Implements cellular automata, closes #13

scripts/algorithms/cellular_auotmata.lua

@@ -1,11 +1,83 @@
-CellularAutomata = {}
+CellularAutomata = {
+    map_w = 0,
+    map_h = 0,
+    iterations = 0,
+}
+
+function CellularAutomata.get_neighbors(map, x, y)
+    local min_x = math.max(0, x-1)
+    local min_y = math.max(0, y-1)
+    local max_x = math.min(x+1, map:get_width()-1)
+    local max_y = math.min(y+1, map:get_height()-1)
+    local result = {}
+    for mx = min_x, max_x do
+        for my = min_y, max_y do
+            table.insert(result, {x = mx, y = my})
+        end
+    end
+    return result
+end
 
 function CellularAutomata:initialize(w, h)
-
+    self.map_w = w
+    self.map_h = h
+    self.iterations = 3
+    math.randomseed()
+    for mx = 0, w-1 do
+        for my = 0, h-1 do
+            local is_wall = math.random(0, 1) == 1
+            if is_wall then
+                visualizer.map:draw_wall(mx, my)
+            else
+                visualizer.map:draw_floor(mx, my)
+            end
+        end
+    end
 end
 
 function CellularAutomata:update()
-    return true
+    if self.iterations <= 0 then
+        return true
+    end
+
+    local old_map = visualizer.map
+    local new_map = old_map:clone()
+
+    for mx = 0, self.map_w - 1 do
+        for my = 0, self.map_h - 1 do
+            local neighbors = self.get_neighbors(old_map, mx, my)
+            local walls = 0
+            local required_walls = 5
+            --print(old_map:is_wall(mx, my))
+            --print(new_map:is_wall(mx, my))
+            for k,v in ipairs(neighbors) do
+                if old_map:is_wall(v.x, v.y) then
+                    walls = walls + 1
+                end
+            end
+            if walls >= required_walls then
+                new_map:draw_wall(mx, my)
+            else
+                new_map:draw_floor(mx, my)
+            end
+            --print(old_map:is_wall(mx, my))
+            --print(new_map:is_wall(mx, my))
+        end
+    end
+
+    -- Now draw the new map onto the existing one
+    for mx = 0, self.map_w - 1 do
+        for my = 0, self.map_h - 1 do
+            if new_map:is_wall(mx, my) then
+                old_map:draw_wall(mx, my)
+            else
+                old_map:draw_floor(mx, my)
+            end
+        end
+    end
+
+    self.iterations = self.iterations - 1
+    return false
 end
 
-visualizer.algorithm_manager:register_algorithm("Cellular Automata", function (w, h) CellularAutomata:initialize() end, function () return CellularAutomata:update() end, 1)
+visualizer.algorithm_manager:register_algorithm("Cellular Automata", function (w, h) CellularAutomata:initialize(w, h) end, function () return CellularAutomata:update() end, 1)