random.h: More comments for defer_rand

1 files changed, 10 insertions, 0 deletions

diff --git a/crawl-ref/source/random.h b/crawl-ref/source/random.h
index b4d48639c9..1b71986b4b 100644
--- a/crawl-ref/source/random.h
+++ b/crawl-ref/source/random.h
@@ -57,6 +57,16 @@ public:
 // * The parameter you use on any given call does not matter.
 // * The object stores the fraction, not a specific integer.
 // * random2() is monotonic in its argument.
+
+// Rephrased: The first time any node in the tree has a method called on
+// it, a random float between 0 and 1 (the fraction) is generated and stored,
+// and this float is combined with the method's parameters to arrive at
+// the result.  Calling the same method on the same node with the same
+// parameters will always give the same result, while different parameters
+// or methods will give different results (though they'll all use the same
+// float which was generated by the first method call).  Each node in the
+// tree has it's own float, so the same method+parameters on different
+// nodes will get different results.
 class defer_rand
 {
     std::vector<unsigned long> bits;