// FastRandomTest.cpp // Tests the randomness of cFastRandom #include "Globals.h" #include "../TestHelpers.h" #include "FastRandom.h" static void TestInts(void) { cFastRandom rnd; int sum = 0; const int BUCKETS = 8; int Counts[BUCKETS] = {0}; const int ITER = 10000; for (int i = 0; i < ITER; i++) { int v = rnd.RandInt(1000); TEST_GREATER_THAN_OR_EQUAL(v, 0); TEST_LESS_THAN_OR_EQUAL(v, 1000); Counts[v % BUCKETS]++; sum += v; } double avg = static_cast(sum) / ITER; LOG("avg: %f", avg); for (int i = 0; i < BUCKETS; i++) { LOG(" bucket %d: %d", i, Counts[i]); } } static void TestFloats(void) { cFastRandom rnd; float sum = 0; const int BUCKETS = 8; int Counts[BUCKETS] = {0}; const int ITER = 10000; for (int i = 0; i < ITER; i++) { float v = rnd.RandReal(1000.0f); TEST_GREATER_THAN_OR_EQUAL(v, 0); TEST_LESS_THAN_OR_EQUAL(v, 1000); Counts[static_cast(v) % BUCKETS]++; sum += v; } sum = sum / ITER; LOG("avg: %f", sum); for (int i = 0; i < BUCKETS; i++) { LOG(" bucket %d: %d", i, Counts[i]); } } /** Checks whether re-creating the cFastRandom class produces the same initial number over and over (#2935) */ static void TestReCreation(void) { const int ITER = 10000; int lastVal = 0; int numSame = 0; int maxNumSame = 0; for (int i = 0; i < ITER; ++i) { cFastRandom rnd; int val = rnd.RandInt(9); if (val == lastVal) { numSame += 1; } else { if (numSame > maxNumSame) { maxNumSame = numSame; } numSame = 0; lastVal = val; } } if (numSame > maxNumSame) { maxNumSame = numSame; } LOG("Out of %d creations, there was a chain of at most %d same numbers generated.", ITER, maxNumSame); } IMPLEMENT_TEST_MAIN("FastRandom", TestInts(); TestFloats(); TestReCreation(); )