100 lines
1.9 KiB
C++
100 lines
1.9 KiB
C++
/*
|
|
**********************************************************************
|
|
* Copyright (C) 2002-2003, International Business Machines
|
|
* Corporation and others. All Rights Reserved.
|
|
**********************************************************************
|
|
*/
|
|
|
|
#include "layout/LETypes.h"
|
|
#include "LXUtilities.h"
|
|
|
|
U_NAMESPACE_BEGIN
|
|
|
|
//
|
|
// Finds the high bit by binary searching
|
|
// through the bits in n.
|
|
//
|
|
le_int8 LXUtilities::highBit(le_int32 value)
|
|
{
|
|
if (value <= 0) {
|
|
return -32;
|
|
}
|
|
|
|
le_int8 bit = 0;
|
|
|
|
if (value >= 1 << 16) {
|
|
value >>= 16;
|
|
bit += 16;
|
|
}
|
|
|
|
if (value >= 1 << 8) {
|
|
value >>= 8;
|
|
bit += 8;
|
|
}
|
|
|
|
if (value >= 1 << 4) {
|
|
value >>= 4;
|
|
bit += 4;
|
|
}
|
|
|
|
if (value >= 1 << 2) {
|
|
value >>= 2;
|
|
bit += 2;
|
|
}
|
|
|
|
if (value >= 1 << 1) {
|
|
value >>= 1;
|
|
bit += 1;
|
|
}
|
|
|
|
return bit;
|
|
}
|
|
|
|
le_int32 LXUtilities::search(le_int32 value, const le_int32 array[], le_int32 count)
|
|
{
|
|
le_int32 power = 1 << highBit(count);
|
|
le_int32 extra = count - power;
|
|
le_int32 probe = power;
|
|
le_int32 index = 0;
|
|
|
|
if (value >= array[extra]) {
|
|
index = extra;
|
|
}
|
|
|
|
while (probe > (1 << 0)) {
|
|
probe >>= 1;
|
|
|
|
if (value >= array[index + probe]) {
|
|
index += probe;
|
|
}
|
|
}
|
|
|
|
return index;
|
|
}
|
|
|
|
void LXUtilities::reverse(le_int32 array[], le_int32 length)
|
|
{
|
|
le_int32 front, back;
|
|
|
|
for (front = 0, back = length - 1; front < back; front += 1, back -= 1) {
|
|
le_int32 swap = array[front];
|
|
|
|
array[front] = array[back];
|
|
array[back] = swap;
|
|
}
|
|
}
|
|
|
|
void LXUtilities::reverse(float array[], le_int32 length)
|
|
{
|
|
le_int32 front, back;
|
|
|
|
for (front = 0, back = length - 1; front < back; front += 1, back -= 1) {
|
|
float swap = array[front];
|
|
|
|
array[front] = array[back];
|
|
array[back] = swap;
|
|
}
|
|
}
|
|
|
|
U_NAMESPACE_END
|