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authorAlexander Harkness <bearbin@gmail.com>2013-11-24 15:19:41 +0100
committerAlexander Harkness <bearbin@gmail.com>2013-11-24 15:19:41 +0100
commit675b4aa878f16291ce33fced48a2bc7425f635ae (patch)
tree409914df27a98f65adf866da669429c4de141b6f /source/FastRandom.cpp
parentLineBlockTracer: Using the coord-based block faces. (diff)
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Diffstat (limited to 'source/FastRandom.cpp')
-rw-r--r--source/FastRandom.cpp174
1 files changed, 0 insertions, 174 deletions
diff --git a/source/FastRandom.cpp b/source/FastRandom.cpp
deleted file mode 100644
index 887e4426d..000000000
--- a/source/FastRandom.cpp
+++ /dev/null
@@ -1,174 +0,0 @@
-
-// FastRandom.cpp
-
-// Implements the cFastRandom class representing a fast random number generator
-
-#include "Globals.h"
-#include <time.h>
-#include "FastRandom.h"
-
-
-
-
-
-#if 0 && defined(_DEBUG)
-// Self-test
-// Both ints and floats are quick-tested to see if the random is calculated correctly, checking the range in ASSERTs,
-// and if it performs well in terms of distribution (checked by avg, expected to be in the range midpoint
-class cFastRandomTest
-{
-public:
- cFastRandomTest(void)
- {
- TestInts();
- TestFloats();
- }
-
-
- void TestInts(void)
- {
- printf("Testing ints...\n");
- cFastRandom rnd;
- int sum = 0;
- const int BUCKETS = 8;
- int Counts[BUCKETS];
- memset(Counts, 0, sizeof(Counts));
- const int ITER = 10000;
- for (int i = 0; i < ITER; i++)
- {
- int v = rnd.NextInt(1000);
- ASSERT(v >= 0);
- ASSERT(v < 1000);
- Counts[v % BUCKETS]++;
- sum += v;
- }
- double avg = (double)sum / ITER;
- printf("avg: %f\n", avg);
- for (int i = 0; i < BUCKETS; i++)
- {
- printf(" bucket %d: %d\n", i, Counts[i]);
- }
- }
-
-
- void TestFloats(void)
- {
- printf("Testing floats...\n");
- cFastRandom rnd;
- float sum = 0;
- const int BUCKETS = 8;
- int Counts[BUCKETS];
- memset(Counts, 0, sizeof(Counts));
- const int ITER = 10000;
- for (int i = 0; i < ITER; i++)
- {
- float v = rnd.NextFloat(1000);
- ASSERT(v >= 0);
- ASSERT(v <= 1000);
- Counts[((int)v) % BUCKETS]++;
- sum += v;
- }
- sum = sum / ITER;
- printf("avg: %f\n", sum);
- for (int i = 0; i < BUCKETS; i++)
- {
- printf(" bucket %d: %d\n", i, Counts[i]);
- }
- }
-} g_Test;
-
-#endif
-
-
-
-
-
-
-int cFastRandom::m_SeedCounter = 0;
-
-
-
-
-
-cFastRandom::cFastRandom(void) :
- m_Seed(m_SeedCounter++)
-{
-}
-
-
-
-
-
-int cFastRandom::NextInt(int a_Range)
-{
- ASSERT(a_Range <= 1000000); // The random is not sufficiently linearly distributed with bigger ranges
- ASSERT(a_Range > 0);
-
- // Make the m_Counter operations as minimal as possible, to emulate atomicity
- int Counter = m_Counter++;
-
- // Use a_Range, m_Counter and m_Seed as inputs to the pseudorandom function:
- int n = a_Range + m_Counter * 57 + m_Seed * 57 * 57;
- n = (n << 13) ^ n;
- n = ((n * (n * n * 15731 + 789221) + 1376312589) & 0x7fffffff);
- return ((n / 11) % a_Range);
-}
-
-
-
-
-
-int cFastRandom::NextInt(int a_Range, int a_Salt)
-{
- ASSERT(a_Range <= 1000000); // The random is not sufficiently linearly distributed with bigger ranges
- ASSERT(a_Range > 0);
-
- // Make the m_Counter operations as minimal as possible, to emulate atomicity
- int Counter = m_Counter++;
-
- // Use a_Range, a_Salt, m_Counter and m_Seed as inputs to the pseudorandom function:
- int n = a_Range + m_Counter * 57 + m_Seed * 57 * 57 + a_Salt * 57 * 57 * 57;
- n = (n << 13) ^ n;
- n = ((n * (n * n * 15731 + 789221) + 1376312589) & 0x7fffffff);
- return ((n / 11) % a_Range);
-}
-
-
-
-
-
-float cFastRandom::NextFloat(float a_Range)
-{
- // Make the m_Counter operations as minimal as possible, to emulate atomicity
- int Counter = m_Counter++;
-
- // Use a_Range, a_Salt, m_Counter and m_Seed as inputs to the pseudorandom function:
- int n = (int)a_Range + m_Counter * 57 + m_Seed * 57 * 57;
- n = (n << 13) ^ n;
- n = ((n * (n * n * 15731 + 789221) + 1376312589) & 0x7fffffff);
-
- // Convert the integer into float with the specified range:
- return (((float)n / (float)0x7fffffff) * a_Range);
-}
-
-
-
-
-
-float cFastRandom::NextFloat(float a_Range, int a_Salt)
-{
- // Make the m_Counter operations as minimal as possible, to emulate atomicity
- int Counter = m_Counter++;
-
- // Use a_Range, a_Salt, m_Counter and m_Seed as inputs to the pseudorandom function:
- int n = (int)a_Range + m_Counter * 57 + m_Seed * 57 * 57 + a_Salt * 57 * 57 * 57;
- n = (n << 13) ^ n;
- n = ((n * (n * n * 15731 + 789221) + 1376312589) & 0x7fffffff);
-
- // Convert the integer into float with the specified range:
- return (((float)n / (float)0x7fffffff) * a_Range);
-}
-
-
-
-