From 88648a68e77fd4346333b8f8bd48917ad8114728 Mon Sep 17 00:00:00 2001
From: Pharap <2933055+Pharap@users.noreply.github.com>
Date: Thu, 26 Sep 2019 09:37:16 +0100
Subject: [PATCH] Add a comment about xorshift (#62)

---
 Minesweeper/Utils/SkullHash.h | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/Minesweeper/Utils/SkullHash.h b/Minesweeper/Utils/SkullHash.h
index 7fdd16f..0ddcf65 100644
--- a/Minesweeper/Utils/SkullHash.h
+++ b/Minesweeper/Utils/SkullHash.h
@@ -20,6 +20,10 @@
 
 struct SkullHash
 {
+	// This is actually part of the algorithm for an 'Xorshift' PRNG variant.
+	// PRNG algorithms that have a single-value state can be easily repurposed as hash functions.
+	// The shift values are taken from page 4 of George Marsaglia's 'Xorshift RNGs'.
+	// Marsaglia's 'Xorshift RNGs': https://www.jstatsoft.org/article/view/v008i14
 	static uint32_t hash(uint32_t value)
 	{
 		value ^= (value << 13);