random8.h

Go to the documentation of this file.

#ifndef __INC_LIB8TION_RANDOM_H
#define __INC_LIB8TION_RANDOM_H
 
#include <stdint.h>
 
#include "lib8tion/lib8static.h"
 
 
 
 
#define FASTLED_RAND16_2053 ((uint16_t)(2053))
#define FASTLED_RAND16_13849 ((uint16_t)(13849))
 
#if defined(LIB8_ATTINY)
#define APPLY_FASTLED_RAND16_2053(x) (x << 11) + (x << 2) + x
#else
#define APPLY_FASTLED_RAND16_2053(x) (x * FASTLED_RAND16_2053)
#endif
 
extern uint16_t rand16seed; // = RAND16_SEED;
 
LIB8STATIC uint8_t random8() {
    rand16seed = APPLY_FASTLED_RAND16_2053(rand16seed) + FASTLED_RAND16_13849;
    // return the sum of the high and low bytes, for better
    //  mixing and non-sequential correlation
    return (uint8_t)(((uint8_t)(rand16seed & 0xFF)) +
                     ((uint8_t)(rand16seed >> 8)));
}
 
LIB8STATIC uint16_t random16() {
    rand16seed = APPLY_FASTLED_RAND16_2053(rand16seed) + FASTLED_RAND16_13849;
    return rand16seed;
}
 
LIB8STATIC uint8_t random8(uint8_t lim) {
    uint8_t r = random8();
    r = (r * lim) >> 8;
    return r;
}
 
LIB8STATIC uint8_t random8(uint8_t min, uint8_t lim) {
    uint8_t delta = lim - min;
    uint8_t r = random8(delta) + min;
    return r;
}
 
LIB8STATIC uint16_t random16(uint16_t lim) {
    uint16_t r = random16();
    uint32_t p = (uint32_t)lim * (uint32_t)r;
    r = p >> 16;
    return r;
}
 
LIB8STATIC uint16_t random16(uint16_t min, uint16_t lim) {
    uint16_t delta = lim - min;
    uint16_t r = random16(delta) + min;
    return r;
}
 
LIB8STATIC void random16_set_seed(uint16_t seed) { rand16seed = seed; }
 
LIB8STATIC uint16_t random16_get_seed() { return rand16seed; }
 
LIB8STATIC void random16_add_entropy(uint16_t entropy) {
    rand16seed += entropy;
}
 
 
#endif