From 3c26408a9f1a7af2af8d5364104b285798be8d3f Mon Sep 17 00:00:00 2001
From: simon <simon@journeyman.cc>
Date: Tue, 21 Apr 2015 07:56:22 +0100
Subject: [PATCH] Dememoised get-neighbours, as the optimisation only works in
deep recursion which I'm no longer doing.
---
src/mw_engine/utils.clj | 55 ++++++++++++++++++++++++-----------------
1 file changed, 33 insertions(+), 22 deletions(-)
diff --git a/src/mw_engine/utils.clj b/src/mw_engine/utils.clj
index 3ad2b1f..279ec18 100644
--- a/src/mw_engine/utils.clj
+++ b/src/mw_engine/utils.clj
@@ -1,4 +1,4 @@
-;; Utility functions needed by MicroWorld and, specifically, in the
+;; Utility functions needed by MicroWorld and, specifically, in the
;; interpretation of MicroWorld rule.
(ns mw-engine.utils
@@ -21,17 +21,17 @@
[elt col] (some #(= elt %) col))
(defn get-int-or-zero
- "Return the value of this `property` from this `map` if it is a integer;
+ "Return the value of this `property` from this `map` if it is a integer;
otherwise return zero."
[map property]
(let [value (map property)]
(if (integer? value) value 0)))
-(defn init-generation
+(defn init-generation
"Return a cell like this `cell`, but having a value for :generation, zero if
the cell passed had no integer value for generation, otherwise the value
- taken from the cell passed. The `world` argument is present only for
- consistency with the rule engine and is ignored."
+ taken from the cell passed. The `world` argument is present only for
+ consistency with the rule engine and is ignored."
[world cell]
(merge cell {:generation (get-int-or-zero cell :generation)}))
@@ -124,7 +124,10 @@
(get-int cell species))
(def memo-get-neighbours
- "Memoised core primitive for `get-neighbours` for efficiency."
+ "Memoised get neighbours is more efficient when running deeply recursive
+ algorithms on the same world. But it's less efficient when running the
+ engine in its normal iterative style, because then we will rarely call
+ get naighbours on the same cell of the same world twice."
(memoize
(fn [world x y depth]
(remove nil?
@@ -135,28 +138,36 @@
(range (- y depth) (+ y depth 1)))))))))
(defn get-neighbours
- "Get the neighbours to distance depth of the cell at x, y in this world.
+ "Get the neighbours to distance depth of a cell in this world.
+
+ Several overloads:
+ * `world` a world, as described in world.clj;
+ * `cell` a cell within that world
+ Gets immediate neighbours of the specified cell.
+
+ * `world` a world, as described in world.clj;
+ * `cell` a cell within that world
+ * `depth` an integer representing the depth to search from the
+ `cell`
+ Gets neighbours within the specified distance of the cell.
* `world` a world, as described in world.clj;
* `x` an integer representing an x coordinate in that world;
* `y` an integer representing an y coordinate in that world;
* `depth` an integer representing the distance from [x,y] that
- should be searched."
+ should be searched
+ Gets the neighbours within the specified distance of the cell at
+ coordinates [x,y] in this world."
([world x y depth]
- (memo-get-neighbours world x y depth))
+ (remove nil?
+ (map #(get-cell world (first %) (first (rest %)))
+ (remove #(= % (list x y))
+ (combo/cartesian-product
+ (range (- x depth) (+ x depth 1))
+ (range (- y depth) (+ y depth 1)))))))
([world cell depth]
- "Get the neighbours to distance depth of this cell in this world.
-
- * `world` a world, as described in world.clj;
- * `cell` a cell within that world;
- * `depth` an integer representing the distance from [x,y] that
- should be searched."
(memo-get-neighbours world (:x cell) (:y cell) depth))
([world cell]
- "Get the immediate neighbours of this cell in this world
-
- * `world` a world, as described in world.clj;
- * `cell` a cell within that world."
(get-neighbours world cell 1)))
(defn get-neighbours-with-property-value
@@ -166,10 +177,10 @@
* `world` a world, as described in `world.clj`;
* `cell` a cell within that world;
* `depth` an integer representing the distance from [x,y] that
- should be searched;
+ should be searched (optional);
* `property` a keyword representing a property of the neighbours;
* `value` a value of that property (or, possibly, the name of another);
- * `op` a comparator function to use in place of `=`.
+ * `op` a comparator function to use in place of `=` (optional).
It gets messy."
([world x y depth property value op]
@@ -253,7 +264,7 @@
[world cell]
(if (in-bounds world (:x cell) (:y cell))
(map-world world
- #(if
+ #(if
(and
(= (:x cell)(:x %2))
(= (:y cell)(:y %2)))