Initial commit

2026-04-03 00:22:39 -05:00
commit eca1e8c458
945 changed files with 218160 additions and 0 deletions
--- a/libsst-random/SST_CMWC.c
+++ b/libsst-random/SST_CMWC.c
@@ -0,0 +1,121 @@
+/*
+	SST_CMWC.c
+	Author: Chris Ertel <crertel@762studios.com>
+	Created: 2/26/2012
+
+	Purpose: 
+
+	Implementation of complimentary multiply with carry algorithm
+
+	License:
+
+	This program is free software. It comes without any warranty, to
+	the extent permitted by applicable law. You can redistribute it
+	and/or modify it under the terms of the Do What The Fuck You Want
+	To Public License, Version 2, as published by Sam Hocevar. See
+	http://sam.zoy.org/wtfpl/COPYING for more details.
+*/
+
+#include "RandomFuncTbl.h"
+
+/* Do you believe in magic? */
+#define PHI 0x9e3779b9
+#define CMWC_SIZE 4096
+
+/* CMWC Data Struct */
+typedef struct SST_CMWC_Private
+{
+	uint32_t cmwc_buffer[CMWC_SIZE];
+	uint32_t cmwc_carry;
+	size_t cmwc_index;
+} SST_CMWC_Private;
+
+/*************************************************************************/
+
+static int cmwc_random(SST_CMWC_Private* cmwc)
+{
+	uint64_t t, a = (uint64_t)18782;
+	uint32_t x, r = 0xfffffffe;
+	
+	cmwc->cmwc_index = (cmwc->cmwc_index + 1) % CMWC_SIZE;
+	t = a * cmwc->cmwc_buffer[cmwc->cmwc_index] + cmwc->cmwc_carry;
+	cmwc->cmwc_carry = (uint32_t)(t >> 32);
+	x = (uint32_t)(t + cmwc->cmwc_carry);
+
+	if (x < cmwc->cmwc_carry) 
+	{
+		x++;
+		cmwc->cmwc_carry++;
+	}
+
+	cmwc->cmwc_buffer[cmwc->cmwc_index] = r - x;
+	
+	return (int)cmwc->cmwc_buffer[cmwc->cmwc_index];
+}
+
+/*************************************************************************/
+
+static void CMWC_InitFromSeed(void* priv, uint32_t seed)
+{
+	SST_CMWC_Private* cmwc = (SST_CMWC_Private*)priv;
+	size_t i;
+	
+	cmwc->cmwc_index = 4095;
+	cmwc->cmwc_carry = 362436;
+	cmwc->cmwc_buffer[0] = seed;
+	cmwc->cmwc_buffer[1] = seed + PHI;
+	cmwc->cmwc_buffer[2] = seed + PHI + PHI;
+
+	for (i = 3; i < CMWC_SIZE; i++)
+		cmwc->cmwc_buffer[i] = cmwc->cmwc_buffer[i - 3] ^ cmwc->cmwc_buffer[i - 2] ^ PHI ^ (uint32_t)i;
+}
+
+/*************************************************************************/
+
+static void CMWC_GetFloatArray(void* priv, float* _out, size_t _numElements, float _min, float _max)
+{
+	SST_CMWC_Private* cmwc = (SST_CMWC_Private*)priv;
+	size_t i;
+	const float diff = _max - _min;
+	
+	/* compute and return a pseudorandom float in the range */
+	for ( i = 0; i < _numElements; i++ )
+	{
+		_out[i] = _min + randIntToFloat((uint32_t)boundInt(cmwc_random(cmwc), 0, SST_RAND_FLOATBITS_MAX)) * diff; /* x = [0,1];  value = min + x*(max - min) */
+	}
+}
+
+/*************************************************************************/
+
+static int CMWC_GetInt(void* priv)
+{
+	SST_CMWC_Private* cmwc = (SST_CMWC_Private*)priv;
+	
+	return cmwc_random(cmwc);
+}
+
+/*************************************************************************/
+
+static void CMWC_GetIntArray(void* priv, int* _out, size_t _numElements, int _min, int _max)
+{
+	SST_CMWC_Private* cmwc = (SST_CMWC_Private*)priv;
+	size_t i;
+
+	/* grab an number of pseudorandom ints in the specified range */
+	for(i = 0; i < _numElements; i++)
+	{
+		_out[i] = boundInt(cmwc_random(cmwc), _min, _max);
+	}
+}
+
+/*************************************************************************/
+
+/* Function table for CMWC random number generation. */
+const SST_PRNG_FuncTable _SST_CMWCFuncTable = 
+{
+	CMWC_InitFromSeed,
+	CMWC_GetFloatArray,
+	CMWC_GetInt,
+	CMWC_GetIntArray,
+	sizeof(SST_CMWC_Private)
+};