OpenSceneGraph/include/osgParticle/range
2012-03-21 17:36:20 +00:00

90 lines
2.8 KiB
C++

/* -*-c++-*- OpenSceneGraph - Copyright (C) 1998-2006 Robert Osfield
*
* This library is open source and may be redistributed and/or modified under
* the terms of the OpenSceneGraph Public License (OSGPL) version 0.0 or
* (at your option) any later version. The full license is in LICENSE file
* included with this distribution, and on the openscenegraph.org website.
*
* This library 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
* OpenSceneGraph Public License for more details.
*/
//osgParticle - Copyright (C) 2002 Marco Jez
#ifndef OSGPARTICLE_RANGE
#define OSGPARTICLE_RANGE 1
// include Export simply to disable Visual Studio silly warnings.
#include <osgParticle/Export>
#include <stdlib.h>
#include <osg/Vec2>
#include <osg/Vec3>
#include <osg/Vec4>
namespace osgParticle
{
/**
A simple struct template useful to store ranges of values as min/max pairs.
This struct template helps storing min/max ranges for values of any kind; class <CODE>ValueType</CODE> is
the type of values to be stored, and it must support operations <CODE>ValueType + ValueType</CODE>, <CODE>ValueType - ValueType</CODE>,
and <CODE>ValueType * float</CODE>, otherwise the <CODE>geValueTyperandom()</CODE> method will not compile.
This struct could be extended to customize the random number generator (now it uses only
<CODE>std::rand()</CODE>).
*/
template<class ValueType> struct range
{
/// Lower bound.
ValueType minimum;
/// Higher bound.
ValueType maximum;
/// Construct the object by calling default constructors for min and max.
range() : minimum(ValueType()), maximum(ValueType()) {}
/// Construct and initialize min and max directly.
range(const ValueType& mn, const ValueType& mx) : minimum(mn), maximum(mx) {}
/// Set min and max.
void set(const ValueType& mn, const ValueType& mx) { minimum = mn; maximum = mx; }
/// Get a random value between min and max.
ValueType get_random() const
{
return minimum + (maximum - minimum) * rand() / RAND_MAX;
}
/// Get a random square root value between min and max.
ValueType get_random_sqrtf() const
{
return minimum + (maximum - minimum) * sqrtf( static_cast<float>(rand()) / static_cast<float>(RAND_MAX) );
}
ValueType mid() const
{
return (minimum+maximum)*0.5f;
}
};
/// Range of floats.
typedef range<float> rangef;
/// Range of osg::Vec2s.
typedef range<osg::Vec2> rangev2;
/// Range of osg::Vec3s.
typedef range<osg::Vec3> rangev3;
/// Range of osg::Vec4s.
typedef range<osg::Vec4> rangev4;
}
#endif