mods/carts/cart_entity.lua

   1 -- carts/cart_entity.lua
   2
   3 -- support for MT game translation.
   4 local S = carts.get_translator
   5
   6 local cart_entity = {
   7         initial_properties = {
   8                 physical = false, -- otherwise going uphill breaks
   9                 collisionbox = {-0.5, -0.5, -0.5, 0.5, 0.5, 0.5},
  10                 visual = "mesh",
  11                 mesh = "carts_cart.b3d",
  12                 visual_size = {x=1, y=1},
  13                 textures = {"carts_cart.png"},
  14         },
  15
  16         driver = nil,
  17         punched = false, -- used to re-send velocity and position
  18         velocity = {x=0, y=0, z=0}, -- only used on punch
  19         old_dir = {x=1, y=0, z=0}, -- random value to start the cart on punch
  20         old_pos = nil,
  21         old_switch = 0,
  22         railtype = nil,
  23         attached_items = {}
  24 }
  25
  26 function cart_entity:on_rightclick(clicker)
  27         if not clicker or not clicker:is_player() then
  28                 return
  29         end
  30         local player_name = clicker:get_player_name()
  31         if self.driver and player_name == self.driver then
  32                 self.driver = nil
  33                 carts:manage_attachment(clicker, nil)
  34         elseif not self.driver then
  35                 self.driver = player_name
  36                 carts:manage_attachment(clicker, self.object)
  37
  38                 -- player_api does not update the animation
  39                 -- when the player is attached, reset to default animation
  40                 player_api.set_animation(clicker, "stand")
  41         end
  42 end
  43
  44 function cart_entity:on_activate(staticdata, dtime_s)
  45         self.object:set_armor_groups({immortal=1})
  46         if string.sub(staticdata, 1, string.len("return")) ~= "return" then
  47                 return
  48         end
  49         local data = minetest.deserialize(staticdata)
  50         if type(data) ~= "table" then
  51                 return
  52         end
  53         self.railtype = data.railtype
  54         if data.old_dir then
  55                 self.old_dir = data.old_dir
  56         end
  57 end
  58
  59 function cart_entity:get_staticdata()
  60         return minetest.serialize({
  61                 railtype = self.railtype,
  62                 old_dir = self.old_dir
  63         })
  64 end
  65
  66 -- 0.5.x and later: When the driver leaves
  67 function cart_entity:on_detach_child(child)
  68         if child and child:get_player_name() == self.driver then
  69                 self.driver = nil
  70                 carts:manage_attachment(child, nil)
  71         end
  72 end
  73
  74 function cart_entity:on_punch(puncher, time_from_last_punch, tool_capabilities, direction)
  75         local pos = self.object:get_pos()
  76         local vel = self.object:get_velocity()
  77         if not self.railtype or vector.equals(vel, {x=0, y=0, z=0}) then
  78                 local node = minetest.get_node(pos).name
  79                 self.railtype = minetest.get_item_group(node, "connect_to_raillike")
  80         end
  81         -- Punched by non-player
  82         if not puncher or not puncher:is_player() then
  83                 local cart_dir = carts:get_rail_direction(pos, self.old_dir, nil, nil, self.railtype)
  84                 if vector.equals(cart_dir, {x=0, y=0, z=0}) then
  85                         return
  86                 end
  87                 self.velocity = vector.multiply(cart_dir, 2)
  88                 self.punched = true
  89                 return
  90         end
  91         -- Player digs cart by sneak-punch
  92         if puncher:get_player_control().sneak then
  93                 if self.sound_handle then
  94                         minetest.sound_stop(self.sound_handle)
  95                 end
  96                 -- Detach driver and items
  97                 if self.driver then
  98                         if self.old_pos then
  99                                 self.object:set_pos(self.old_pos)
 100                         end
 101                         local player = minetest.get_player_by_name(self.driver)
 102                         carts:manage_attachment(player, nil)
 103                 end
 104                 for _, obj_ in ipairs(self.attached_items) do
 105                         if obj_ then
 106                                 obj_:set_detach()
 107                         end
 108                 end
 109                 -- Pick up cart
 110                 local inv = puncher:get_inventory()
 111                 if not (creative and creative.is_enabled_for
 112                                 and creative.is_enabled_for(puncher:get_player_name()))
 113                                 or not inv:contains_item("main", "carts:cart") then
 114                         local leftover = inv:add_item("main", "carts:cart")
 115                         -- If no room in inventory add a replacement cart to the world
 116                         if not leftover:is_empty() then
 117                                 minetest.add_item(self.object:get_pos(), leftover)
 118                         end
 119                 end
 120                 self.object:remove()
 121                 return
 122         end
 123         -- Player punches cart to alter velocity
 124         if puncher:get_player_name() == self.driver then
 125                 if math.abs(vel.x + vel.z) > carts.punch_speed_max then
 126                         return
 127                 end
 128         end
 129
 130         local punch_dir = carts:velocity_to_dir(puncher:get_look_dir())
 131         punch_dir.y = 0
 132         local cart_dir = carts:get_rail_direction(pos, punch_dir, nil, nil, self.railtype)
 133         if vector.equals(cart_dir, {x=0, y=0, z=0}) then
 134                 return
 135         end
 136
 137         local punch_interval = 1
 138         if tool_capabilities and tool_capabilities.full_punch_interval then
 139                 punch_interval = tool_capabilities.full_punch_interval
 140         end
 141         time_from_last_punch = math.min(time_from_last_punch or punch_interval, punch_interval)
 142         local f = 2 * (time_from_last_punch / punch_interval)
 143
 144         self.velocity = vector.multiply(cart_dir, f)
 145         self.old_dir = cart_dir
 146         self.punched = true
 147 end
 148
 149 local function rail_on_step_event(handler, obj, dtime)
 150         if handler then
 151                 handler(obj, dtime)
 152         end
 153 end
 154
 155 -- sound refresh interval = 1.0sec
 156 local function rail_sound(self, dtime)
 157         if not self.sound_ttl then
 158                 self.sound_ttl = 1.0
 159                 return
 160         elseif self.sound_ttl > 0 then
 161                 self.sound_ttl = self.sound_ttl - dtime
 162                 return
 163         end
 164         self.sound_ttl = 1.0
 165         if self.sound_handle then
 166                 local handle = self.sound_handle
 167                 self.sound_handle = nil
 168                 minetest.after(0.2, minetest.sound_stop, handle)
 169         end
 170         local vel = self.object:get_velocity()
 171         local speed = vector.length(vel)
 172         if speed > 0 then
 173                 self.sound_handle = minetest.sound_play(
 174                         "carts_cart_moving", {
 175                         object = self.object,
 176                         gain = (speed / carts.speed_max) / 2,
 177                         loop = true,
 178                 })
 179         end
 180 end
 181
 182 local function get_railparams(pos)
 183         local node = minetest.get_node(pos)
 184         return carts.railparams[node.name] or {}
 185 end
 186
 187 local v3_len = vector.length
 188 local function rail_on_step(self, dtime)
 189         local vel = self.object:get_velocity()
 190         if self.punched then
 191                 vel = vector.add(vel, self.velocity)
 192                 self.object:set_velocity(vel)
 193                 self.old_dir.y = 0
 194         elseif vector.equals(vel, {x=0, y=0, z=0}) then
 195                 return
 196         end
 197
 198         local pos = self.object:get_pos()
 199         local cart_dir = carts:velocity_to_dir(vel)
 200         local same_dir = vector.equals(cart_dir, self.old_dir)
 201         local update = {}
 202
 203         if self.old_pos and not self.punched and same_dir then
 204                 local flo_pos = vector.round(pos)
 205                 local flo_old = vector.round(self.old_pos)
 206                 if vector.equals(flo_pos, flo_old) then
 207                         -- Do not check one node multiple times
 208                         return
 209                 end
 210         end
 211
 212         local ctrl, player
 213
 214         -- Get player controls
 215         if self.driver then
 216                 player = minetest.get_player_by_name(self.driver)
 217                 if player then
 218                         ctrl = player:get_player_control()
 219                 end
 220         end
 221
 222         local stop_wiggle = false
 223         if self.old_pos and same_dir then
 224                 -- Detection for "skipping" nodes (perhaps use average dtime?)
 225                 -- It's sophisticated enough to take the acceleration in account
 226                 local acc = self.object:get_acceleration()
 227                 local distance = dtime * (v3_len(vel) + 0.5 * dtime * v3_len(acc))
 228
 229                 local new_pos, new_dir = carts:pathfinder(
 230                         pos, self.old_pos, self.old_dir, distance, ctrl,
 231                         self.old_switch, self.railtype
 232                 )
 233
 234                 if new_pos then
 235                         -- No rail found: set to the expected position
 236                         pos = new_pos
 237                         update.pos = true
 238                         cart_dir = new_dir
 239                 end
 240         elseif self.old_pos and self.old_dir.y ~= 1 and not self.punched then
 241                 -- Stop wiggle
 242                 stop_wiggle = true
 243         end
 244
 245         local railparams
 246
 247         -- dir:         New moving direction of the cart
 248         -- switch_keys: Currently pressed L/R key, used to ignore the key on the next rail node
 249         local dir, switch_keys = carts:get_rail_direction(
 250                 pos, cart_dir, ctrl, self.old_switch, self.railtype
 251         )
 252         local dir_changed = not vector.equals(dir, self.old_dir)
 253
 254         local new_acc = {x=0, y=0, z=0}
 255         if stop_wiggle or vector.equals(dir, {x=0, y=0, z=0}) then
 256                 vel = {x = 0, y = 0, z = 0}
 257                 local pos_r = vector.round(pos)
 258                 if not carts:is_rail(pos_r, self.railtype)
 259                                 and self.old_pos then
 260                         pos = self.old_pos
 261                 elseif not stop_wiggle then
 262                         pos = pos_r
 263                 else
 264                         pos.y = math.floor(pos.y + 0.5)
 265                 end
 266                 update.pos = true
 267                 update.vel = true
 268         else
 269                 -- Direction change detected
 270                 if dir_changed then
 271                         vel = vector.multiply(dir, math.abs(vel.x + vel.z))
 272                         update.vel = true
 273                         if dir.y ~= self.old_dir.y then
 274                                 pos = vector.round(pos)
 275                                 update.pos = true
 276                         end
 277                 end
 278                 -- Center on the rail
 279                 if dir.z ~= 0 and math.floor(pos.x + 0.5) ~= pos.x then
 280                         pos.x = math.floor(pos.x + 0.5)
 281                         update.pos = true
 282                 end
 283                 if dir.x ~= 0 and math.floor(pos.z + 0.5) ~= pos.z then
 284                         pos.z = math.floor(pos.z + 0.5)
 285                         update.pos = true
 286                 end
 287
 288                 -- Slow down or speed up..
 289                 local acc = dir.y * -4.0
 290
 291                 -- Get rail for corrected position
 292                 railparams = get_railparams(pos)
 293
 294                 -- no need to check for railparams == nil since we always make it exist.
 295                 local speed_mod = railparams.acceleration
 296                 if speed_mod and speed_mod ~= 0 then
 297                         -- Try to make it similar to the original carts mod
 298                         acc = acc + speed_mod
 299                 else
 300                         -- Handbrake or coast
 301                         if ctrl and ctrl.down then
 302                                 acc = acc - 3
 303                         else
 304                                 acc = acc - 0.4
 305                         end
 306                 end
 307
 308                 new_acc = vector.multiply(dir, acc)
 309         end
 310
 311         -- Limits
 312         local max_vel = carts.speed_max
 313         for _, v in pairs({"x","y","z"}) do
 314                 if math.abs(vel[v]) > max_vel then
 315                         vel[v] = carts:get_sign(vel[v]) * max_vel
 316                         new_acc[v] = 0
 317                         update.vel = true
 318                 end
 319         end
 320
 321         self.object:set_acceleration(new_acc)
 322         self.old_pos = vector.round(pos)
 323         if not vector.equals(dir, {x=0, y=0, z=0}) and not stop_wiggle then
 324                 self.old_dir = vector.new(dir)
 325         end
 326         self.old_switch = switch_keys
 327
 328         if self.punched then
 329                 -- Collect dropped items
 330                 for _, obj_ in pairs(minetest.get_objects_inside_radius(pos, 1)) do
 331                         local ent = obj_:get_luaentity()
 332                         -- Careful here: physical_state and disable_physics are item-internal APIs
 333                         if ent and ent.name == "__builtin:item" and ent.physical_state then
 334                                 ent:disable_physics()
 335                                 obj_:set_attach(self.object, "", {x=0, y=0, z=0}, {x=0, y=0, z=0})
 336                                 self.attached_items[#self.attached_items + 1] = obj_
 337                         end
 338                 end
 339                 self.punched = false
 340                 update.vel = true
 341         end
 342
 343         railparams = railparams or get_railparams(pos)
 344
 345         if not (update.vel or update.pos) then
 346                 rail_on_step_event(railparams.on_step, self, dtime)
 347                 return
 348         end
 349
 350         local yaw = 0
 351         if self.old_dir.x < 0 then
 352                 yaw = 0.5
 353         elseif self.old_dir.x > 0 then
 354                 yaw = 1.5
 355         elseif self.old_dir.z < 0 then
 356                 yaw = 1
 357         end
 358         self.object:set_yaw(yaw * math.pi)
 359
 360         local anim = {x=0, y=0}
 361         if dir.y == -1 then
 362                 anim = {x=1, y=1}
 363         elseif dir.y == 1 then
 364                 anim = {x=2, y=2}
 365         end
 366         self.object:set_animation(anim, 1, 0)
 367
 368         if update.vel then
 369                 self.object:set_velocity(vel)
 370         end
 371         if update.pos then
 372                 if dir_changed then
 373                         self.object:set_pos(pos)
 374                 else
 375                         self.object:move_to(pos)
 376                 end
 377         end
 378
 379         -- call event handler
 380         rail_on_step_event(railparams.on_step, self, dtime)
 381 end
 382
 383 function cart_entity:on_step(dtime)
 384         rail_on_step(self, dtime)
 385         rail_sound(self, dtime)
 386 end
 387
 388 minetest.register_entity("carts:cart", cart_entity)
 389
 390 minetest.register_craftitem("carts:cart", {
 391         description = S("Cart") .. "\n" .. S("(Sneak+Click to pick up)"),
 392         inventory_image = minetest.inventorycube("carts_cart_top.png", "carts_cart_front.png", "carts_cart_side.png"),
 393         wield_image = "carts_cart_side.png",
 394         on_place = function(itemstack, placer, pointed_thing)
 395                 local under = pointed_thing.under
 396                 local node = minetest.get_node(under)
 397                 local udef = minetest.registered_nodes[node.name]
 398                 if udef and udef.on_rightclick and
 399                                 not (placer and placer:is_player() and
 400                                 placer:get_player_control().sneak) then
 401                         return udef.on_rightclick(under, node, placer, itemstack,
 402                                 pointed_thing) or itemstack
 403                 end
 404
 405                 if not pointed_thing.type == "node" then
 406                         return
 407                 end
 408                 if carts:is_rail(pointed_thing.under) then
 409                         minetest.add_entity(pointed_thing.under, "carts:cart")
 410                 elseif carts:is_rail(pointed_thing.above) then
 411                         minetest.add_entity(pointed_thing.above, "carts:cart")
 412                 else
 413                         return
 414                 end
 415
 416                 minetest.sound_play({name = "default_place_node_metal", gain = 0.5},
 417                         {pos = pointed_thing.above}, true)
 418
 419                 if not (creative and creative.is_enabled_for
 420                                 and creative.is_enabled_for(placer:get_player_name())) then
 421                         itemstack:take_item()
 422                 end
 423                 return itemstack
 424         end,
 425 })
 426
 427 minetest.register_craft({
 428         output = "carts:cart",
 429         recipe = {
 430                 {"default:steel_ingot", "", "default:steel_ingot"},
 431                 {"default:steel_ingot", "default:steel_ingot", "default:steel_ingot"},
 432         },
 433 })