X-Git-Url: http://git.localhorst.tv/?a=blobdiff_plain;f=src%2Frand%2FGaloisLFSR.hpp;h=f8a61e23f3f7c721689d7e0ff4a2404aa671f412;hb=7570271f7e1ede3ef65808f859597001338a7fe6;hp=b0714432c77eb20e8cdeff74d6b2ce7dc7220f43;hpb=bb83e2c9db0fc9746eb076a0ecbd5c64f899d7eb;p=blank.git diff --git a/src/rand/GaloisLFSR.hpp b/src/rand/GaloisLFSR.hpp index b071443..f8a61e2 100644 --- a/src/rand/GaloisLFSR.hpp +++ b/src/rand/GaloisLFSR.hpp @@ -1,6 +1,7 @@ #ifndef BLANK_RAND_GALOISLFSR_HPP_ #define BLANK_RAND_GALOISLFSR_HPP_ +#include #include #include @@ -42,12 +43,36 @@ public: return out = static_cast(state); } + /// special case for randrom(boolean), since static_cast(0b10) == true + bool operator ()(bool &out) noexcept { + return out = operator ()(); + } + template T Next() noexcept { T next; return (*this)(next); } + float SNorm() noexcept { + return float(Next()) * (1.0f / 2147483647.5f) - 1.0f; + } + + float UNorm() noexcept { + return float(Next()) * (1.0f / 4294967295.0f); + } + + template + typename Container::reference From(Container &c) { + assert(c.size() > 0); + return c[Next() % c.size()]; + } + template + typename Container::const_reference From(const Container &c) { + assert(c.size() > 0); + return c[Next() % c.size()]; + } + private: std::uint64_t state; // bits 64, 63, 61, and 60 set to 1 (counting from 1 lo to hi)