EsenthalEngine/ThirdPartyLibs/LZHAM/Source/lzham_lzdecompbase.cpp

// File: lzham_lzdecompbase.cpp
// See Copyright Notice and license at the end of include/lzham.h
#include "lzham_core.h"
#include "lzham_lzdecompbase.h"

namespace lzham
{
	// Keep in sync with LZHAM_DEFAULT_ADAPT_RATE, and LZHAM_DEFAULT_TABLE_UPDATE_RATE, etc.
	table_update_settings g_table_update_settings[] =
	{
		{ 4, 32 },   // crazy slow!
		{ 5, 33 },
		{ 6, 34 },
		{ 7, 35 },
		{ 8, 36 },
      
		{ 16, 48 },
		{ 32, 72 },
		{ 64, 64 }, // codec's internal default
		{ 98, 80 },
		{ 128, 96 },
      
		{ 192, 112 },
		{ 256, 128 },
      { 512, 128+16*2 },
      { 1024, 128+16*4 },
      { 2048, 128+16*6 },
      
      { 2048, 128+16*8 },
      { 2048, 128+16*10 },
      { 2048, 128+16*12 },
      { 2048, 128+16*14 },
      { 2048, 128+16*16 }
	};

	uint CLZDecompBase::m_lzx_position_base[CLZDecompBase::cLZXMaxPositionSlots] = 
	{
		0x0, 0x1, 0x2, 0x3, 0x4, 0x6, 0x8, 0xC, 0x10, 0x18, 0x20, 0x30, 0x40, 0x60, 0x80, 0xC0,
		0x100, 0x180, 0x200, 0x300, 0x400, 0x600, 0x800, 0xC00, 0x1000, 0x1800, 0x2000, 0x3000, 0x4000, 0x6000, 0x8000, 0xC000,
		0x10000, 0x18000, 0x20000, 0x30000, 0x40000, 0x60000, 0x80000, 0xC0000, 0x100000, 0x180000, 0x200000, 0x300000, 0x400000, 0x600000, 0x800000, 0xC00000,
		0x1000000, 0x1800000, 0x2000000, 0x3000000, 0x4000000, 0x6000000, 0x8000000, 0xA000000, 0xC000000, 0xE000000, 0x10000000, 0x12000000, 0x14000000, 0x16000000, 0x18000000, 0x1A000000,
		0x1C000000, 0x1E000000, 0x20000000, 0x22000000, 0x24000000, 0x26000000, 0x28000000, 0x2A000000, 0x2C000000, 0x2E000000, 0x30000000, 0x32000000, 0x34000000, 0x36000000, 0x38000000, 0x3A000000,
		0x3C000000, 0x3E000000, 0x40000000, 0x42000000, 0x44000000, 0x46000000, 0x48000000, 0x4A000000, 0x4C000000, 0x4E000000, 0x50000000, 0x52000000, 0x54000000, 0x56000000, 0x58000000, 0x5A000000,
		0x5C000000, 0x5E000000, 0x60000000, 0x62000000, 0x64000000, 0x66000000, 0x68000000, 0x6A000000, 0x6C000000, 0x6E000000, 0x70000000, 0x72000000, 0x74000000, 0x76000000, 0x78000000, 0x7A000000,
		0x7C000000, 0x7E000000, 0x80000000, 0x82000000, 0x84000000, 0x86000000, 0x88000000, 0x8A000000, 0x8C000000, 0x8E000000, 0x90000000, 0x92000000, 0x94000000, 0x96000000, 0x98000000, 0x9A000000,
	};

	uint CLZDecompBase::m_lzx_position_extra_mask[CLZDecompBase::cLZXMaxPositionSlots] =
	{
		0x0, 0x0, 0x0, 0x0, 0x1, 0x1, 0x3, 0x3, 0x7, 0x7, 0xF, 0xF, 0x1F, 0x1F, 0x3F, 0x3F,
		0x7F, 0x7F, 0xFF, 0xFF, 0x1FF, 0x1FF, 0x3FF, 0x3FF, 0x7FF, 0x7FF, 0xFFF, 0xFFF, 0x1FFF, 0x1FFF, 0x3FFF, 0x3FFF,
		0x7FFF, 0x7FFF, 0xFFFF, 0xFFFF, 0x1FFFF, 0x1FFFF, 0x3FFFF, 0x3FFFF, 0x7FFFF, 0x7FFFF, 0xFFFFF, 0xFFFFF, 0x1FFFFF, 0x1FFFFF, 0x3FFFFF, 0x3FFFFF,
		0x7FFFFF, 0x7FFFFF, 0xFFFFFF, 0xFFFFFF, 0x1FFFFFF, 0x1FFFFFF, 0x1FFFFFF, 0x1FFFFFF, 0x1FFFFFF, 0x1FFFFFF, 0x1FFFFFF, 0x1FFFFFF, 0x1FFFFFF, 0x1FFFFFF, 0x1FFFFFF, 0x1FFFFFF,
		0x1FFFFFF, 0x1FFFFFF, 0x1FFFFFF, 0x1FFFFFF, 0x1FFFFFF, 0x1FFFFFF, 0x1FFFFFF, 0x1FFFFFF, 0x1FFFFFF, 0x1FFFFFF, 0x1FFFFFF, 0x1FFFFFF, 0x1FFFFFF, 0x1FFFFFF, 0x1FFFFFF, 0x1FFFFFF,
		0x1FFFFFF, 0x1FFFFFF, 0x1FFFFFF, 0x1FFFFFF, 0x1FFFFFF, 0x1FFFFFF, 0x1FFFFFF, 0x1FFFFFF, 0x1FFFFFF, 0x1FFFFFF, 0x1FFFFFF, 0x1FFFFFF, 0x1FFFFFF, 0x1FFFFFF, 0x1FFFFFF, 0x1FFFFFF,
		0x1FFFFFF, 0x1FFFFFF, 0x1FFFFFF, 0x1FFFFFF, 0x1FFFFFF, 0x1FFFFFF, 0x1FFFFFF, 0x1FFFFFF, 0x1FFFFFF, 0x1FFFFFF, 0x1FFFFFF, 0x1FFFFFF, 0x1FFFFFF, 0x1FFFFFF, 0x1FFFFFF, 0x1FFFFFF,
		0x1FFFFFF, 0x1FFFFFF, 0x1FFFFFF, 0x1FFFFFF, 0x1FFFFFF, 0x1FFFFFF, 0x1FFFFFF, 0x1FFFFFF, 0x1FFFFFF, 0x1FFFFFF, 0x1FFFFFF, 0x1FFFFFF, 0x1FFFFFF, 0x1FFFFFF, 0x1FFFFFF, 0x1FFFFFF
	};

	uint8 CLZDecompBase::m_lzx_position_extra_bits[CLZDecompBase::cLZXMaxPositionSlots] =
	{
		0x0, 0x0, 0x0, 0x0, 0x1, 0x1, 0x2, 0x2, 0x3, 0x3, 0x4, 0x4, 0x5, 0x5, 0x6, 0x6,
		0x7, 0x7, 0x8, 0x8, 0x9, 0x9, 0xA, 0xA, 0xB, 0xB, 0xC, 0xC, 0xD, 0xD, 0xE, 0xE,
		0xF, 0xF, 0x10, 0x10, 0x11, 0x11, 0x12, 0x12, 0x13, 0x13, 0x14, 0x14, 0x15, 0x15, 0x16, 0x16,
		0x17, 0x17, 0x18, 0x18, 0x19, 0x19, 0x19, 0x19, 0x19, 0x19, 0x19, 0x19, 0x19, 0x19, 0x19, 0x19,
		0x19, 0x19, 0x19, 0x19, 0x19, 0x19, 0x19, 0x19, 0x19, 0x19, 0x19, 0x19, 0x19, 0x19, 0x19, 0x19,
		0x19, 0x19, 0x19, 0x19, 0x19, 0x19, 0x19, 0x19, 0x19, 0x19, 0x19, 0x19, 0x19, 0x19, 0x19, 0x19,
		0x19, 0x19, 0x19, 0x19, 0x19, 0x19, 0x19, 0x19, 0x19, 0x19, 0x19, 0x19, 0x19, 0x19, 0x19, 0x19,
		0x19, 0x19, 0x19, 0x19, 0x19, 0x19, 0x19, 0x19, 0x19, 0x19, 0x19, 0x19, 0x19, 0x19, 0x19, 0x19
	};

	static const uint8 g_num_lzx_position_slots[] = { 30, 32, 34, 36, 38, 40, 42, 44, 46, 48, 50, 52, 54, 58, 66 };

   void CLZDecompBase::init_position_slots(uint dict_size_log2)
   {
		LZHAM_ASSERT(dict_size_log2 >= LZHAM_MIN_DICT_SIZE_LOG2);
		LZHAM_ASSERT(dict_size_log2 <= LZHAM_MAX_DICT_SIZE_LOG2_X64);
		LZHAM_ASSERT((sizeof(g_table_update_settings) / sizeof(g_table_update_settings[0])) == LZHAM_FASTEST_TABLE_UPDATE_RATE);

		//for (dict_size_log2 = LZHAM_MIN_DICT_SIZE_LOG2; dict_size_log2 <= LZHAM_MAX_DICT_SIZE_LOG2_X64; dict_size_log2++) {

      m_dict_size_log2 = dict_size_log2;
      m_dict_size = 1U << dict_size_log2;
		m_num_lzx_slots = g_num_lzx_position_slots[dict_size_log2  - LZHAM_MIN_DICT_SIZE_LOG2];

#if 0
		int i, j;
      for (i = 0, j = 0; i < cLZXMaxPositionSlots; i += 2) 
      {
         m_lzx_position_extra_bits[i] = (uint8)j;
         m_lzx_position_extra_bits[i + 1] = (uint8)j; 

         if ((i != 0) && (j < 25))  
            j++; 
      }

      for (i = 0, j = 0; i < cLZXMaxPositionSlots; i++) 
      {
         m_lzx_position_base[i] = j;
         m_lzx_position_extra_mask[i] = (1 << m_lzx_position_extra_bits[i]) - 1;
         j += (1 << m_lzx_position_extra_bits[i]);
      }

		for (uint i = 0; i < cLZXMaxPositionSlots; i++)
		{
			printf("0x%X, ", m_lzx_position_base[i]);
			if ((i & 15) == 15) printf("\n");
		}
#endif

#if 0
      m_num_lzx_slots = 0;         
      
      const uint largest_dist = m_dict_size - 1;
      for (i = 0; i < cLZXMaxPositionSlots; i++)
      {
         if ( (largest_dist >= m_lzx_position_base[i]) &&
              (largest_dist < (m_lzx_position_base[i] + (1 << m_lzx_position_extra_bits[i])) ) )
         {
            m_num_lzx_slots = i + 1;
            break;
         }              
      }
      
      LZHAM_VERIFY(m_num_lzx_slots);
#endif

		//printf("%u, ", m_num_lzx_slots); }
   }
	  
} //namespace lzham