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Code cleanup: remove unused functions from GLideNHQ/TxUtil

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This commit is contained in:
Sergey Lipskiy 2014-12-22 18:52:15 +06:00
parent bb89ec2dff
commit 27cceff526
2 changed files with 0 additions and 80 deletions
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78
GLideNHQ/TxUtil.cpp
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@ -126,84 +126,6 @@ TxUtil::checksum64(uint8 *src, int width, int height, int size, int rowStride, u
return crc64Ret;
}
/*
** Computes Adler32 checksum for a stream of data.
**
** From the specification found in RFC 1950: (ZLIB Compressed Data Format
** Specification version 3.3)
**
** ADLER32 (Adler-32 checksum) This contains a checksum value of the
** uncompressed data (excluding any dictionary data) computed according to
** Adler-32 algorithm. This algorithm is a 32-bit extension and improvement
** of the Fletcher algorithm, used in the ITU-T X.224 / ISO 8073 standard.
**
** Adler-32 is composed of two sums accumulated per byte: s1 is the sum of
** all bytes, s2 is the sum of all s1 values. Both sums are done modulo
** 65521. s1 is initialized to 1, s2 to zero. The Adler-32 checksum is stored
** as s2*65536 + s1 in most-significant-byte first (network) order.
**
** 8.2. The Adler-32 algorithm
**
** The Adler-32 algorithm is much faster than the CRC32 algorithm yet still
** provides an extremely low probability of undetected errors.
**
** The modulo on unsigned long accumulators can be delayed for 5552 bytes,
** so the modulo operation time is negligible. If the bytes are a, b, c,
** the second sum is 3a + 2b + c + 3, and so is position and order sensitive,
** unlike the first sum, which is just a checksum. That 65521 is prime is
** important to avoid a possible large class of two-byte errors that leave
** the check unchanged. (The Fletcher checksum uses 255, which is not prime
** and which also makes the Fletcher check insensitive to single byte
** changes 0 <-> 255.)
**
** The sum s1 is initialized to 1 instead of zero to make the length of
** the sequence part of s2, so that the length does not have to be checked
** separately. (Any sequence of zeroes has a Fletcher checksum of zero.)
*/
uint32
TxUtil::Adler32(const uint8* data, int Len, uint32 dwAdler32)
{
#if 1
/* zlib adler32 */
return adler32(dwAdler32, data, Len);
#else
register uint32 s1 = dwAdler32 & 0xFFFF;
register uint32 s2 = (dwAdler32 >> 16) & 0xFFFF;
int k;
while (Len > 0) {
/* 5552 is the largest n such that 255n(n+1)/2 + (n+1)(BASE-1) <= 2^32-1 */
k = (Len < 5552 ? Len : 5552);
Len -= k;
while (k--) {
s1 += *data++;
s2 += s1;
}
/* 65521 is the largest prime smaller than 65536 */
s1 %= 65521;
s2 %= 65521;
}
return (s2 << 16) | s1;
#endif
}
uint32
TxUtil::Adler32(const uint8* src, int width, int height, int size, int rowStride)
{
int i;
uint32 ret = 1;
uint32 width_in_bytes = width * size;
for (i = 0; i < height; i++) {
ret = Adler32(src, width_in_bytes, ret);
src += rowStride;
}
return ret;
}
/* Rice CRC32 for hires texture packs */
/* NOTE: The following is used in Glide64 to calculate the CRC32
* for Rice hires texture packs.

2
GLideNHQ/TxUtil.h
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@ -36,8 +36,6 @@
class TxUtil
{
private:
uint32 Adler32(const uint8* data, int Len, uint32 Adler);
uint32 Adler32(const uint8* src, int width, int height, int size, int rowStride);
uint32 RiceCRC32(const uint8* src, int width, int height, int size, int rowStride);
boolean RiceCRC32_CI4(const uint8* src, int width, int height, int rowStride,
uint32* crc32, uint32* cimax);