Pathfinding: Cleanup jumper.lua

Add copyright notices to jumper.lua
Remove 'pathfinder2.lua'
This commit is contained in:
Zorman2000 2017-04-04 10:11:19 -04:00
parent 297dd379a6
commit 7f2e1b665a
3 changed files with 74 additions and 311 deletions

View File

@ -1,20 +1,51 @@
-- Code based on Jumper library
---------------------------------------------------------------------------------------
-- This code is entirely based on the Jumper library by Roland Yonaba.
-- The modifications are only to make it work under Minetest's secure
-- environment. Therefore, the code in this file is under the MIT license
-- as the original Jumper library. The original library code can be found
-- here: https://github.com/Yonaba/Jumper
--- The Pathfinder class
-- Modifications are by Hector Franqui (Zorman2000)
-- Modification by Zorman2000:
-- This file has been modified to be usable with Minetest.
-- Do to Minetest's mod security, the global "require()" call
-- is disabled, and needs to be replaced by one using Minetest's
-- environment.
-- - Get Minetest's insecure environment
-- - Change all "require" calls to "ie.require()"
--
-- The rest of the code is left intact and is (c) 2012-2013 Roland Yonaba
---------------------------------------------------------------------------------------
-- Copyright (c) 2012-2013 Roland Yonaba
-- Permission is hereby granted, free of charge, to any person obtaining a
-- copy of this software and associated documentation files (the
-- "Software"), to deal in the Software without restriction, including
-- without limitation the rights to use, copy, modify, merge, publish,
-- distribute, sublicense, and/or sell copies of the Software, and to
-- permit persons to whom the Software is furnished to do so, subject to
-- the following conditions:
-- The above copyright notice and this permission notice shall be included
-- in all copies or substantial portions of the Software.
-- THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
-- OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
-- MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
-- IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY
-- CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT,
-- TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE
-- SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
--
---------------------------------------------------------------------------------------
---------------------------------------------------------------------------------------
---------------------------------------------------------------------------------------
-- Local variables declarations
local abs = math.abs
local sqrt = math.sqrt
local max = math.max
local floor = math.floor
local t_insert, t_remove = table.insert, table.remove
local huge = math.huge
---------------------------------------------------------------------------------------
-- Heuristics based on implementation by Ronald Yonaba
-- Original code here: https://github.com/Yonaba/Jumper/jumper/core/heuristics.lua
---------------------------------------------------------------------------------------
local Heuristics = {
['MANHATTAN'] = function(nodeA, nodeB)
local dx = abs(nodeA._x - nodeB._x)
@ -28,6 +59,11 @@ local Heuristics = {
end
}
---------------------------------------------------------------------------------------
-- Node class implementation by Ronald Yonaba
-- Original code here: https://github.com/Yonaba/Jumper/jumper/core/node.lua
---------------------------------------------------------------------------------------
local Node = setmetatable({},
{__call = function(self,...)
return Node:new(...)
@ -106,14 +142,11 @@ local Node = setmetatable({},
return self
end
---------------------------------------------------------------
-- Path class implementation by Ronald Yonaba
-- Original code here:
---------------------------------------------------------------
-- Local references
local abs, max = math.abs, math.max
local t_insert, t_remove = table.insert, table.remove
---------------------------------------------------------------------------------------
-- Path class implementation by Ronald Yonaba
-- Original code here: https://github.com/Yonaba/Jumper/jumper/core/path.lua
---------------------------------------------------------------------------------------
--- The `Path` class.<br/>
-- This class is callable.
-- Therefore, <em><code>Path(...)</code></em> acts as a shortcut to <em><code>Path:new(...)</code></em>.
@ -294,12 +327,12 @@ function Path:append(p)
for node in p:nodes() do self:addNode(node) end
return self
end
-- Local reference
local floor = math.floor
---------------------------------------------------------------------------------------
-- Utils class based on implementation by Ronald Yonaba
-- Original code here: https://github.com/Yonaba/Jumper/jumper/core/utils.lua
---------------------------------------------------------------------------------------
local Utils = {
traceBackPath = function(finder, node, startNode)
local path = Path:new()
@ -358,11 +391,11 @@ local Utils = {
end
}
---------------------------------------------------------------
-- B-Heap implementation by Ronald Yonaba
-- Original code here:
---------------------------------------------------------------
---------------------------------------------------------------------------------------
-- Bheap class implementation by Ronald Yonaba
-- Original code here: https://github.com/Yonaba/Jumper/jumper/core/bheap.lua
---------------------------------------------------------------------------------------
-- Default comparison function
local function f_min(a,b) return a < b end
@ -507,15 +540,15 @@ function heap:heapify(item)
return self
end
---------------------------------------------------------------
-- Grid implementation by Ronald Yonaba
-- Original code here:
---------------------------------------------------------------
---------------------------------------------------------------------------------------
-- Grid class implementation by Ronald Yonaba
-- Original code here: https://github.com/Yonaba/Jumper/jumper/grid.lua
---------------------------------------------------------------------------------------
local pairs = pairs
local assert = assert
local next = next
local setmetatable = setmetatable
local floor = math.floor
local coroutine = coroutine
-- Offsets for straights moves
@ -904,13 +937,12 @@ function PostProcessGrid:getNodeAt(x,y)
end
---------------------------------------------------------------
-- A* algorithm implementation by Ronald Yonaba
-- Original code here:
---------------------------------------------------------------
---------------------------------------------------------------------------------------
-- A* algorithm based on implementation by Ronald Yonaba
-- Original code here: https://github.com/Yonaba/Jumper/jumper/search/astar.lua
---------------------------------------------------------------------------------------
-- Internalization
local ipairs = ipairs
local huge = math.huge
-- Updates G-cost
local function computeCost(node, neighbour, finder, clearance)
@ -973,6 +1005,11 @@ local function ASTAR(finder, startNode, endNode, clearance, toClear, overrideHeu
return nil
end
---------------------------------------------------------------------------------------
-- Pathfinder class based on implementation by Ronald Yonaba
-- Original code here: https://github.com/Yonaba/Jumper/jumper/pathfinder.lua
---------------------------------------------------------------------------------------
local Finders = {
['ASTAR'] = ASTAR
}

View File

@ -1,274 +0,0 @@
-- Pathfinder by Zorman2000
-- Pathfinding code with included A* implementation, customized
-- for Minetest. At the moment, paths can only be found in flat
-- terrain (only 2D pathfinding)
-- Public namespace
pathfinder = {}
-- Private namespace for pathfinder functions
local finder = {}
pathfinder.node_types = {
start = 0,
goal = 1,
walkable = 2,
openable = 3,
non_walkable = 4
}
pathfinder.nodes = {
openable_prefix = {
"doors:",
"cottages:gate",
"cottages:half_door"
}
}
function pathfinder.find_path(start_pos, end_pos, extra_range, walkable_nodes)
-- Create map
local map = finder.create_map(start_pos, end_pos, extra_range, walkable_nodes)
minetest.log("Number of nodes in map: "..dump(#map))
-- Use A* algorithm
local path = minetest.find_path(start_pos, end_pos, 30, 1, 1, "Dijkstra")
minetest.log("Path: "..dump(path))
return path
--return finder.astar({name="air", pos=start_pos}, {name="air", pos=end_pos}, map)
end
-- This function is used to determine if a node is walkable
-- or openable, in which case is good to use when finding a path
function finder.is_good_node(node, exceptions)
-- Is openable is to support doors, fence gates and other
-- doors from other mods. Currently, default doors, gates
-- and cottages doors are supported.
local is_openable = false
for _,node_prefix in pairs(pathfinder.nodes.openable_prefix) do
local start_i,end_i = string.find(node.name, node_prefix)
if start_i ~= nil then
is_openable = true
break
end
end
if node ~= nil and node.name ~= nil and not minetest.registered_nodes[node.name].walkable then
return pathfinder.node_types.walkable
elseif is_openable then
return pathfinder.node_types.openable
else
for i = 1, #exceptions do
if node.name == exceptions[i] then
return pathfinder.node_types.walkable
end
end
return pathfinder.node_types.non_walkable
end
end
-- Maps a 2D slice of Minetest terrain into an array of nodes
-- Extra range is a number that will be added in the x and the z coordinates
-- to allow more room to find paths.
-- Walkables is an array of node names which are considered walkable,
-- even if they are not.
function finder.create_map(start_pos, end_pos, extra_range, walkables)
minetest.log("Start pos: "..minetest.pos_to_string(start_pos))
minetest.log("End pos: "..minetest.pos_to_string(end_pos))
-- Calculate all signs to ensure:
-- 1. Correct area calculation
-- 2. Iterate in the correct direction
local start_x_sign = (start_pos.x - end_pos.x) / math.abs(start_pos.x - end_pos.x)
local start_z_sign = (start_pos.z - end_pos.z) / math.abs(start_pos.z - end_pos.z)
local end_x_sign = (end_pos.x - start_pos.x) / math.abs(end_pos.x - start_pos.x)
local end_z_sign = (end_pos.z - start_pos.z) / math.abs(end_pos.z - start_pos.z)
-- Correct the signs if they are nan
if math.abs(start_pos.x - end_pos.x) == 0 then
start_x_sign = -1
end_x_sign = 1
end
if math.abs(start_pos.z - end_pos.z) == 0 then
start_z_sign = -1
end_z_sign = 1
end
-- Get starting and ending positions, adding the extra nodes to the area
local pos1 = {x=start_pos.x + (extra_range * start_x_sign), y = start_pos.y - 1, z=start_pos.z + (extra_range * start_z_sign)}
local pos2 = {x=end_pos.x + (extra_range * end_x_sign), y = end_pos.y, z=end_pos.z + (extra_range * end_z_sign)}
minetest.log("Recalculated pos1: "..minetest.pos_to_string(pos1))
minetest.log("Recalculated pos2: "..minetest.pos_to_string(pos2))
local grid = {}
-- Loop through the area and classify nodes
for z = 1, math.abs(pos1.z - pos2.z) do
--local current_row = {}
for x = 1, math.abs(pos1.x - pos2.x) do
-- Calculate current position
local current_pos = {x=pos1.x + (x*end_x_sign), y=pos1.y, z=pos1.z + (z*end_z_sign)}
-- Get node info
local node = minetest.get_node(current_pos)
-- Check if this is the starting position
if current_pos.x == start_pos.x and current_pos.z == start_pos.z then
-- Is start position
table.insert(grid, {name=node.name, pos=current_pos, type=pathfinder.node_types.start})
elseif current_pos.x == end_pos.x and current_pos.z == end_pos.z then
-- Is ending position or goal position
table.insert(grid, {name=node.name, pos=current_pos, type=pathfinder.node_types.goal})
else
-- Check if node is walkable
if node.name == "air" then
-- If air do no more checks
table.insert(grid, {name=node.name, pos=current_pos, type=pathfinder.node_types.walkable})
else
-- Check if it is of a walkable or openable type
table.insert(grid, {name=node.name, pos=current_pos, type=finder.is_good_node(node, walkables)})
end
end
end
-- Insert the converted row into the grid
--table.insert(grid, current_row)
end
return grid
end
--------------------------------------------------------------------------
-- A* algorithm implementation
--------------------------------------------------------------------------
-- Utility functions
function finder.distance(node1, node2)
return math.sqrt(math.pow(node2.pos.x - node1.pos.x, 2) + math.pow(node2.pos.z - node1.pos.z, 2))
end
function finder.is_valid_neighbor(node1, node2)
-- Consider only orthogonal nodes
if (node1.pos.x == node2.pos.x and node1.pos.z ~= node2.pos.z)
or (node1.pos.z == node2.pos.z and node1.pos.x ~= node2.pos.z) then
if (finder.distance(node1, node2) < 2) then
return finder.is_good_node(node2, {})
end
end
return false
end
function finder.cost_estimate(node1, node2)
return finder.distance(node1, node2)
end
function finder.get_lowest_fscore(nodes, f_scores)
local lowest = 1/0
local best_node = nil
for _, node in pairs(nodes) do
local score = f_scores[node]
if score < lowest then
lowest = score
best_node = node
end
end
return best_node
end
function finder.get_neighbor(node, nodes)
local neighbors = {}
for _, current_node in pairs(nodes) do
if current_node ~= node then
if finder.is_valid_neighbor(node, current_node) then
table.insert(neighbors, current_node)
end
end
end
return neighbors
end
function finder.contains_node(node, all_nodes)
for _,current_node in pairs(all_nodes) do
if current_node == node then
return true
end
end
return false
end
function finder.remove_node(node, all_nodes)
--minetest.log("On remove_node: "..dump(all_nodes))
for key, current_node in pairs(all_nodes) do
if current_node == node then
--minetest.log("Table before: "..dump(all_nodes))
table.remove(all_nodes, key)
--minetest.log("Table after: "..dump(all_nodes))
return
end
end
end
function finder.create_path(path, grid, node)
if grid[node] ~= nil then
table.insert(path, 1, grid[node])
return create_path(path, grid, grid[node])
else
return path
end
end
function finder.astar(start_pos, end_pos, nodes)
local closed_set = {}
local open_set = {
start_pos
}
local came_from = {}
local g_score = {}
local f_score = {}
g_score[start_pos] = 0
f_score[start_pos] = g_score[start_pos] + finder.cost_estimate(start_pos, end_pos)
minetest.log("Open set: "..dump(#open_set))
while #open_set > 0 do
minetest.log("Nodes size: "..dump(#nodes))
local current = finder.get_lowest_fscore(open_set, f_score)
minetest.log("Node with best fscore: "..dump(current))
if current == end_pos then
minetest.log("Creating path: "..dump(came_from))
local path = create_path({}, came_from, end_pos)
table.insert(path, end_pos)
return path
end
minetest.log("Removing node from openset..."..dump(#open_set))
finder.remove_node(current, open_set)
minetest.log("Removed. Open set size: "..dump(#open_set))
minetest.log("Adding to closed set..."..dump(#closed_set))
table.insert(closed_set, current)
minetest.log("Added. New closed set size: "..dump(#closed_set))
local neighbors = finder.get_neighbor(current, nodes)
minetest.log("Found "..dump(#neighbors).." neighbors for current node")--dump(neighbors))
for _, neighbor in pairs(neighbors) do
minetest.log("Currently looking at neighbor: "..minetest.pos_to_string(neighbor.pos))
if finder.contains_node(neighbor, closed_set) == false then
minetest.log("Node is not in closed set")
local tentative_g_score = g_score[current] + finder.distance(current, neighbor)
minetest.log("Tentative g score is: "..dump(tentative_g_score))
minetest.log("Logic: "..dump(finder.contains_node(neighbor, open_set) == false or tentative_g_score < g_score[neighbor]))
if finder.contains_node(neighbor, open_set) == false or tentative_g_score < g_score[neighbor] then
came_from[neighbor] = current
minetest.log("Added node to came_from set: "..dump(table.getn(came_from)))
g_score[neighbor] = tentative_g_score
f_score[neighbor] = g_score[neighbor] + finder.cost_estimate(neighbor, end_pos)
if finder.contains_node(neighbor, open_set) == false then
minetest.log("Adding neighbor node to open_set: "..dump(#open_set))
table.insert(open_set, neighbor)
minetest.log("Added. New open set size: "..dump(#open_set))
end
end
end
end
end
-- Path not found
return nil
end

View File

@ -273,7 +273,7 @@ function npc.initialize(entity, pos, is_lua_entity)
minetest.log("Self destination: "..minetest.pos_to_string(nodes[1]))
local path = pathfinder.find_path(ent.object:getpos(), nodes[1], 20, {})
--local path = pathfinder.find_path(ent.object:getpos(), nodes[1], 20, {})
--minetest.log("Path to node: "..dump(path))
--npc.add_action(ent, npc.actions.use_door, {self = ent, pos = nodes[1], action = npc.actions.door_action.OPEN})
--npc.add_action(ent, npc.actions.stand, {self = ent})