From 866b09992668f97af063dcd77dc5dd0e3a512b94 Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?Andr=C3=A9=20Nusser?= Date: Thu, 24 Mar 2016 00:11:28 +0100 Subject: New Random class for convenient random number generation. --- src/Makefile.am.drumgizmo | 1 + src/instrument.cc | 8 +++--- src/instrument.h | 3 +++ src/powerlist.cc | 14 +---------- src/powerlist.h | 3 +++ src/random.cc | 58 ++++++++++++++++++++++++++++++++++++++++++++ src/random.h | 62 +++++++++++++++++++++++++++++++++++++++++++++++ src/velocity.cc | 2 +- src/velocity.h | 3 +++ 9 files changed, 135 insertions(+), 19 deletions(-) create mode 100644 src/random.cc create mode 100644 src/random.h (limited to 'src') diff --git a/src/Makefile.am.drumgizmo b/src/Makefile.am.drumgizmo index e41bacc..8f648d0 100644 --- a/src/Makefile.am.drumgizmo +++ b/src/Makefile.am.drumgizmo @@ -28,6 +28,7 @@ DRUMGIZMO_SOURCES = \ $(top_srcdir)/src/mutex.cc \ $(top_srcdir)/src/path.cc \ $(top_srcdir)/src/powerlist.cc \ + $(top_srcdir)/src/random.cc \ $(top_srcdir)/src/sample.cc \ $(top_srcdir)/src/semaphore.cc \ $(top_srcdir)/src/saxparser.cc \ diff --git a/src/instrument.cc b/src/instrument.cc index 96a6bfd..21371f0 100644 --- a/src/instrument.cc +++ b/src/instrument.cc @@ -70,9 +70,8 @@ Sample *Instrument::sample(level_t level, size_t pos) } if(Conf::enable_velocity_randomiser) { - float r = (float)rand() / (float)RAND_MAX; // random number: [0;1] - r -= 0.5; // random number [-0.5;0.5] - r *= Conf::velocity_randomiser_weight * 2; // ex. random number [-0.1;0.1] + float r = rand.floatInRange(-1.0*Conf::velocity_randomiser_weight, + Conf::velocity_randomiser_weight); level += r; if(level > 1.0) level = 1.0; if(level < 0.0) level = 0.0; @@ -91,8 +90,7 @@ Sample *Instrument::sample(level_t level, size_t pos) // Version 1.0 std::vector s = samples.get(level * mod); if(s.size() == 0) return NULL; - size_t idx = rand()%(s.size()); - sample = s[idx]; + sample = rand.choose(s); } if(Conf::enable_velocity_modifier) { diff --git a/src/instrument.h b/src/instrument.h index e880d8d..62f8d01 100644 --- a/src/instrument.h +++ b/src/instrument.h @@ -35,6 +35,7 @@ #include "sample.h" #include "versionstr.h" +#include "random.h" class InstrumentParser; class Instrument { @@ -76,6 +77,8 @@ private: size_t lastpos; float mod; + + Random rand; }; //typedef std::map< std::string, Instrument > Instruments; diff --git a/src/powerlist.cc b/src/powerlist.cc index efb1f97..b6640e9 100644 --- a/src/powerlist.cc +++ b/src/powerlist.cc @@ -51,18 +51,6 @@ #define SIZE 500 -// Box–Muller transform. -// See: http://en.wikipedia.org/wiki/Box%E2%80%93Muller_transform -static float box_muller_transform(float mean, float stddev) -{ - float U1 = (float)rand() / (float)RAND_MAX; - float U2 = (float)rand() / (float)RAND_MAX; - - float x = sqrt(-2.0 * log(U1)) * cos(2.0 * M_PI * U2); - - return mean + stddev * x; -} - PowerList::PowerList() { power_max = 0; @@ -242,7 +230,7 @@ Sample *PowerList::get(level_t level) again: // Select normal distributed value between // (stddev/2) and (power_span-stddev/2) - float lvl = box_muller_transform(mean, stddev); + float lvl = rand.normalDistribution(mean, stddev); // Adjust this value to be in range // (power_min+stddev/2) and (power_max-stddev/2) diff --git a/src/powerlist.h b/src/powerlist.h index 43f51d2..1077d8c 100644 --- a/src/powerlist.h +++ b/src/powerlist.h @@ -30,6 +30,7 @@ #include #include "sample.h" +#include "random.h" class PowerList { public: @@ -47,6 +48,8 @@ private: float power; }; + Random rand; + std::vector samples; float power_max; float power_min; diff --git a/src/random.cc b/src/random.cc new file mode 100644 index 0000000..1df9a62 --- /dev/null +++ b/src/random.cc @@ -0,0 +1,58 @@ +/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */ +/*************************************************************************** + * random.cc + * + * Wed Mar 23 19:17:24 CET 2016 + * Copyright 2016 André Nusser + * andre.nusser@googlemail.com + ****************************************************************************/ + +/* + * This file is part of DrumGizmo. + * + * DrumGizmo is free software; you can redistribute it and/or modify + * it under the terms of the GNU Lesser General Public License as published by + * the Free Software Foundation; either version 3 of the License, or + * (at your option) any later version. + * + * DrumGizmo is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU Lesser General Public License for more details. + * + * You should have received a copy of the GNU Lesser General Public License + * along with DrumGizmo; if not, write to the Free Software + * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA. + */ +#include "random.h" + +#include + +Random::Random() + : Random(std::chrono::system_clock::now().time_since_epoch().count()) +{ + +} + +Random::Random(unsigned int seed) +{ + generator.seed(seed); +} + +int Random::intInRange(int lower_bound, int upper_bound) +{ + std::uniform_int_distribution distribution(lower_bound, upper_bound); + return distribution(generator); +} + +float Random::floatInRange(float lower_bound, float upper_bound) +{ + std::uniform_real_distribution distribution(lower_bound, upper_bound); + return distribution(generator); +} + +float Random::normalDistribution(float mean, float stddev) +{ + std::normal_distribution distribution(mean, stddev); + return distribution(generator); +} diff --git a/src/random.h b/src/random.h new file mode 100644 index 0000000..9eaefad --- /dev/null +++ b/src/random.h @@ -0,0 +1,62 @@ +/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */ +/*************************************************************************** + * random.h + * + * Wed Mar 23 19:17:24 CET 2016 + * Copyright 2016 André Nusser + * andre.nusser@googlemail.com + ****************************************************************************/ + +/* + * This file is part of DrumGizmo. + * + * DrumGizmo is free software; you can redistribute it and/or modify + * it under the terms of the GNU Lesser General Public License as published by + * the Free Software Foundation; either version 3 of the License, or + * (at your option) any later version. + * + * DrumGizmo is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU Lesser General Public License for more details. + * + * You should have received a copy of the GNU Lesser General Public License + * along with DrumGizmo; if not, write to the Free Software + * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA. + */ +#pragma once + +#include +#include + +class Random +{ +public: + Random(); + Random(unsigned int seed); + + //! \return random int in range [, ]. + int intInRange(int lower_bound, int upper_bound); + + //! \return random float in range [, ]. + float floatInRange(float lower_bound, float upper_bound); + + //! \return random float drawn from a normal distribution with mean + //! and standard deviation . + float normalDistribution(float mean, float stddev); + + //! \return uniformly at random chosen element from . + template + T& choose(std::vector& vec); + +private: + std::default_random_engine generator; +}; + +template +T& Random::choose(std::vector& vec) +{ + std::uniform_int_distribution distribution(0, vec.size()-1); + size_t rand_index = distribution(generator); + return vec[rand_index]; +} diff --git a/src/velocity.cc b/src/velocity.cc index 04d0475..0ee00df 100644 --- a/src/velocity.cc +++ b/src/velocity.cc @@ -47,7 +47,7 @@ Sample *Velocity::getSample() { Sample *sample = NULL; - float x = (float)rand() / (float)RAND_MAX; + float x = rand.floatInRange(0, 1); float sum = 0.0; Samples::iterator i = samples.begin(); diff --git a/src/velocity.h b/src/velocity.h index 439ca68..c62ddad 100644 --- a/src/velocity.h +++ b/src/velocity.h @@ -30,6 +30,7 @@ #include #include "sample.h" +#include "random.h" class Velocity { public: @@ -44,6 +45,8 @@ public: private: typedef std::map< Sample *, float > Samples; Samples samples; + + Random rand; }; #endif/*__DRUMGIZMO_VELOCITY_H__*/ -- cgit v1.2.3