mods/carts/cart_entity.lua

   1 local cart_entity = {
   2         initial_properties = {
   3                 physical = false, -- otherwise going uphill breaks
   4                 collisionbox = {-0.5, -0.5, -0.5, 0.5, 0.5, 0.5},
   5                 visual = "mesh",
   6                 mesh = "carts_cart.b3d",
   7                 visual_size = {x=1, y=1},
   8                 textures = {"carts_cart.png"},
   9         },
  10
  11         driver = nil,
  12         punched = false, -- used to re-send velocity and position
  13         velocity = {x=0, y=0, z=0}, -- only used on punch
  14         old_dir = {x=1, y=0, z=0}, -- random value to start the cart on punch
  15         old_pos = nil,
  16         old_switch = 0,
  17         railtype = nil,
  18         attached_items = {}
  19 }
  20
  21 function cart_entity:on_rightclick(clicker)
  22         if not clicker or not clicker:is_player() then
  23                 return
  24         end
  25         local player_name = clicker:get_player_name()
  26         if self.driver and player_name == self.driver then
  27                 self.driver = nil
  28                 carts:manage_attachment(clicker, nil)
  29         elseif not self.driver then
  30                 self.driver = player_name
  31                 carts:manage_attachment(clicker, self.object)
  32
  33                 -- player_api does not update the animation
  34                 -- when the player is attached, reset to default animation
  35                 player_api.set_animation(clicker, "stand")
  36         end
  37 end
  38
  39 function cart_entity:on_activate(staticdata, dtime_s)
  40         self.object:set_armor_groups({immortal=1})
  41         if string.sub(staticdata, 1, string.len("return")) ~= "return" then
  42                 return
  43         end
  44         local data = minetest.deserialize(staticdata)
  45         if type(data) ~= "table" then
  46                 return
  47         end
  48         self.railtype = data.railtype
  49         if data.old_dir then
  50                 self.old_dir = data.old_dir
  51         end
  52 end
  53
  54 function cart_entity:get_staticdata()
  55         return minetest.serialize({
  56                 railtype = self.railtype,
  57                 old_dir = self.old_dir
  58         })
  59 end
  60
  61 -- 0.5.x and later: When the driver leaves
  62 function cart_entity:on_detach_child(child)
  63         if child and child:get_player_name() == self.driver then
  64                 self.driver = nil
  65         end
  66 end
  67
  68 function cart_entity:on_punch(puncher, time_from_last_punch, tool_capabilities, direction)
  69         local pos = self.object:get_pos()
  70         local vel = self.object:get_velocity()
  71         if not self.railtype or vector.equals(vel, {x=0, y=0, z=0}) then
  72                 local node = minetest.get_node(pos).name
  73                 self.railtype = minetest.get_item_group(node, "connect_to_raillike")
  74         end
  75         -- Punched by non-player
  76         if not puncher or not puncher:is_player() then
  77                 local cart_dir = carts:get_rail_direction(pos, self.old_dir, nil, nil, self.railtype)
  78                 if vector.equals(cart_dir, {x=0, y=0, z=0}) then
  79                         return
  80                 end
  81                 self.velocity = vector.multiply(cart_dir, 2)
  82                 self.punched = true
  83                 return
  84         end
  85         -- Player digs cart by sneak-punch
  86         if puncher:get_player_control().sneak then
  87                 if self.sound_handle then
  88                         minetest.sound_stop(self.sound_handle)
  89                 end
  90                 -- Detach driver and items
  91                 if self.driver then
  92                         if self.old_pos then
  93                                 self.object:set_pos(self.old_pos)
  94                         end
  95                         local player = minetest.get_player_by_name(self.driver)
  96                         carts:manage_attachment(player, nil)
  97                 end
  98                 for _, obj_ in ipairs(self.attached_items) do
  99                         if obj_ then
 100                                 obj_:set_detach()
 101                         end
 102                 end
 103                 -- Pick up cart
 104                 local inv = puncher:get_inventory()
 105                 if not (creative and creative.is_enabled_for
 106                                 and creative.is_enabled_for(puncher:get_player_name()))
 107                                 or not inv:contains_item("main", "carts:cart") then
 108                         local leftover = inv:add_item("main", "carts:cart")
 109                         -- If no room in inventory add a replacement cart to the world
 110                         if not leftover:is_empty() then
 111                                 minetest.add_item(self.object:get_pos(), leftover)
 112                         end
 113                 end
 114                 self.object:remove()
 115                 return
 116         end
 117         -- Player punches cart to alter velocity
 118         if puncher:get_player_name() == self.driver then
 119                 if math.abs(vel.x + vel.z) > carts.punch_speed_max then
 120                         return
 121                 end
 122         end
 123
 124         local punch_dir = carts:velocity_to_dir(puncher:get_look_dir())
 125         punch_dir.y = 0
 126         local cart_dir = carts:get_rail_direction(pos, punch_dir, nil, nil, self.railtype)
 127         if vector.equals(cart_dir, {x=0, y=0, z=0}) then
 128                 return
 129         end
 130
 131         local punch_interval = 1
 132         if tool_capabilities and tool_capabilities.full_punch_interval then
 133                 punch_interval = tool_capabilities.full_punch_interval
 134         end
 135         time_from_last_punch = math.min(time_from_last_punch or punch_interval, punch_interval)
 136         local f = 2 * (time_from_last_punch / punch_interval)
 137
 138         self.velocity = vector.multiply(cart_dir, f)
 139         self.old_dir = cart_dir
 140         self.punched = true
 141 end
 142
 143 local function rail_on_step_event(handler, obj, dtime)
 144         if handler then
 145                 handler(obj, dtime)
 146         end
 147 end
 148
 149 -- sound refresh interval = 1.0sec
 150 local function rail_sound(self, dtime)
 151         if not self.sound_ttl then
 152                 self.sound_ttl = 1.0
 153                 return
 154         elseif self.sound_ttl > 0 then
 155                 self.sound_ttl = self.sound_ttl - dtime
 156                 return
 157         end
 158         self.sound_ttl = 1.0
 159         if self.sound_handle then
 160                 local handle = self.sound_handle
 161                 self.sound_handle = nil
 162                 minetest.after(0.2, minetest.sound_stop, handle)
 163         end
 164         local vel = self.object:get_velocity()
 165         local speed = vector.length(vel)
 166         if speed > 0 then
 167                 self.sound_handle = minetest.sound_play(
 168                         "carts_cart_moving", {
 169                         object = self.object,
 170                         gain = (speed / carts.speed_max) / 2,
 171                         loop = true,
 172                 })
 173         end
 174 end
 175
 176 local function get_railparams(pos)
 177         local node = minetest.get_node(pos)
 178         return carts.railparams[node.name] or {}
 179 end
 180
 181 local v3_len = vector.length
 182 local function rail_on_step(self, dtime)
 183         local vel = self.object:get_velocity()
 184         if self.punched then
 185                 vel = vector.add(vel, self.velocity)
 186                 self.object:set_velocity(vel)
 187                 self.old_dir.y = 0
 188         elseif vector.equals(vel, {x=0, y=0, z=0}) then
 189                 return
 190         end
 191
 192         local pos = self.object:get_pos()
 193         local cart_dir = carts:velocity_to_dir(vel)
 194         local same_dir = vector.equals(cart_dir, self.old_dir)
 195         local update = {}
 196
 197         if self.old_pos and not self.punched and same_dir then
 198                 local flo_pos = vector.round(pos)
 199                 local flo_old = vector.round(self.old_pos)
 200                 if vector.equals(flo_pos, flo_old) then
 201                         -- Do not check one node multiple times
 202                         return
 203                 end
 204         end
 205
 206         local ctrl, player
 207
 208         -- Get player controls
 209         if self.driver then
 210                 player = minetest.get_player_by_name(self.driver)
 211                 if player then
 212                         ctrl = player:get_player_control()
 213                 end
 214         end
 215
 216         local stop_wiggle = false
 217         if self.old_pos and same_dir then
 218                 -- Detection for "skipping" nodes (perhaps use average dtime?)
 219                 -- It's sophisticated enough to take the acceleration in account
 220                 local acc = self.object:get_acceleration()
 221                 local distance = dtime * (v3_len(vel) + 0.5 * dtime * v3_len(acc))
 222
 223                 local new_pos, new_dir = carts:pathfinder(
 224                         pos, self.old_pos, self.old_dir, distance, ctrl,
 225                         self.old_switch, self.railtype
 226                 )
 227
 228                 if new_pos then
 229                         -- No rail found: set to the expected position
 230                         pos = new_pos
 231                         update.pos = true
 232                         cart_dir = new_dir
 233                 end
 234         elseif self.old_pos and self.old_dir.y ~= 1 and not self.punched then
 235                 -- Stop wiggle
 236                 stop_wiggle = true
 237         end
 238
 239         local railparams
 240
 241         -- dir:         New moving direction of the cart
 242         -- switch_keys: Currently pressed L/R key, used to ignore the key on the next rail node
 243         local dir, switch_keys = carts:get_rail_direction(
 244                 pos, cart_dir, ctrl, self.old_switch, self.railtype
 245         )
 246         local dir_changed = not vector.equals(dir, self.old_dir)
 247
 248         local new_acc = {x=0, y=0, z=0}
 249         if stop_wiggle or vector.equals(dir, {x=0, y=0, z=0}) then
 250                 vel = {x = 0, y = 0, z = 0}
 251                 local pos_r = vector.round(pos)
 252                 if not carts:is_rail(pos_r, self.railtype)
 253                                 and self.old_pos then
 254                         pos = self.old_pos
 255                 elseif not stop_wiggle then
 256                         pos = pos_r
 257                 else
 258                         pos.y = math.floor(pos.y + 0.5)
 259                 end
 260                 update.pos = true
 261                 update.vel = true
 262         else
 263                 -- Direction change detected
 264                 if dir_changed then
 265                         vel = vector.multiply(dir, math.abs(vel.x + vel.z))
 266                         update.vel = true
 267                         if dir.y ~= self.old_dir.y then
 268                                 pos = vector.round(pos)
 269                                 update.pos = true
 270                         end
 271                 end
 272                 -- Center on the rail
 273                 if dir.z ~= 0 and math.floor(pos.x + 0.5) ~= pos.x then
 274                         pos.x = math.floor(pos.x + 0.5)
 275                         update.pos = true
 276                 end
 277                 if dir.x ~= 0 and math.floor(pos.z + 0.5) ~= pos.z then
 278                         pos.z = math.floor(pos.z + 0.5)
 279                         update.pos = true
 280                 end
 281
 282                 -- Slow down or speed up..
 283                 local acc = dir.y * -4.0
 284
 285                 -- Get rail for corrected position
 286                 railparams = get_railparams(pos)
 287
 288                 -- no need to check for railparams == nil since we always make it exist.
 289                 local speed_mod = railparams.acceleration
 290                 if speed_mod and speed_mod ~= 0 then
 291                         -- Try to make it similar to the original carts mod
 292                         acc = acc + speed_mod
 293                 else
 294                         -- Handbrake or coast
 295                         if ctrl and ctrl.down then
 296                                 acc = acc - 3
 297                         else
 298                                 acc = acc - 0.4
 299                         end
 300                 end
 301
 302                 new_acc = vector.multiply(dir, acc)
 303         end
 304
 305         -- Limits
 306         local max_vel = carts.speed_max
 307         for _, v in pairs({"x","y","z"}) do
 308                 if math.abs(vel[v]) > max_vel then
 309                         vel[v] = carts:get_sign(vel[v]) * max_vel
 310                         new_acc[v] = 0
 311                         update.vel = true
 312                 end
 313         end
 314
 315         self.object:set_acceleration(new_acc)
 316         self.old_pos = vector.round(pos)
 317         if not vector.equals(dir, {x=0, y=0, z=0}) and not stop_wiggle then
 318                 self.old_dir = vector.new(dir)
 319         end
 320         self.old_switch = switch_keys
 321
 322         if self.punched then
 323                 -- Collect dropped items
 324                 for _, obj_ in pairs(minetest.get_objects_inside_radius(pos, 1)) do
 325                         if not obj_:is_player() and
 326                                         obj_:get_luaentity() and
 327                                         not obj_:get_luaentity().physical_state and
 328                                         obj_:get_luaentity().name == "__builtin:item" then
 329
 330                                 obj_:set_attach(self.object, "", {x=0, y=0, z=0}, {x=0, y=0, z=0})
 331                                 self.attached_items[#self.attached_items + 1] = obj_
 332                         end
 333                 end
 334                 self.punched = false
 335                 update.vel = true
 336         end
 337
 338         railparams = railparams or get_railparams(pos)
 339
 340         if not (update.vel or update.pos) then
 341                 rail_on_step_event(railparams.on_step, self, dtime)
 342                 return
 343         end
 344
 345         local yaw = 0
 346         if self.old_dir.x < 0 then
 347                 yaw = 0.5
 348         elseif self.old_dir.x > 0 then
 349                 yaw = 1.5
 350         elseif self.old_dir.z < 0 then
 351                 yaw = 1
 352         end
 353         self.object:set_yaw(yaw * math.pi)
 354
 355         local anim = {x=0, y=0}
 356         if dir.y == -1 then
 357                 anim = {x=1, y=1}
 358         elseif dir.y == 1 then
 359                 anim = {x=2, y=2}
 360         end
 361         self.object:set_animation(anim, 1, 0)
 362
 363         if update.vel then
 364                 self.object:set_velocity(vel)
 365         end
 366         if update.pos then
 367                 if dir_changed then
 368                         self.object:set_pos(pos)
 369                 else
 370                         self.object:move_to(pos)
 371                 end
 372         end
 373
 374         -- call event handler
 375         rail_on_step_event(railparams.on_step, self, dtime)
 376 end
 377
 378 function cart_entity:on_step(dtime)
 379         rail_on_step(self, dtime)
 380         rail_sound(self, dtime)
 381 end
 382
 383 minetest.register_entity("carts:cart", cart_entity)
 384
 385 minetest.register_craftitem("carts:cart", {
 386         description = "Cart (Sneak+Click to pick up)",
 387         inventory_image = minetest.inventorycube("carts_cart_top.png", "carts_cart_side.png", "carts_cart_side.png"),
 388         wield_image = "carts_cart_side.png",
 389         on_place = function(itemstack, placer, pointed_thing)
 390                 local under = pointed_thing.under
 391                 local node = minetest.get_node(under)
 392                 local udef = minetest.registered_nodes[node.name]
 393                 if udef and udef.on_rightclick and
 394                                 not (placer and placer:is_player() and
 395                                 placer:get_player_control().sneak) then
 396                         return udef.on_rightclick(under, node, placer, itemstack,
 397                                 pointed_thing) or itemstack
 398                 end
 399
 400                 if not pointed_thing.type == "node" then
 401                         return
 402                 end
 403                 if carts:is_rail(pointed_thing.under) then
 404                         minetest.add_entity(pointed_thing.under, "carts:cart")
 405                 elseif carts:is_rail(pointed_thing.above) then
 406                         minetest.add_entity(pointed_thing.above, "carts:cart")
 407                 else
 408                         return
 409                 end
 410
 411                 minetest.sound_play({name = "default_place_node_metal", gain = 0.5},
 412                         {pos = pointed_thing.above})
 413
 414                 if not (creative and creative.is_enabled_for
 415                                 and creative.is_enabled_for(placer:get_player_name())) then
 416                         itemstack:take_item()
 417                 end
 418                 return itemstack
 419         end,
 420 })
 421
 422 minetest.register_craft({
 423         output = "carts:cart",
 424         recipe = {
 425                 {"default:steel_ingot", "", "default:steel_ingot"},
 426                 {"default:steel_ingot", "default:steel_ingot", "default:steel_ingot"},
 427         },
 428 })