raze-gles/source/common/utility/templates.h
2020-04-12 08:30:39 +02:00

146 lines
3.9 KiB
C++

/*
** templates.h
** Some useful template functions
**
**---------------------------------------------------------------------------
** Copyright 1998-2006 Randy Heit
** All rights reserved.
**
** Redistribution and use in source and binary forms, with or without
** modification, are permitted provided that the following conditions
** are met:
**
** 1. Redistributions of source code must retain the above copyright
** notice, this list of conditions and the following disclaimer.
** 2. Redistributions in binary form must reproduce the above copyright
** notice, this list of conditions and the following disclaimer in the
** documentation and/or other materials provided with the distribution.
** 3. The name of the author may not be used to endorse or promote products
** derived from this software without specific prior written permission.
**
** THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
** IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
** OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
** IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
** INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
** NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
** DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
** THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
** (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
** THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
**---------------------------------------------------------------------------
**
*/
#ifndef __TEMPLATES_H__
#define __TEMPLATES_H__
#ifdef _MSC_VER
#pragma once
#endif
#include <stdlib.h>
#include <utility>
#include <algorithm>
//==========================================================================
//
// BinarySearch
//
// Searches an array sorted in ascending order for an element matching
// the desired key.
//
// Template parameters:
// ClassType - The class to be searched
// KeyType - The type of the key contained in the class
//
// Function parameters:
// first - Pointer to the first element in the array
// max - The number of elements in the array
// keyptr - Pointer to the key member of ClassType
// key - The key value to look for
//
// Returns:
// A pointer to the element with a matching key or NULL if none found.
//==========================================================================
template<class ClassType, class KeyType>
inline
const ClassType *BinarySearch (const ClassType *first, int max,
const KeyType ClassType::*keyptr, const KeyType key)
{
int min = 0;
--max;
while (min <= max)
{
int mid = (min + max) / 2;
const ClassType *probe = &first[mid];
const KeyType &seekey = probe->*keyptr;
if (seekey == key)
{
return probe;
}
else if (seekey < key)
{
min = mid + 1;
}
else
{
max = mid - 1;
}
}
return NULL;
}
//==========================================================================
//
// MIN
//
// Returns the minimum of a and b.
//==========================================================================
#ifdef MIN
#undef MIN
#endif
template<class T>
inline
const T MIN (const T a, const T b)
{
return a < b ? a : b;
}
//==========================================================================
//
// MAX
//
// Returns the maximum of a and b.
//==========================================================================
#ifdef MAX
#undef MAX
#endif
template<class T>
inline
const T MAX (const T a, const T b)
{
return a > b ? a : b;
}
//==========================================================================
//
// clamp
//
// Clamps in to the range [min,max].
//==========================================================================
template<class T>
inline
T clamp (const T in, const T min, const T max)
{
return in <= min ? min : in >= max ? max : in;
}
#endif //__TEMPLATES_H__