CnC_Renegade/Code/wwbitpack/bitstream.cpp

/*
**	Command & Conquer Renegade(tm)
**	Copyright 2025 Electronic Arts Inc.
**
**	This program is free software: you can redistribute it and/or modify
**	it under the terms of the GNU General Public License as published by
**	the Free Software Foundation, either version 3 of the License, or
**	(at your option) any later version.
**
**	This program is distributed in the hope that it will be useful,
**	but WITHOUT ANY WARRANTY; without even the implied warranty of
**	MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
**	GNU General Public License for more details.
**
**	You should have received a copy of the GNU General Public License
**	along with this program.  If not, see <http://www.gnu.org/licenses/>.
*/

/***********************************************************************************************
 ***              C O N F I D E N T I A L  ---  W E S T W O O D  S T U D I O S               ***
 ***********************************************************************************************
 *                                                                                             *
 *                 Project Name : wwbitpack                                                    *
 *                                                                                             *
 *                     $Archive:: /Commando/Code/wwbitpack/bitstream.cpp                      $*
 *                                                                                             *
 *              Original Author:: Tom Spencer-Smith                                            *
 *                                                                                             *
 *                      $Author:: Bhayes                                                      $*
 *                                                                                             *
 *                     $Modtime:: 2/18/02 10:49p                                              $*
 *                                                                                             *
 *                    $Revision:: 4                                                           $*
 *                                                                                             *
 *---------------------------------------------------------------------------------------------*
 * Functions:                                                                                  *
 * - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - */


#include "bitstream.h"

#include <string.h>	// for strlen
#include <math.h>		// for ceil

#include "wwdebug.h"
#include "mathutil.h"
#include "widestring.h"


//-----------------------------------------------------------------------------
BitStreamClass::BitStreamClass() :
	cBitPacker(),
	UncompressedSizeBytes(0)
{
}

//-----------------------------------------------------------------------------
BitStreamClass& BitStreamClass::operator=(const BitStreamClass& rhs)
{
	//
	// Call operator for base class
	//
	cBitPacker::operator= (rhs);

	UncompressedSizeBytes = rhs.UncompressedSizeBytes;

   return * this;
}

//-----------------------------------------------------------------------------
void BitStreamClass::Add(bool value)
{
	if (cEncoderList::Is_Compression_Enabled()) {
		Add_Bits(value, 1);
	} else {
		Add_Bits(value, BIT_DEPTH(bool));
	}

	UncompressedSizeBytes += BYTE_DEPTH(bool);
}

//-----------------------------------------------------------------------------
bool BitStreamClass::Get(bool & value)
{
	ULONG u_value;
	if (cEncoderList::Is_Compression_Enabled()) {
		Get_Bits(u_value, 1);
	} else {
		Get_Bits(u_value, BIT_DEPTH(bool));
	}

	value = (u_value == 1);
	return value;
}

//-----------------------------------------------------------------------------
void BitStreamClass::Add_Raw_Data(LPCSTR data, USHORT data_size)
{
	WWASSERT(data != NULL);
	WWASSERT(data_size >= 0);

	for (int i = 0; i < data_size; i++) {
		Add(data[i]);
	}
}

//-----------------------------------------------------------------------------
void BitStreamClass::Get_Raw_Data(char * buffer, USHORT buffer_size, USHORT data_size)
{
	WWASSERT(buffer != NULL);
	WWASSERT(data_size >= 0);
   WWASSERT(buffer_size >= data_size);

	for (int i = 0; i < data_size; i++) {
		Get(buffer[i]);
	}
}

//-----------------------------------------------------------------------------
void BitStreamClass::Add_Terminated_String(LPCSTR string, bool permit_empty)
{
	WWASSERT(string != NULL);

	//
	// The terminating null is not transmitted.
	//
	USHORT len = (USHORT) strlen(string);
	if (!permit_empty) {
		WWASSERT(len > 0);
	}

	Add(len);
	for (int i = 0; i < len; i++) {
		Add(string[i]);
	}
}

//-----------------------------------------------------------------------------
void BitStreamClass::Get_Terminated_String(char * buffer, USHORT buffer_size, bool permit_empty)
{
	WWASSERT(buffer != NULL);
	WWASSERT(buffer_size > 0);

	USHORT len;
	Get(len);
	WWASSERT(len < buffer_size);
	if (!permit_empty) {
		WWASSERT(len > 0);
	}

	char temp = '?';
	int i = 0;
	for (i = 0; i < len; i++) {
		Get(temp);
		if (i < buffer_size - 1) {
			buffer[i] = temp;
		}
	}

	// Null-terminate it.
	if (i < buffer_size) {
		buffer[i] = 0;
	} else {
		buffer[buffer_size - 1] = 0;
	}
}


//-----------------------------------------------------------------------------
void BitStreamClass::Add_Wide_Terminated_String(const WCHAR *string, bool permit_empty)
{
	WWASSERT(string != NULL);

	//
	// The terminating null is not transmitted.
	//
	USHORT len = (USHORT)wcslen (string);
	if (!permit_empty) {
		WWASSERT(len > 0 && "Empty string not permitted");
	}

	Add(len);
	for (int i = 0; i < len; i++) {
		Add(string[i]);
	}
}

//-----------------------------------------------------------------------------
void BitStreamClass::Get_Wide_Terminated_String(WCHAR *buffer, USHORT buffer_len, bool permit_empty)
{
	WWASSERT(buffer != NULL);
	WWASSERT(buffer_len > 0);

	USHORT len;
	Get(len);
	WWASSERT(len < buffer_len && "String length exceeds provided buffer");
	if (!permit_empty) {
		WWASSERT(len > 0 && "Empty string not permitted");
	}

	WCHAR temp = L'?';
	int i = 0;
	for (i = 0; i < len; i++) {
		Get(temp);
		if (i < buffer_len - 1) {
			buffer[i] = temp;
		}
	}

	if (i < buffer_len - 1) {
		buffer[i] = 0; // Null-terminate it.
	} else {
		buffer[buffer_len-1] = 0;
	}
}


//-----------------------------------------------------------------------------
UINT BitStreamClass::Get_Compressed_Size_Bytes() const
{
	return (UINT) ceil(Get_Bit_Write_Position() / 8.0f);
}

//-----------------------------------------------------------------------------
UINT BitStreamClass::Get_Compression_Pc() const
{
	UINT c_size = Get_Compressed_Size_Bytes();
	UINT u_size = Get_Uncompressed_Size_Bytes();

	if (cEncoderList::Is_Compression_Enabled()) {
		WWASSERT(c_size <= u_size);
	} else {
		WWASSERT(c_size == u_size);
	}

	WWASSERT(u_size > 0);

	UINT compression_pc = (UINT) cMathUtil::Round(100 * c_size / (float) u_size);
	WWASSERT(compression_pc >= 0 && compression_pc <= 100);

	return compression_pc;
}