Random Number Generation

Random Number Generation — Random number generation

Synopsis

#define             oil_rand_s32
#define             oil_rand_s16
#define             oil_rand_s8
#define             oil_rand_u32
#define             oil_rand_u16
#define             oil_rand_u8
#define             oil_rand_s64
#define             oil_rand_u64
#define             oil_rand_f32
#define             oil_rand_f64
void                oil_random_alpha                    (oil_type_u8 *dest,
                                                         int n);
void                oil_random_argb                     (oil_type_u32 *dest,
                                                         int n);
void                oil_random_f32                      (oil_type_f32 *dest,
                                                         int n);
void                oil_random_f64                      (oil_type_f64 *dest,
                                                         int n);
void                oil_random_s16                      (oil_type_s16 *dest,
                                                         int n);
void                oil_random_s32                      (oil_type_s32 *dest,
                                                         int n);
void                oil_random_s64                      (oil_type_s64 *dest,
                                                         int n);
void                oil_random_s8                       (oil_type_s8 *dest,
                                                         int n);
void                oil_random_u16                      (oil_type_u16 *dest,
                                                         int n);
void                oil_random_u32                      (oil_type_u32 *dest,
                                                         int n);
void                oil_random_u64                      (oil_type_u64 *dest,
                                                         int n);
void                oil_random_u8                       (oil_type_u8 *dest,
                                                         int n);

Description

Details

oil_rand_s32

#define oil_rand_s32() ((rand()&0xffff)<<16 | (rand()&0xffff))

Evaluates to a random integer in the range [-(1<<31), (1<<31)-1].


oil_rand_s16

#define oil_rand_s16() ((int16_t)(rand()&0xffff))

Evaluates to a random integer in the range [-(1<<15), (1<<15)-1].


oil_rand_s8

#define oil_rand_s8() ((int8_t)(rand()&0xffff))

Evaluates to a random integer in the range [-(1<<7), (1<<7)-1].


oil_rand_u32

#define oil_rand_u32() ((uint32_t)((rand()&0xffff)<<16 | (rand()&0xffff)))

Evaluates to a random integer in the range [0, (1<<32)-1].


oil_rand_u16

#define oil_rand_u16() ((uint16_t)(rand()&0xffff))

Evaluates to a random integer in the range [0, (1<<16)-1].


oil_rand_u8

#define oil_rand_u8() ((uint8_t)(rand()&0xffff))

Evaluates to a random integer in the range [0, (1<<8)-1].


oil_rand_s64

#define oil_rand_s64() ((int64_t)(oil_rand_s32())<<32 | oil_rand_s32())

Evaluates to a random integer in the range [-(1<<63), (1<<63)-1].


oil_rand_u64

#define oil_rand_u64() ((uint64_t)(oil_rand_u32())<<32 | oil_rand_u32())

Evaluates to a random integer in the range [0, (1<<64)-1].


oil_rand_f32

#define oil_rand_f32() (rand()/(RAND_MAX+1.0))

Evaluates to a random single-precision floating point number in the range [0, 1.0).


oil_rand_f64

#define oil_rand_f64() (((rand()/(RAND_MAX+1.0))+rand())/(RAND_MAX+1.0))

Evaluates to a random double-precision floating point number in the range [0, 1.0).


oil_random_alpha ()

void                oil_random_alpha                    (oil_type_u8 *dest,
                                                         int n);

Writes random values in the range [0, 255] to the destination array suitable for alpha values. This is similar to oil_random_u8(), except the values 0 and 255 are strongly favored.

dest :
n :

oil_random_argb ()

void                oil_random_argb                     (oil_type_u32 *dest,
                                                         int n);

Creates valid random RGBA values and places them in the destination array.

dest : destination array.
n : number of values to write.

oil_random_f32 ()

void                oil_random_f32                      (oil_type_f32 *dest,
                                                         int n);

Writes random single-precision floating point values in the range [0, 1.0) to the destination array.

dest :
n :

oil_random_f64 ()

void                oil_random_f64                      (oil_type_f64 *dest,
                                                         int n);

Writes random double-precision floating point values in the range [0, 1.0) to the destination array.

dest :
n :

oil_random_s16 ()

void                oil_random_s16                      (oil_type_s16 *dest,
                                                         int n);

Writes random values in the range [-(1<<15), (1<<15)-1] to the destination array.

dest :
n :

oil_random_s32 ()

void                oil_random_s32                      (oil_type_s32 *dest,
                                                         int n);

Writes random values in the range [-(1<<31), (1<<31)-1] to the destination array.


oil_random_s64 ()

void                oil_random_s64                      (oil_type_s64 *dest,
                                                         int n);

Writes random values in the range [-(1<<63), (1<<63)-1] to the destination array.

dest :
n :

oil_random_s8 ()

void                oil_random_s8                       (oil_type_s8 *dest,
                                                         int n);

Writes random values in the range [-(1<<7), (1<<7)-1] to the destination array.

dest :
n :

oil_random_u16 ()

void                oil_random_u16                      (oil_type_u16 *dest,
                                                         int n);

Writes random values in the range [0, (1<<16)-1] to the destination array.

dest :
n :

oil_random_u32 ()

void                oil_random_u32                      (oil_type_u32 *dest,
                                                         int n);

Writes random values in the range [0, (1<<32)-1] to the destination array.

dest :
n :

oil_random_u64 ()

void                oil_random_u64                      (oil_type_u64 *dest,
                                                         int n);

Writes random values in the range [0, (1<<64)-1] to the destination array.

dest :
n :

oil_random_u8 ()

void                oil_random_u8                       (oil_type_u8 *dest,
                                                         int n);

Writes random values in the range [0, (1<<8)-1] to the destination array.

dest :
n :