al_Buffer.hpp

#ifndef INCLUDE_AL_BUFFER_HPP
#define INCLUDE_AL_BUFFER_HPP
 
/*  Allocore --
  Multimedia / virtual environment application class library
 
  Copyright (C) 2009. AlloSphere Research Group, Media Arts & Technology, UCSB.
  Copyright (C) 2012. The Regents of the University of California.
  All rights reserved.
 
  Redistribution and use in source and binary forms, with or without
  modification, are permitted provided that the following conditions are met:
 
    Redistributions of source code must retain the above copyright notice,
    this list of conditions and the following disclaimer.
 
    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.
 
    Neither the name of the University of California nor the names of its
    contributors may be used to endorse or promote products derived from
    this software without specific prior written permission.
 
  THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "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 COPYRIGHT HOLDER OR CONTRIBUTORS 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.
 
 
  File description:
  Variably sized one-dimensional array
 
  File author(s):
  Lance Putnam, 2010, putnam.lance@gmail.com
  Keehong Youn, 2017, younkeehong@gmail.com
 
*/
 
#include <algorithm>
#include <vector>
 
namespace al {
 
#if 0
 
 
template <class T, class Alloc=std::allocator<T> >
class Buffer : protected Alloc{
  typedef Alloc super;
public:
 
  explicit Buffer(int size=0)
  :  mElems(size), mSize(size)
  {}
 
  Buffer(int size, int capacity)
  :  mElems(capacity), mSize(size)
  {}
 
  ~Buffer(){}
 
 
  int capacity() const { return mElems.size(); }    
  int size() const { return mSize; }          
  const T * elems() const { return &mElems[0]; }    
  T * elems(){ return &mElems[0]; }          
 
 
  T& operator[](int i){ return mElems[i]; }
 
  const T& operator[](int i) const { return mElems[i]; }
 
 
  void assign(int n, const T& v){ mElems.assign(n,v); }
 
  T& last(){ return mElems[size()-1]; }
  const T& last() const { return mElems[size()-1]; }
 
  void reset(){ mSize=0; }
 
 
  void resize(int n){
    mElems.resize(n);
    setSize(n);
  }
 
 
  void size(int n){
    if(capacity() < n) resize(n);
    else setSize(n);
  }
 
  void append(const T& v, double growFactor=2){
 
    // Grow array if too small
    if(size() >= capacity()){
      // Copy argument since it may be an element in current memory range
      // which may become invalid after the resize.
      const T vsafecopy = v;
      mElems.resize((size() ? size() : 4)*growFactor);
      super::construct(elems()+size(), vsafecopy);
    }
    else{
      super::construct(elems()+size(), v);
    }
    ++mSize;
  }
  void push_back(const T& v, double growFactor=2) { append(v, growFactor); }
 
 
  void append(const Buffer<T>& src){
    append(src.elems(), src.size());
  }
 
  void append(const T * src, int len){
    int oldsize = size();
    size(size() + len);
    std::copy(src, src + len, mElems.begin() + oldsize);
  }
 
  void repeatLast(){ append(last()); }
 
 
 
  template <int n, bool dup>
  void expand(){
    size(size()*n);
    const int Nd = dup ? n : 1;
    for(int i=size()/n-1; i>=0; --i){
      const T& v = (*this)[i];
      for(int j=0; j<Nd; ++j) Alloc::construct(elems()+n*i+j, v);
    }
  }
 
private:
  std::vector<T, Alloc> mElems;
  int mSize;    // logical size array
 
  void setSize(int n){ mSize=n; }
};
 
#endif
 
 
template <class T, class Alloc = std::allocator<T> >
class RingBuffer : protected Alloc {
 public:
  RingBuffer() : mPos(-1), mFill(0) {}
 
  explicit RingBuffer(unsigned size, const T& v = T()) : mPos(size), mFill(0) {
    resize(size, v);
  }
 
  size_t size() const { return mElems.size(); }
 
  int pos() const { return mPos; }
 
  int fill() const { return mFill; }
 
  T& operator[](int i) { return mElems[i]; }
 
  const T& operator[](int i) const { return mElems[i]; }
 
 
  T& next() {
    if (mFill < size()) ++mFill;
    ++mPos;
    if (pos() == size()) {
      mPos = 0;
    }
    return mElems[pos()];
  }
 
  void write(const T& v) { Alloc::construct(&next(), v); }
 
  T& read(int i) { return mElems[wrapOnce(pos() - i, size())]; }
 
  const T& read(int i) const { return readFrom(pos(), i); }
 
 
  const T& readFrom(int from, int dist) const {
    return mElems[wrapOnce(from - dist, size())];
  }
 
  T& newest() { return mElems[pos()]; }
 
  const T& newest() const { return mElems[pos()]; }
 
  void reset() {
    mPos = size() - 1;
    mFill = 0;
  }
 
 
  void resize(int n, const T& v = T()) {
    mElems.resize(n, v);
    if (mPos >= n) mPos = n - 1;
  }
 
 protected:
  std::vector<T, Alloc> mElems;
  int mPos;
  int mFill;
 
  // Moves value one period closer to interval [0, max)
  static int wrapOnce(int v, int max) {
    if (v < 0) return v + max;
    if (v >= max) return v - max;
    return v;
  }
};
 
 
template <int N, class T>
class ShiftBuffer {
 public:
  ShiftBuffer(const T& v = T()) { assign(v); }
 
  static int size() { return N; }
 
  const T* elems() const { return &mElems[0]; }
 
  T* elems() { return &mElems[0]; }
 
  T& operator[](int i) { return mElems[i]; }
 
  const T& operator[](int i) const { return mElems[i]; }
 
  void operator()(const T& v) {
    for (int i = N - 1; i > 0; --i) mElems[i] = mElems[i - 1];
    mElems[0] = v;
  }
 
  void assign(const T& v) {
    for (int i = 0; i < N; ++i) mElems[i] = v;
  }
 
  void zero() { memset(mElems, 0, N * sizeof(T)); }
 
 protected:
  T mElems[N];
};
 
}  // namespace al
 
#endif