blob: 0bbbf18149645e9ada955f6864eeed240701a685 [file] [log] [blame]
/*
* @(#)DeviceTables.cpp 1.5 00/03/15
*
* (C) Copyright IBM Corp. 1998 - 2006 - All Rights Reserved
*
*/
#include "LETypes.h"
#include "OpenTypeTables.h"
#include "DeviceTables.h"
#include "LESwaps.h"
U_NAMESPACE_BEGIN
const le_uint16 DeviceTable::fieldMasks[] = {0x0003, 0x000F, 0x00FF};
const le_uint16 DeviceTable::fieldSignBits[] = {0x0002, 0x0008, 0x0080};
const le_uint16 DeviceTable::fieldBits[] = { 2, 4, 8};
#define FORMAT_COUNT LE_ARRAY_SIZE(fieldBits)
le_int16 DeviceTable::getAdjustment(le_uint16 ppem) const
{
le_uint16 start = SWAPW(startSize);
le_uint16 format = SWAPW(deltaFormat) - 1;
le_int16 result = 0;
if (ppem >= start && ppem <= SWAPW(endSize) && format < FORMAT_COUNT) {
le_uint16 sizeIndex = ppem - start;
le_uint16 bits = fieldBits[format];
le_uint16 count = 16 / bits;
le_uint16 word = SWAPW(deltaValues[sizeIndex / count]);
le_uint16 fieldIndex = sizeIndex % count;
le_uint16 shift = 16 - (bits * (fieldIndex + 1));
le_uint16 field = (word >> shift) & fieldMasks[format];
result = field;
if ((field & fieldSignBits[format]) != 0) {
result |= ~ fieldMasks[format];
}
}
return result;
}
U_NAMESPACE_END