From 99bd04578e19ace7bfe75e78a4d38457c5f3d275 Mon Sep 17 00:00:00 2001
From: grilledham <jrdgillham@gmail.com>
Date: Tue, 12 Jun 2018 17:24:59 +0100
Subject: [PATCH] added extra functions

---
 map_gen/shared/random.lua | 33 ++++++++++++++++++++++++---------
 1 file changed, 24 insertions(+), 9 deletions(-)

diff --git a/map_gen/shared/random.lua b/map_gen/shared/random.lua
index 4e0ad18f..12e9b9ad 100644
--- a/map_gen/shared/random.lua
+++ b/map_gen/shared/random.lua
@@ -15,19 +15,18 @@ function Random.new(seed1, seed2)
     return random
 end
 
-local function get_uint(self)
-    self.z = 36969 * bit32.band(self.z, 65535) + bit32.rshift(self.z, 16)
-    self.w = 18000 * bit32.band(self.w, 65535) + bit32.rshift(self.w, 16)
-    local ret = bit32.lshift(self.z, 16) + self.w
-    return bit32.band(ret, 4294967295)
-end
-
 local e = 1 / (2 ^ 32 + 2)
 
 -- return float (0, 1) exclusive
 function Random.next(self)
-    local u = get_uint(self)
-    return (u + 1.0) * e
+    local z, w = self.z, self.w
+    z = 36969 * bit32.band(z, 65535) + bit32.rshift(z, 16)
+    w = 18000 * bit32.band(w, 65535) + bit32.rshift(w, 16)
+    self.z, self.w = z, w
+
+    local ret = bit32.lshift(z, 16) + w
+    ret = bit32.band(ret, 4294967295)
+    return (ret + 1.0) * e
 end
 
 -- returns int [min, max] inclusive
@@ -38,4 +37,20 @@ function Random.next_int(self, min, max)
     return math.floor(u)
 end
 
+function Random.next_from_point(x, y)
+    x = 36969 * bit32.band(x, 65535) + bit32.rshift(x, 16)
+    y = 18000 * bit32.band(y, 65535) + bit32.rshift(y, 16)
+
+    local ret = bit32.lshift(x, 16) + y
+    ret = bit32.band(ret, 4294967295)
+    return (ret + 1.0) * e
+end
+
+function Random.next_int_from_point(x, y, min, max)
+    local u = Random.next_from_point(x, y)
+
+    u = u * (max - min + 1) + min
+    return math.floor(u)
+end
+
 return Random