIS.EXTERNAL)

  vi:set_mesh_visibility_mode(mh_Fairing1,MESHVIS.EXTERNAL)

  vi:set_mesh_visibility_mode(mh_Fairing2,MESHVIS.EXTERNAL)

  vi:set_mesh_visibility_mode(mh_Third,MESHVIS.EXTERNAL)

  vi:set_mesh_visibility_mode(mh_Sat,MESHVIS.EXTERNAL)

  vi:set_mesh_visibility_mode(mh_Arm1,MESHVIS.EXTERNAL)

  vi:set_mesh_visibility_mode(mh_Arm2,MESHVIS.EXTERNAL)

  vi:set_mesh_visibility_mode(mh_Arm3,MESHVIS.EXTERNAL)

  vi:set_mesh_visibility_mode(mh_Arm4,MESHVIS.EXTERNAL)

  -- center vessel

  vi:shiftCG({x=0.0,y=0.0,z=5.25})

  -- configuration status

  config = 1

end

-- Third stage

function third()

  --clear previous fuel and thrusters

  vi:clear_propellantresources()

  vi:clear_thrusters()

  -- physical vessel parameters

  vi:set_size(0.78)

  vi:set_emptymass(33)

  vi:set_pmi({x=0.14,y=0.14,z=0.02})

  vi:set_crosssections({x=0.57,y=0.57,z=0.15})

  vi:set_rotdrag({x=0.1,y=0.1,z=0.01})

  vi:set_cameraoffset({x=0,y=0,z=2.78})

  animations.Trans_Third()

  animations.Trans_Sat1()

  -- fuel

  local hsProp = vi:create_propellantresource(163)

  -- main engine

  local thsmain = vi:create_thruster({pos={x=0,y=0,z=-0.8},dir={x=0,y=0,z=1},maxth0=10400,hprop=hsProp,isp0=2380})

  local thsgmain = vi:create_thrustergroup({thsmain},THGROUP.MAIN)

  -- engine exhaust definitions

  vi:add_exhaust(thsmain,5,0.5,{x=0,y=0,z=-0.8},{x=0,y=0,z=-1},hTex)

  -- smoke

  local exhaust_main = {

    flags = 0,

    srcsize = 2.0,

    srcrate = 13,

    v0 = 150.0,

    srcspread = 0.1,

    lifetime = 0.2,

    growthrate = 16,

    atmslowdown = 1.0,

    ltype = PARTICLE.DIFFUSE,

    levelmap = PARTICLE.LVL_PSQRT,

    lmin = 0,

    lmax = 1,

    atmsmap = PARTICLE.ATM_PLOG,

    amin = 1e-5,

    amax = 0.1,

    tex = nil

  }

  vi:add_exhauststream (thsmain, {x=0,y=0,z=-5}, exhaust_main)

  -- clear previous meshes

  vi:clear_meshes(true)

  -- add meshes

  mh_Third = vi:add_mesh(mesh_third,{x=0,y=0,z=2.21})

  mh_Sat = vi:add_mesh(mesh_sat,{x=0,y=0,z=3.047})

  mh_Arm1 = vi:add_mesh(mesh_arm1,{x=0,y=0.21,z=2.865})

  mh_Arm2 = vi:add_mesh(mesh_arm2,{x=-0.21,y=0,z=2.865})

  mh_Arm3 = vi:add_mesh(mesh_arm3,{x=0,y=-0.21,z=2.865})

  mh_Arm4 = vi:add_mesh(mesh_arm4,{x=0.21,y=0,z=2.865})

  -- make meshes only visible from the outside

  vi:set_mesh_visibility_mode(mh_Third,MESHVIS.EXTERNAL)

  vi:set_mesh_visibility_mode(mh_Sat,MESHVIS.EXTERNAL)

  vi:set_mesh_visibility_mode(mh_Arm1,MESHVIS.EXTERNAL)

  vi:set_mesh_visibility_mode(mh_Arm2,MESHVIS.EXTERNAL)

  vi:set_mesh_visibility_mode(mh_Arm3,MESHVIS.EXTERNAL)

  vi:set_mesh_visibility_mode(mh_Arm4,MESHVIS.EXTERNAL)

  -- center vessel

  vi:shiftCG({x=0.0,y=0.0,z=2.21})

  -- configuration status

  config = 2

end

function sat()

  --clear previous fuel and thrusters

  vi:clear_propellantresources()

  vi:clear_thrusters()

  -- physical vessel parameters

  vi:set_size(0.31)

  vi:set_emptymass(1.46)

  vi:set_pmi({x=0.01,y=0.02,z=0.02})

  vi:set_crosssections({x=0.03,y=0.03,z=0.03})

  vi:set_rotdrag({x=0.01,y=0.01,z=0.01})

  vi:set_cameraoffset({x=0,y=0,z=0})

  animations.Trans_Sat2()

  -- clear previous meshes

  --vi:clear_meshes(true)

  -- add meshes

  --mh_Sat = vi:add_mesh(mesh_sat,{x=0,y=0,z=0.975})

  -- make meshes only visible from the outside

  --vi:set_mesh_visibility_mode(mh_Sat,MESHVIS.EXTERNAL)

  vi:del_mesh(0)

  vi:del_mesh(2)

  vi:del_mesh(3)

  vi:del_mesh(4)

  vi:del_mesh(5)

  -- center vessel

  vi:shiftCG({x=0.0,y=0.0,z=0.975})

  --vi:set_angvel({x=0,y=0,z=9.75})

  config = 3

end

-- Make sure fairings are only released once

local split = false

function fairings()

  if config == 1 and not split then

    split = true

    separations.fairing1_separation()

    separations.fairing2_separation()

  return

  end

end

-- Make sure arms are only released once

local released = false

function arms()

  if not released then

    released = true

    separations.arm1_separation()

    separations.arm2_separation()

    separations.arm3_separation()

    separations.arm4_separation()

  return

  end

end

-- Configuration with fairings

function fairing()

  fairing_config = 0

end

-- Configuration without fairings

function no_fairing()

  vi:del_mesh(mh_Fairing1)

  vi:del_mesh(mh_Fairing2)

  fairing_config = 1

end

-- Configuration with arms

function arm()

  arm_config = 0

end

-- Configuration without arms

function no_arm()

  vi:del_mesh(mh_Arm1)

  vi:del_mesh(mh_Arm2)

  vi:del_mesh(mh_Arm3)

  vi:del_mesh(mh_Arm4)

  arm_config = 1

end

-- Jettison the various stages

function jettison()

  if config == 0 then

    separations.booster_separation()

  elseif config == 1 then

    if fairing_config == 1 then

      separations.sustainer_separation()

    end

  end

  if config == 2 then

    if arm_config == 1 and spin_timer > 9 then

      separations.third_separation()

      separations.strap_separation()

      separations.girth1_separation()

      separations.girth2_separation()

    end

  end

end

-- Spin the third stage and satellite assembly

function third_spin1()

  if config == 2 then

    local third_status = vi:get_animation(anim_Third)

    local sat1_status = vi:get_animation(anim_Sat1)

    local third_proc = (third_status + da) % 1

    local sat1_proc = (sat1_status + da) % 1

    vi:set_animation (anim_Third, third_proc)

    if arm_config == 1 then

        vi:set_animation (anim_Sat1, sat1_proc)

    end

  end

end

-- Spin the third stage and satellite assembly

function third_spin()

  if spin_timer == nil then

    spin_timer = 0

  end

  local tm = oapi.get_simstep()

  spin_timer = spin_timer + tm

  if spin_timer >= 10 then

    spin_timer = 10

  end

  if sat1_spin == nil then

    sat1_spin = 0

  end

  if config == 2 then

  local third_status = vi:get_animation(anim_Third)

  local third_proc = (third_status + da) % 1

  vi:set_animation (anim_Third, third_proc)

  sat1_spin = (sat1_spin + (spin_timer*(tm/6.75))) % 1

  if arm_config == 1 and spin_timer > 2 then

    vi:set_animation (anim_Sat1, sat1_spin)

    end

    end

    end

-- Spin the jettisoned satellite

function sat_spin()

  if config == 3 then

    local sat2_status = vi:get_animation (anim_Sat2)

    local sat2_proc = (sat2_status + da2) % 1

    vi:set_animation (anim_Sat2, sat2_proc)

  end

end

timer = 0

function clbk_prestep(simt,simdt,mjd)

  if config == 2 then

    da = simdt * 1.5

    third_spin()

    timer = timer + simdt

    if timer < 2 then

      return

    end

    if arm_config ~= 1 then

      arms()

    end

  end

  da2 = simdt * 1.5

  sat_spin()

end

-- Keystrokes

function clbk_consumebufferedkey(key, down, kstate)

  if not down then

    return false

  end

  if oapi.keydown(kstate, OAPI_KEY.J) then

    if not vi:playback() then

      jettison()

    end

  end

  if oapi.keydown(kstate, OAPI_KEY.F) then

    if not vi:playback() then

      fairings()

    end

  end

end

-- Recording playback events

function clbk_playbackevent(simt, event_t, event_type, event)

  if event_type == "JET" then

    if event == "BOOSTER" then

      separations.booster_playback()

      return true

    elseif event == "THIRD" then

      separations.sustainer_playback()

      return true

    elseif event == "SAT" then

      separations.third_playback()

      return true

    end

  end

  if event_type == "SPLIT" then

    if event == "FAIRINGS" then

      fairings()

      return true

    elseif event == "ARMS" then

      arms()

      return true

    end

  end

  return false

end

-- Read from a saved scenario

function clbk_loadstateex(scn, vs2)

  local match = {}

  for line in scenario_lines(scn) do

    if scenario_line_match(line, "CONFIGURATION %d", match) then

      config = match.res[1]

    elseif scenario_line_match(line, "FAIRINGS %d", match) then

      fairing_config = match.res[1]

    elseif scenario_line_match(line, "ARMS %d", match) then

      arm_config = match.res[1]

    else

      vi:parse_scenario_line_ex(line, vs2)  -- unrecognised option - pass to Orbiter's generic parser

    end

  end

  if config == 1 then

    sustainer()

  elseif config == 2 then

    third()

  elseif config == 3 then

    sat()

  end

  if fairing_config == 0 then

    fairing()

  elseif fairing_config == 1 then

    no_fairing()

  end

  if arm_config == 0 then

    arm()

  elseif arm_config == 1 then

    if config ~= 3 then

    no_arm()

    end

  end

end

-- Write a saved scenario

function clbk_savestate(scn)

  oapi.writescenario_string(scn, "CONFIGURATION", tostring(config))

  oapi.writescenario_string(scn, "FAIRINGS", tostring(fairing_config))

  oapi.writescenario_string(scn, "ARMS", tostring(arm_config))

end