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(svn r19652) -Fix: RandomRange() is used for bigger ranges in many cases, so generally extent it to handle 32 bits.

This commit is contained in:
frosch 2010-04-17 11:49:25 +00:00
parent cd20724d20
commit 184fa43df2
5 changed files with 16 additions and 19 deletions
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6
bin/ai/regression/regression.nut
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@ -192,9 +192,9 @@ function Regression::Base()
print(" RandRange(2): " + AIBase.RandRange(2));
print(" RandRange(2): " + AIBase.RandRange(2));
print(" RandRange(2): " + AIBase.RandRange(2));
print(" RandRange(9): " + AIBase.RandRange(9));
print(" RandRange(9): " + AIBase.RandRange(9));
print(" RandRange(9): " + AIBase.RandRange(9));
print(" RandRange(1000000): " + AIBase.RandRange(1000000)); // 32 bit tests
print(" RandRange(1000000): " + AIBase.RandRange(1000000));
print(" RandRange(1000000): " + AIBase.RandRange(1000000));
print(" Chance(1, 2): " + AIBase.Chance(1, 2));
print(" Chance(1, 2): " + AIBase.Chance(1, 2));
print(" Chance(1, 2): " + AIBase.Chance(1, 2));

8
bin/ai/regression/regression.txt
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@ -96,10 +96,10 @@
RandRange(1): 0
RandRange(2): 0
RandRange(2): 0
RandRange(2): 1
RandRange(9): 6
RandRange(9): 7
RandRange(9): 4
RandRange(2): 0
RandRange(1000000): 987346
RandRange(1000000): 781750
RandRange(1000000): 191841
Chance(1, 2): true
Chance(1, 2): false
Chance(1, 2): false

9
src/core/random_func.cpp
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@ -24,9 +24,9 @@ uint32 Randomizer::Next()
return this->state[1] = ROR(s, 3) - 1;
}
uint32 Randomizer::Next(uint16 max)
uint32 Randomizer::Next(uint32 max)
{
return GB(this->Next(), 0, 16) * max >> 16;
return ((uint64)this->Next() * (uint64)max) >> 32;
}
void Randomizer::SetSeed(uint32 seed)
@ -55,9 +55,8 @@ uint32 DoRandom(int line, const char *file)
return _random.Next();
}
uint DoRandomRange(uint max, int line, const char *file)
uint32 DoRandomRange(uint32 max, int line, const char *file)
{
assert(max <= UINT16_MAX);
return GB(DoRandom(line, file), 0, 16) * max >> 16;
return ((uint64)DoRandom(line, file) * (uint64)max) >> 32;
}
#endif /* RANDOM_DEBUG */

9
src/core/random_func.hpp
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@ -48,7 +48,7 @@ struct Randomizer {
* @param max the maximum value of the returned random number
* @return the random number
*/
uint32 Next(uint16 max);
uint32 Next(uint32 max);
/**
* (Re)set the state of the random number generator.
@ -92,16 +92,15 @@ void SetRandomSeed(uint32 seed);
#endif
uint32 DoRandom(int line, const char *file);
#define RandomRange(max) DoRandomRange(max, __LINE__, __FILE__)
uint DoRandomRange(uint max, int line, const char *file);
uint32 DoRandomRange(uint32 max, int line, const char *file);
#else
static FORCEINLINE uint32 Random()
{
return _random.Next();
}
static FORCEINLINE uint32 RandomRange(uint max)
static FORCEINLINE uint32 RandomRange(uint32 max)
{
assert(max <= UINT16_MAX);
return _random.Next(max);
}
#endif
@ -111,7 +110,7 @@ static FORCEINLINE uint32 InteractiveRandom()
return _interactive_random.Next();
}
static FORCEINLINE uint32 InteractiveRandomRange(uint16 max)
static FORCEINLINE uint32 InteractiveRandomRange(uint32 max)
{
return _interactive_random.Next(max);
}

3
src/industry_cmd.cpp
View File

@ -1923,8 +1923,7 @@ void GenerateIndustries()
/* Add the remaining industries according to their probabilities */
for (uint i = 0; i < total_amount; i++) {
/* RandomRange() can only deal with 16 bit, which is not enough here. */
uint32 r = ((uint64)Random() * (uint64)total_prob) >> 32;
uint32 r = RandomRange(total_prob);
IndustryType it = 0;
while (it < NUM_INDUSTRYTYPES && r >= industry_probs[it]) {
r -= industry_probs[it];