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(svn r11523) -Codechange: Move the CHANCE macros to core/random_func.cpp cause they depend on Random()

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-Codechange: Convert the CHANCE macros to functions and rename them fitting to the naming style
This commit is contained in:
skidd13
2007-11-25 15:35:25 +00:00
parent 2bf2be987d
commit bdc7fd2d76
13 changed files with 100 additions and 90 deletions
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49
src/macros.h
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@@ -261,55 +261,6 @@ template<typename T> static inline uint CountBits(T value)
return num;
}
/**
* Flips a coin with a given probability.
*
* This macro can be used to get true or false randomized according to a
* given probability. The parameter a and b create a percent value with
* (a/b). The macro returns true in (a/b) percent.
*
* @param a The numerator of the fraction
* @param b The denominator of the fraction, must of course not be null
* @return True in (a/b) percent
*/
#define CHANCE16(a, b) CHANCE16I(a, b, Random())
/**
* Flips a coin with a given probability and saves the randomize-number in a variable.
*
* This macro uses the same parameters as the CHANCE16 marco. The third parameter
* must be a variable the randomize-number from Random() is saved in.
*
* The low 16 bits of r will already be used and can therefor not be passed to
* CHANCE16I. One can only send the high 16 bits to CHANCE16I.
*
* @param a The numerator of the fraction, see CHANCE16
* @param b The denominator of the fraction, see CHANCE16
* @param r The variable to save the randomize-number from Random()
* @return True in (a/b) percent
*/
#define CHANCE16R(a, b, r) CHANCE16I(a, b, r = Random())
/**
* Checks if a given randomize-number is below a given probability.
*
* This macro is used to check if the given probability by the fraction of (a/b)
* is greater than low 16 bits of the given randomize-number v.
*
* Do not use this function twice on the same random 16 bits as it will yield
* the same result. One can use a random number for two calls to CHANCE16I,
* where one call sends the low 16 bits and the other the high 16 bits.
*
* @param a The numerator of the fraction, see CHANCE16
* @param b The denominator of the fraction, see CHANCE16
* @param r The given randomize-number
* @return True if v is less or equals (a/b)
*/
static inline bool CHANCE16I(const uint a, const uint b, const uint32 r)
{
return (uint16)r < (uint16)((65536 * a) / b);
}
#define for_each_bit(_i, _b) \
for (_i = 0; _b != 0; _i++, _b >>= 1) \