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Improved randomness (part 1) (#7882)

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Faster and with no module bias

Removed rnd_init, rnd_uint32 and rnd_uniform
From now on we will only use rnd_value(min, max) for values in range [min, max] and rnd_chance(chance, base) for chances

Fixes #7881
Fixes #7883
Fixes #7884
Fixes #7885

Co-authored-by: Lemongrass3110 <lemongrass@kstp.at>
This commit is contained in:
Lemon
2023-12-20 00:12:15 +01:00
committed by GitHub
parent ad3a2e99eb
commit 7c153416bc
20 changed files with 83 additions and 107 deletions
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36
src/common/random.cpp
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@@ -3,43 +3,9 @@
#include "random.hpp"
#include <random>
std::mt19937 generator;
std::uniform_int_distribution<int32> int31_distribution;
std::uniform_int_distribution<uint32> uint32_distribution;
/// Initializes the random number generator
void rnd_init( void ){
std::random_device device;
generator = std::mt19937( device() );
int31_distribution = std::uniform_int_distribution<int32>( 0, SINT32_MAX );
uint32_distribution = std::uniform_int_distribution<uint32>( 0, UINT32_MAX );
}
std::uniform_int_distribution<int32> int31_distribution = std::uniform_int_distribution<int32>(0, SINT32_MAX);
/// Generates a random number in the interval [0, SINT32_MAX]
int32 rnd( void ){
return int31_distribution( generator );
}
/// Generates a random number in the interval [0, UINT32_MAX]
uint32 rnd_uint32( void ){
return uint32_distribution( generator );
}
/// Generates a random number in the interval [0.0, 1.0)
/// NOTE: interval is open ended, so 1.0 is excluded
double rnd_uniform( void ){
return rnd_uint32() * ( 1.0 / 4294967296.0 );// divided by 2^32
}
/// Generates a random number in the interval [min, max]
/// Returns min if range is invalid.
int32 rnd_value( int32 min, int32 max ){
if( min >= max ){
return min;
}
return min + (int32)( rnd_uniform() * ( max - min + 1 ) );
}