sl@0: /*
sl@0:  * @(#)DeviceTables.cpp 1.5 00/03/15
sl@0:  *
sl@0:  * (C) Copyright IBM Corp. 1998 - 2005 - All Rights Reserved
sl@0:  *
sl@0:  */
sl@0: 
sl@0: #include "LETypes.h"
sl@0: #include "OpenTypeTables.h"
sl@0: #include "DeviceTables.h"
sl@0: #include "LESwaps.h"
sl@0: 
sl@0: U_NAMESPACE_BEGIN
sl@0: 
sl@0: const le_uint16 DeviceTable::fieldMasks[]    = {0x0003, 0x000F, 0x00FF};
sl@0: const le_uint16 DeviceTable::fieldSignBits[] = {0x0002, 0x0008, 0x0080};
sl@0: const le_uint16 DeviceTable::fieldBits[]     = {     2,      4,      8};
sl@0: 
sl@0: le_int16 DeviceTable::getAdjustment(le_uint16 ppem) const
sl@0: {
sl@0:     le_uint16 start = SWAPW(startSize);
sl@0:     le_uint16 format = SWAPW(deltaFormat) - 1;
sl@0:     le_int16 result = 0;
sl@0:     
sl@0:     if (ppem >= start && ppem <= SWAPW(endSize)) {
sl@0:         le_uint16 sizeIndex = ppem - start;
sl@0:         le_uint16 bits = fieldBits[format];
sl@0:         le_uint16 count = 16 / bits;
sl@0:         le_uint16 word = SWAPW(deltaValues[sizeIndex / count]);
sl@0:         le_uint16 fieldIndex = sizeIndex % count;
sl@0:         le_uint16 shift = 16 - (bits * (fieldIndex + 1));
sl@0:         le_uint16 field = (word >> shift) & fieldMasks[format];
sl@0: 
sl@0:         result = field;
sl@0: 
sl@0:         if ((field & fieldSignBits[format]) != 0) {
sl@0:             result |= ~ fieldMasks[format];
sl@0:         }
sl@0:     }
sl@0: 
sl@0:     return result;
sl@0: }
sl@0: 
sl@0: U_NAMESPACE_END