init.lua

   1 -- Hangglider mod for Minetest
   2 -- Original code by Piezo_ (orderofthefourthwall@gmail.com)
   3 -- 2018-11-14
   4
   5 -- Modifications by David G (kestral246@gmail.com)
   6 -- 2018-11-24
   7 -- For Minetest 5.x, glider's set_attach needs to be offset by 1 node
   8 --     Switch to alternate commented line below with correct offset.
   9 -- Additional tuning of parameters.
  10 -- Commented out debug hud display code, prefixed with "--debug:".
  11
  12 -- 2018-11-22
  13 -- Give visual indication that hangglider is equiped.
  14 --     Display simple overlay with blurred struts when equiped.
  15 --     Issue: don't know how to disable overlay in third person view.
  16 -- Also Unequip hangglider when landing on water.
  17 -- Attempt to linearize parabolic flight path.
  18 --     Start gravity stronger, but gradually reduce it as descent velocity increases.
  19 --     Don't use airstopper when equipped from the ground (descent velocity is low).
  20 --     Slightly increase flight speed to 1.25.
  21 -- Unequip/equip cycling mid-flight should not fly farther than continuous flight.
  22 --     When equipping mid-air (descent velocity higher), use airstopper but increase descent slope afterwards.
  23 --     Create airbreak flag so all equips mid-flight use faster descent.
  24 --     Reset airbreak flag only when land (canExist goes false).
  25 --     Issue: it wouldn't reset if land in water, use fly, and launch from air, before I added test for water,
  26 --            not sure if there are other such cases.
  27 -- Temporarily add hud debug display to show descent velocity, gravity override, and airbreak flag.
  28 --     Still in process of tuning all the parameters.
  29
  30
  31 -- Modifications by Piezo_
  32 -- 2018-11-25
  33 -- hud overlay and debug can be enabled/disabled
  34 -- Added blender-rendered overlay for struts using the actual model.
  35 -- Reduced airbreak penalty severity
  36 -- gave glider limited durability.
  37 -- Improved gravity adjustment function.
  38 -- Changed airbreaking process
  39 -- Removed airbreak penalty, as any 'advantage' seems minimal after new adjustments
  40
  41
  42 -- Modifications by gpcf
  43 -- 2018-12-09
  44 -- get shot down while flying over protected areas marked as no-fly-zones (flak, from German Flugabwehrkanone)
  45 --  set these areas with the /area_flak command
  46
  47
  48
  49 local HUD_Overlay = true --show glider struts as overlay on HUD
  50 local debug = false --show debug info in top-center of hud
  51 local moveModelUp = false
  52 if tonumber(string.sub(minetest.get_version().string, 1, 1)) and tonumber(string.sub(minetest.get_version().string, 1, 1)) > 4 then
  53         moveModelUp = true
  54 end
  55 hangglider = {} --Make this global, so other mods can tell if hangglider exists.
  56 hangglider.use = {}
  57 if HUD_Overlay then
  58 hangglider.id = {}  -- hud id for displaying overlay with struts
  59 end
  60 if debug then  hangglider.debug = {} end -- hud id for debug data
  61 --hangglider.airbreak = {}  -- true if falling fast when equip
  62
  63 minetest.register_entity("hangglider:airstopper", { --A one-instant entity that catches the player and stops them.
  64         is_visible = false,
  65         physical = false,
  66         immortal = true,
  67         attach = nil,
  68         on_step = function(self, _)
  69                 local canExist = false
  70                 if self.attach then
  71                         local player = self.attach
  72                         if player:is_player() then
  73                                 local pname = player:get_player_name()
  74                                 canExist = true
  75                                 if player:get_player_velocity().y < 0.5 and player:get_player_velocity().y > -0.5 then
  76                                         --Let go when the player actually stops, as that's the whole point.
  77                                         if hangglider.use[pname] then
  78                                                 if moveModelUp then
  79                                                         minetest.add_entity(player:get_pos(), "hangglider:glider"):set_attach(player, "", {x=0,y=10,z=0}, {x=0,y=0,z=0})
  80                                                 else
  81                                                         minetest.add_entity(player:get_pos(), "hangglider:glider"):set_attach(player, "", {x=0,y=0,z=0}, {x=0,y=0,z=0})
  82                                                 end
  83                                         end
  84                                         canExist = false
  85                                 end
  86                         end
  87                         if not canExist then
  88                                 player:set_detach()
  89                         end
  90                 end
  91                 if not canExist then
  92                         self.object:remove()
  93                 end
  94         end
  95 })
  96
  97 if areas then
  98         hangglider.flak = true
  99         -- chat command definition essentially copied from areas mod.
 100         minetest.register_chatcommand("area_flak",{
 101                 params = "<ID>",
 102                 description = "Toggle airspace restrictions for area <ID>",
 103                 func = function(name, param)
 104                         local id = tonumber(param)
 105                         if not id then
 106                                 return false, "Invalid usage, see /help area_flak."
 107                         end
 108
 109                         if not areas:isAreaOwner(id, name) then
 110                                 return false, "Area "..id.." does not exist"
 111                                         .." or is not owned by you."
 112                         end
 113                         local open = not areas.areas[id].flak
 114                         -- Save false as nil to avoid inflating the DB.
 115                         areas.areas[id].flak = open or nil
 116                         areas:save()
 117                         return true, ("Area's airspace %s."):format(open and "closed" or "opened")
 118                 end
 119         })
 120 end
 121
 122 if minetestd and minetestd.services.gravityctl.enabled then
 123 minetestd.gravityctl.register_gravity_effect("hangglider",
 124         function(player)
 125                 return hangglider.use[player:get_player_name()]
 126         end,
 127         function(gravity, player)
 128                 local vel = player:get_player_velocity()
 129                 if debug then player:hud_change(hangglider.debug[pname].id, "text", vel.y..', '..player:get_physics_override().gravity..', '..tostring(hangglider.airbreak[pname])) end
 130                 return ((vel.y + 3)/20)
 131         end,
 132         7,
 133         1000
 134 )
 135 end
 136
 137 hangglider.can_fly = function (pname, pos)
 138         -- Checks if the player will get shot down at the position
 139         if minetest.is_protected(vector.round(pos), pname) then
 140                 if hangglider.flak then
 141                         for id, area in pairs(areas:getAreasAtPos(pos)) do
 142                                 if area.flak then
 143                                         return false
 144                                 end
 145                         end
 146                 end
 147         end
 148         return true
 149 end
 150
 151 hangglider.shot_sound = function (pos)
 152         minetest.sound_play("hangglider_flak_shot", {
 153                                                         pos = pos,
 154                                                         max_hear_distance = 30,
 155                                                         gain = 10.0,
 156         })
 157 end
 158
 159 local step_v
 160 minetest.register_entity("hangglider:glider", {
 161         visual = "mesh",
 162         visual_size = {x = 12, y = 12},
 163         mesh = "glider.obj",
 164         immortal = true,
 165         static_save = false,
 166         textures = {"wool_white.png","default_wood.png"},
 167         on_step = function(self, dtime)
 168                 local canExist = false
 169                 if self.object:get_attach() then
 170                         local player = self.object:get_attach("parent")
 171                         if player then
 172                                 local pos = player:getpos()
 173                                 local pname = player:get_player_name()
 174                                 if hangglider.use[pname] then
 175                                         local mrn_name = minetest.registered_nodes[minetest.get_node(vector.new(pos.x, pos.y-0.5, pos.z)).name]
 176                                         if mrn_name then
 177                                                 if not (mrn_name.walkable or (mrn_name.drowning and mrn_name.drowning == 1)) then
 178                                                         canExist = true
 179                                                         step_v = player:get_player_velocity().y
 180                                                         if step_v < 0 then
 181                                                                 player:set_physics_override({speed=math.abs(step_v/2) + 0.75})
 182                                                         else
 183                                                                 player:set_physics_override({speed=1})
 184                                                         end
 185                                                         if not minetestd then
 186                                                                 if debug then player:hud_change(hangglider.debug[pname].id, "text", step_v..', '..player:get_physics_override().gravity..', '..tostring(hangglider.airbreak[pname])) end
 187                                                                 player:set_physics_override({gravity=((step_v + 3)/20)})
 188                                                         end
 189                                                         --[[local vel = player:get_player_velocity()
 190                                                         if debug then player:hud_change(hangglider.debug[pname].id, "text", vel.y..', '..grav..', '..tostring(hangglider.airbreak[pname])) end
 191
 192                                                         player:set_physics_override({gravity = (vel.y + 2.0)/20})
 193                                                 ]]end
 194                                         end
 195                                 end
 196                                 if not hangglider.can_fly(pname,pos) then
 197                                     if not self.warned then -- warning shot
 198                                                 self.warned = 0
 199                                                 hangglider.shot_sound(pos)
 200                                                 minetest.chat_send_player(pname, "Protected area! You will be shot down in two seconds by anti-aircraft guns!")
 201                                     end
 202                                     self.warned = self.warned + dtime
 203                                     if self.warned > 2 then -- shoot down
 204                                                 player:set_hp(1)
 205                                                 player:get_inventory():remove_item("main", ItemStack("hangglider:hangglider"))
 206                                                 hangglider.shot_sound(pos)
 207                                                 canExist = false
 208                                     end
 209                                 end
 210                                 if not canExist then
 211                                         player:set_physics_override({
 212                                                 jump = 1,
 213                                                 speed = 1,
 214                                         })
 215                                         if not minetestd then
 216                                                 player:set_physics_override({gravity=1})
 217                                         end
 218                                         hangglider.use[pname] = false
 219                                         if HUD_Overlay then
 220                                         player:hud_change(hangglider.id[pname], "text", "blank.png")
 221                                         end
 222                                         --hangglider.airbreak[pname] = false
 223                                 end
 224                         end
 225                 end
 226                 if not canExist then
 227                         self.object:set_detach()
 228                         self.object:remove()
 229                 end
 230         end
 231 })
 232
 233 minetest.register_on_dieplayer(function(player)
 234         player:set_physics_override({
 235                 gravity = 1,
 236                 jump = 1,
 237         })
 238         hangglider.use[player:get_player_name()] = false
 239 end)
 240
 241
 242 minetest.register_on_joinplayer(function(player)
 243         local pname = player:get_player_name()
 244         player:set_physics_override({
 245                 gravity = 1,
 246                 jump = 1,
 247         })
 248         hangglider.use[pname] = false
 249         if HUD_Overlay then
 250         hangglider.id[pname] = player:hud_add({
 251                 hud_elem_type = "image",
 252                 text = "blank.png",
 253                 position = {x=0, y=0},
 254                 scale = {x=-100, y=-100},
 255                 alignment = {x=1, y=1},
 256                 offset = {x=0, y=0}
 257         }) end
 258         if debug then
 259                 hangglider.debug[pname] = {id = player:hud_add({hud_elem_type = "text",
 260                         position = {x=0.5, y=0.1},
 261                         text = "-",
 262                         number = 0xFF0000}),  -- red text
 263                         -- ht = {50,50,50},
 264                 }
 265         end
 266         --hangglider.airbreak[pname] = false
 267 end)
 268
 269 minetest.register_on_leaveplayer(function(player)
 270         local pname = player:get_player_name()
 271         hangglider.use[pname] = nil
 272         if HUD_Overlay then hangglider.id[pname] = nil end
 273         if debug then hangglider.debug[pname] = nil end
 274         --hangglider.airbreak[pname] = nil
 275 end)
 276
 277 minetest.register_tool("hangglider:hangglider", {
 278         description = "Glider",
 279         inventory_image = "glider_item.png",
 280         stack_max=1,
 281         on_use = function(itemstack, player, pointed_thing)
 282                 if not player then
 283                         return
 284                 end
 285                 local pos = player:get_pos()
 286                 local pname = player:get_player_name()
 287                 if minetest.get_node(pos).name == "air" and not hangglider.use[pname] then --Equip
 288                         minetest.sound_play("bedsheet", {pos=pos, max_hear_distance = 8, gain = 1.0})
 289                         if HUD_Overlay then player:hud_change(hangglider.id[pname], "text", "glider_struts.png") end
 290                         local airbreak = false
 291                         local vel = player:get_player_velocity().y
 292                         if vel < -1.5 then  -- engage mid-air, falling fast, so stop but ramp velocity more quickly
 293                                 --hangglider.airbreak[pname] = true
 294                                 airbreak = true
 295                                 local stopper = minetest.add_entity(pos, "hangglider:airstopper")
 296                                 minetest.after(0, function(stopper, player) --"Extreme Measures"
 297                                         stopper:set_pos(player:get_pos())
 298                                         stopper:get_luaentity().attach = player
 299                                         player:set_attach( stopper, "", {x=0,y=0,z=0}, {x=0,y=0,z=0})
 300                                 end, stopper, player)
 301                         end
 302                         if not airbreak then
 303                                 if moveModelUp then
 304                                         minetest.add_entity(pos, "hangglider:glider"):set_attach(player, "", {x=0,y=10,z=0}, {x=0,y=0,z=0})
 305                                 else
 306                                         minetest.add_entity(pos, "hangglider:glider"):set_attach(player, "", {x=0,y=0,z=0}, {x=0,y=0,z=0})
 307                                 end
 308                         end
 309                         hangglider.use[pname] = true
 310                         player:set_physics_override({jump = 0})
 311                         -- if minetest 0.4.x use this:
 312
 313                         -- if minetest 5.x use this:
 314                         -- minetest.add_entity(player:get_pos(), "hangglider:glider"):set_attach(player, "", {x=0,y=10,z=0}, {x=0,y=0,z=0})
 315                         itemstack:set_wear(itemstack:get_wear() + 255)
 316                         return itemstack
 317                 elseif hangglider.use[pname] then --Unequip
 318                         if HUD_Overlay then player:hud_change(hangglider.id[pname], "text", "default_wood.png^[colorize:#0000:255") end
 319                         hangglider.use[pname] = false
 320                 end
 321         end,
 322         sound = {breaks = "default_tool_breaks"},
 323 })
 324
 325 minetest.register_craft({
 326         type = "shapeless",
 327         output = "hangglider:hangglider",
 328         recipe = {"default:paper", "default:paper", "default:paper", "default:paper", "hangglider:hangglider", "default:paper", "default:paper", "default:paper", "default:paper"},
 329 })
 330
 331 minetest.register_craft({
 332         output = "hangglider:hangglider",
 333         recipe = {
 334                 {"wool:white", "wool:white", "wool:white"},
 335                 {"default:stick", "", "default:stick"},
 336                 {"", "default:stick", ""},
 337         }
 338 })