Add lua star, example and documentation.

[lua-star.git] / example / main.lua

diff --git a/example/main.lua b/example/main.lua
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+--[[
+
+   Lua star example - Run with love (https://love2d.org/)
+
+   Copyright 2017 wesley werner <wesley.werner@gmail.com>
+
+   This program is free software: you can redistribute it and/or modify
+   it under the terms of the GNU General Public License as published by
+   the Free Software Foundation, either version 3 of the License, or
+   any later version.
+
+   This program is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+   GNU General Public License for more details.
+
+   You should have received a copy of the GNU General Public License
+   along with this program. If not, see http://www.gnu.org/licenses/.
+
+]]--
+
+local luastar = require("lua-star")
+
+-- a 2D map where true is open and false is blocked
+local map = { }
+local mapsize = 10
+local screensize = 500
+local tilesize = screensize / mapsize
+
+-- path start and end
+local path = nil
+local start = { x = 1, y = 10 }
+local goal = { x = 10, y = 1 }
+
+function love.load()
+
+    love.window.setMode( screensize, screensize )
+
+    -- build an open map
+    for x=1, mapsize do
+        map[x] = {}
+        for y=1, mapsize do
+            map[x][y] = true
+        end
+    end
+
+    requestPath()
+
+end
+
+function love.keypressed(key)
+
+    if key == "escape" then
+        love.event.quit()
+    end
+
+end
+
+function love.draw()
+
+    -- draw walls
+    love.graphics.setColor(255, 255, 255)
+    for x=1, mapsize do
+        for y=1, mapsize do
+            local fillstyle = "line"
+            if map[x][y] == false then fillstyle = "fill" end
+            love.graphics.rectangle(fillstyle, (x-1)*tilesize, (y-1)*tilesize, tilesize, tilesize)
+        end
+    end
+
+    -- draw start and end
+    love.graphics.print("START", (start.x-1) * tilesize, (start.y-1) * tilesize)
+    love.graphics.print("GOAL", (goal.x-1) * tilesize, (goal.y-1) * tilesize)
+
+    -- draw the path
+    if path then
+        for i, p in ipairs(path) do
+            love.graphics.setColor(0, 128, 0)
+            love.graphics.rectangle("fill", (p.x-1)*tilesize, (p.y-1)*tilesize, tilesize, tilesize)
+            love.graphics.setColor(255, 255, 255)
+            love.graphics.print(i, (p.x-1) * tilesize, (p.y-1) * tilesize)
+        end
+    end
+
+end
+
+function love.mousepressed( x, y, button, istouch )
+
+    local dx = math.floor(x / tilesize) + 1
+    local dy = math.floor(y / tilesize) + 1
+    map[dx][dy] = not map[dx][dy]
+    requestPath()
+
+end
+
+function positionIsOpenFunc(x, y)
+
+    -- should return true if the position is open to walk
+    return map[x][y]
+
+end
+
+function requestPath()
+
+    path = luastar:find(mapsize, mapsize, start, goal, positionIsOpenFunc)
+
+end