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libsfml  1.6+dfsg2
Randomizer.cpp
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00001 
00002 //
00003 // SFML - Simple and Fast Multimedia Library
00004 // Copyright (C) 2007-2009 Laurent Gomila (laurent.gom@gmail.com)
00005 //
00006 // This software is provided 'as-is', without any express or implied warranty.
00007 // In no event will the authors be held liable for any damages arising from the use of this software.
00008 //
00009 // Permission is granted to anyone to use this software for any purpose,
00010 // including commercial applications, and to alter it and redistribute it freely,
00011 // subject to the following restrictions:
00012 //
00013 // 1. The origin of this software must not be misrepresented;
00014 //    you must not claim that you wrote the original software.
00015 //    If you use this software in a product, an acknowledgment
00016 //    in the product documentation would be appreciated but is not required.
00017 //
00018 // 2. Altered source versions must be plainly marked as such,
00019 //    and must not be misrepresented as being the original software.
00020 //
00021 // 3. This notice may not be removed or altered from any source distribution.
00022 //
00024 
00026 // Headers
00028 #include <SFML/System/Randomizer.hpp>
00029 #include <stdlib.h>
00030 #include <time.h>
00031 
00032 
00033 namespace
00034 {
00035     // Set the random numbers sequence seed with the current system time, so that it is always different
00036     unsigned int SetRandomSeed()
00037     {
00038         unsigned int Seed = static_cast<unsigned int>(time(NULL));
00039         srand(Seed);
00040         return Seed;
00041     }
00042 }
00043 
00044 
00045 namespace sf
00046 {
00048 // Static member variables
00050 unsigned int Randomizer::ourSeed = SetRandomSeed();
00051 
00052 
00057 void Randomizer::SetSeed(unsigned int Seed)
00058 {
00059     srand(Seed);
00060     ourSeed = Seed;
00061 }
00062 
00063 
00067 unsigned int Randomizer::GetSeed()
00068 {
00069     return ourSeed;
00070 }
00071 
00072 
00076 float Randomizer::Random(float Begin, float End)
00077 {
00078     // This is not the best algorithm, but it is fast and will be enough in most cases
00079     // (see Google for best approaches)
00080 
00081     return static_cast<float>(rand()) / RAND_MAX * (End - Begin) + Begin;
00082 }
00083 
00084 
00088 int Randomizer::Random(int Begin, int End)
00089 {
00090     // This is not the best algorithm, but it is fast and will be enough in most cases
00091     // (see Google for best approaches)
00092 
00093     return rand() % (End - Begin + 1) + Begin;
00094 }
00095 
00096 } // namespace sf