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#include <iostream.h>
#include "PixelCache.H"
static const unsigned int SIZE = 7;
int
PixelCache::lookup(unsigned int value, unsigned int &index)
{
for (unsigned int i = 0; i < length_; i++)
if (value == buffer_[i])
{
index = i;
if (i)
{
unsigned int target = (i >> 1);
do
{
buffer_[i] = buffer_[i - 1];
i--;
}
while (i > target);
buffer_[target] = value;
}
return 1;
}
insert(value);
return 0;
}
unsigned int
PixelCache::get(unsigned int index)
{
unsigned int result = buffer_[index];
if (index != 0)
{
unsigned int i = index;
unsigned int target = (i >> 1);
do
{
buffer_[i] = buffer_[i - 1];
i--;
}
while (i > target);
buffer_[target] = result;
}
return (unsigned int) result;
}
void
PixelCache::insert(unsigned int value)
{
unsigned int insertionPoint;
if (2 >= length_)
insertionPoint = length_;
else
insertionPoint = 2;
unsigned int start;
if (length_ >= SIZE)
start = SIZE - 1;
else
{
start = length_;
length_++;
}
for (unsigned int k = start; k > insertionPoint; k--)
buffer_[k] = buffer_[k - 1];
buffer_[insertionPoint] = value;
}
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