From 694b9dc5b551ccb5565f6da7a3196513eaa8ae97 Mon Sep 17 00:00:00 2001
From: dashodanger <none@none.com>
Date: Sat, 22 Jun 2024 20:22:41 -0600
Subject: [PATCH] xoshiro RNG tweaks

---
 CMakeLists.txt        |  1 +
 source/sys_xoshiro.cc | 54 ++++++++++++++++++++++++++-----------------
 source/sys_xoshiro.h  | 27 ++++++++++++++++++----
 source/ui_module.cc   |  4 ++--
 4 files changed, 58 insertions(+), 28 deletions(-)

diff --git a/CMakeLists.txt b/CMakeLists.txt
index fe22c0526..387ecf6da 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -125,6 +125,7 @@ add_executable(
   ${OBSIDIAN_SOURCE_FILES}
 )
 
+target_include_directories(obsidian SYSTEM PRIVATE libraries/fastPRNG)
 if(NOT CONSOLE_ONLY)
   target_include_directories(obsidian SYSTEM PRIVATE libraries/fltk)
   target_include_directories(
diff --git a/source/sys_xoshiro.cc b/source/sys_xoshiro.cc
index 82ecebff2..b651bc220 100644
--- a/source/sys_xoshiro.cc
+++ b/source/sys_xoshiro.cc
@@ -1,15 +1,24 @@
-/*
-Xoshiro256 Random Generator
-
-By Dashodanger, 2020
-
-This is meant to be a replacement for the AJ_Random library that
-uses the fastPRNG xoshiro256 implementation for random number generation.
-Usage will be as similar to AJ_Random as possible in order to minimize
-changes in other sections of code.
-*/
-
-#include "../fastPRNG/fastPRNG.h"
+//------------------------------------------------------------------------
+//  RANDOM NUMBER GENERATION (Xoshiro256)
+//------------------------------------------------------------------------
+//
+//  OBSIDIAN Level Maker
+//
+//  Copyright (C) 2020-2024 The OBSIDIAN Team
+//
+//  This program is free software; you can redistribute it and/or
+//  modify it under the terms of the GNU General Public License
+//  as published by the Free Software Foundation; either version 2
+//  of the License, or (at your option) any later version.
+//
+//  This program is distributed in the hope that it will be useful,
+//  but WITHOUT ANY WARRANTY; without even the implied warranty of
+//  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+//  GNU General Public License for more details.
+//
+//------------------------------------------------------------------------
+
+#include "fastPRNG.h"
 
 fastPRNG::fastXS64 xoshiro;
 
@@ -20,12 +29,12 @@ void xoshiro_Reseed(uint64_t newseed)
 
 uint64_t xoshiro_UInt()
 {
-    int64_t rand_num = (int64_t)(xoshiro.xoshiro256p());
-    if (rand_num >= 0)
-    {
-        return rand_num;
-    }
-    return -rand_num;
+    return xoshiro.xoshiro256p();
+}
+
+float xoshiro_Float()
+{
+    return xoshiro.xoshiro256p_UNI<float>();
 }
 
 double xoshiro_Double()
@@ -33,9 +42,12 @@ double xoshiro_Double()
     return xoshiro.xoshiro256p_UNI<double>();
 }
 
-// This probably isn't super efficient, but it is rarely used and shouldn't make
-// a huge overall hit to performance - Dasho
 int xoshiro_Between(int low, int high)
 {
-    return (int)(xoshiro.xoshiro256p_Range<float>(low, high));
+    return (int)xoshiro.xoshiro256p_Range<float>(low, high);
+}
+
+double xoshiro_Between(double low, double high)
+{
+    return xoshiro.xoshiro256p_Range<double>(low, high);
 }
diff --git a/source/sys_xoshiro.h b/source/sys_xoshiro.h
index a0408ca14..e5a612da2 100644
--- a/source/sys_xoshiro.h
+++ b/source/sys_xoshiro.h
@@ -1,15 +1,32 @@
-// Xoshiro256 Random Generator
+//------------------------------------------------------------------------
+//  RANDOM NUMBER GENERATION (Xoshiro256)
+//------------------------------------------------------------------------
+//
+//  OBSIDIAN Level Maker
+//
+//  Copyright (C) 2020-2024 The OBSIDIAN Team
+//
+//  This program is free software; you can redistribute it and/or
+//  modify it under the terms of the GNU General Public License
+//  as published by the Free Software Foundation; either version 2
+//  of the License, or (at your option) any later version.
+//
+//  This program is distributed in the hope that it will be useful,
+//  but WITHOUT ANY WARRANTY; without even the implied warranty of
+//  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+//  GNU General Public License for more details.
+//
+//------------------------------------------------------------------------
 
 #pragma once
 
-#include "../../libraries/fastPRNG/fastPRNG.h"
-
-extern fastPRNG::fastXS64 xoshiro;
-
 void xoshiro_Reseed(uint64_t newseed);
 
 uint64_t xoshiro_UInt();
 
+// These return in the range of 0.0f-1.0f/0.0-1.0
+float xoshiro_Float();
 double xoshiro_Double();
 
 int xoshiro_Between(int low, int high);
+double xoshiro_Between(double low, double high);
\ No newline at end of file
diff --git a/source/ui_module.cc b/source/ui_module.cc
index e3b6782fe..6c1513438 100644
--- a/source/ui_module.cc
+++ b/source/ui_module.cc
@@ -595,7 +595,7 @@ void UI_Module::randomize_Values(std::vector<std::string> selected_randomize_gro
                     M->nan_options->do_callback();
                 }
                 M->mod_slider->value(M->mod_slider->round(
-                    xoshiro.xoshiro256p_Range<double>(M->mod_slider->minimum(), M->mod_slider->maximum())));
+                    xoshiro_Between(M->mod_slider->minimum(), M->mod_slider->maximum())));
                 M->mod_slider->do_callback();
                 break;
             }
@@ -610,7 +610,7 @@ void UI_Module::randomize_Values(std::vector<std::string> selected_randomize_gro
         {
             if (StringCompare(group, M->randomize_group) == 0)
             {
-                if (xoshiro.xoshiro256p_UNI<float>() < 0.5)
+                if (xoshiro_Float() < 0.5)
                 {
                     M->mod_check->value(0);
                 }